1
|
Botelho Meireles de Souza G, Bisinotto Pereira M, Clementino Mourão L, Gonçalves Alonso C, Jegatheesan V, Cardozo-Filho L. Valorization of e-waste via supercritical water technology: An approach for obsolete mobile phones. Chemosphere 2023; 337:139343. [PMID: 37379987 DOI: 10.1016/j.chemosphere.2023.139343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 06/21/2023] [Accepted: 06/24/2023] [Indexed: 06/30/2023]
Abstract
The improper handling of electronic waste has not only severe environmental impacts but also results in the loss of high economic potential. To address this issue, the use of supercritical water (ScW) technology for the eco-friendly processing of waste printed circuit boards (WPCBs) obtained from obsolete mobile phones has been explored in this study. The WPCBs were characterized via MP-AES, WDXRF, TG/DTA, CHNS elemental analysis, SEM and XRD. A L9 Taguchi orthogonal array design was employed to evaluate the impact of four independent variables on the organic degradation rate (ODR) of the system. After optimization, an ODR of 98.4% was achieved at a temperature of 600 °C, a reaction time of 50 min, a flowrate of 7 mL min-1, and the absence of an oxidizing agent. The removal of the organic content from the WPCBs resulted in an increase in the metal concentration, with up to 92.6% of the metal content being efficiently recovered. During the ScW process, the decomposition by-products were continuously removed from the reactor system through the liquid or gaseous outputs. The liquid fraction, which was composed of phenol derivatives, was treated using the same experimental apparatus, achieving a total organic carbon reduction of 99.2% at 600 °C using H2O2 as the oxidizing agent. The gaseous fraction was found to contain hydrogen, methane, CO2, and CO as the major components. Finally, the addition of co-solvents, namely ethanol and glycerol, enhanced the production of combustible gases during the ScW processing of WPCBs.
Collapse
Affiliation(s)
- Guilherme Botelho Meireles de Souza
- Programa de Pós-Graduação Em Engenharia Química, Universidade Estadual de Maringá (UEM), Avenida Colombo, 5790 - Zona 7, Maringá, PR, 87020-900, Brazil; Programa de Pós-Graduação Em Engenharia Química, Universidade Federal de Goiás (UFG), Avenida Esperança, S/n - Chácaras de Recreio Samambaia, Goiânia, GO, 74690-900, Brazil; School of Engineering and Water: Effective Technologies and Tools (WETT) Research Centre, RMIT University, Melbourne, VIC, 3000, Australia.
| | - Mariana Bisinotto Pereira
- Programa de Pós-Graduação Em Engenharia Química, Universidade Estadual de Maringá (UEM), Avenida Colombo, 5790 - Zona 7, Maringá, PR, 87020-900, Brazil.
| | - Lucas Clementino Mourão
- Programa de Pós-Graduação Em Engenharia Química, Universidade Federal de Goiás (UFG), Avenida Esperança, S/n - Chácaras de Recreio Samambaia, Goiânia, GO, 74690-900, Brazil.
| | - Christian Gonçalves Alonso
- Programa de Pós-Graduação Em Engenharia Química, Universidade Federal de Goiás (UFG), Avenida Esperança, S/n - Chácaras de Recreio Samambaia, Goiânia, GO, 74690-900, Brazil.
| | - Veeriah Jegatheesan
- School of Engineering and Water: Effective Technologies and Tools (WETT) Research Centre, RMIT University, Melbourne, VIC, 3000, Australia.
| | - Lucio Cardozo-Filho
- Programa de Pós-Graduação Em Engenharia Química, Universidade Estadual de Maringá (UEM), Avenida Colombo, 5790 - Zona 7, Maringá, PR, 87020-900, Brazil; School of Engineering and Water: Effective Technologies and Tools (WETT) Research Centre, RMIT University, Melbourne, VIC, 3000, Australia; Escola de Engenharia, Universidade Estadual de São Paulo (UNESP), Avenida Professora Isette Corrêa Fontão, 505 - Jardim Das Flores, São João da Boa Vista, SP, 13876-750, Brazil.
| |
Collapse
|
2
|
Ha LT. Scrutinizing the nexus between green innovations and the sustainability of environmental system: novel insights from European database. Environ Sci Pollut Res Int 2023; 30:109087-109109. [PMID: 37759063 DOI: 10.1007/s11356-023-29974-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023]
Abstract
A study is presented in this paper that examines the effect of environmental innovation (EI) on environmental performance (EP). Six measures are used to reflect environmental innovation, including the percentage of enterprises that invest in environmental innovation, the percentage of enterprises implementing environmental innovation activities, the number of ISO 14001 certificates, patents related to environmental innovation, the total R&D personnel and researchers, and the amount of green early-stage investments. The estimation results show that EI positively impacts EP in 21 European countries using different econometric techniques during the 2011-2019 period. By using various econometric techniques (namely a panel-corrected standard errors (PCSE) model, a feasible generalized least square estimates (FGLS) model, and the two-step general method of moment (the two-step GMM), our research demonstrates how environmental innovation impacts on environmental quality. The short- and long-term effects of autoregressive distributed lag (ARDL) methods were also investigated using pooled mean groups (PMGs) to distinguish the short-run and long-run influences of EI. The relationship between EI and EP is explored by demonstrating how EI affects EP short- and long-term and comparing its influence on EP across many component measures of EI: air quality, sanitation, drinking water, heavy metals, waste management, biodiversity, habitat, ecosystem services, water resources, and agriculture. Notably, we find that the influences of EI become more pronounced in a country characterized by a well-developed institutional system. Our findings suggest policy implications to help countries invest in research and development with concerns about environmental damage mitigations more effectively. These findings are critical to suggest a way to help countries pursue ecological sustainability.
Collapse
Affiliation(s)
- Le Thanh Ha
- Faculty of Economics, National Economics University, Hanoi, Vietnam.
| |
Collapse
|
3
|
Seif R, Salem FZ, Allam NK. E-waste recycled materials as efficient catalysts for renewable energy technologies and better environmental sustainability. Environ Dev Sustain 2023:1-36. [PMID: 36691418 PMCID: PMC9848041 DOI: 10.1007/s10668-023-02925-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 01/07/2023] [Indexed: 06/17/2023]
Abstract
Waste from electrical and electronic equipment exponentially increased due to the innovation and the ever-increasing demand for electronic products in our life. The quantities of electronic waste (e-waste) produced are expected to reach 44.4 million metric tons over the next five years. Consequently, the global market for electronics recycling is expected to reach $65.8 billion by 2026. However, electronic waste management in developing countries is not appropriately handled, as only 17.4% has been collected and recycled. The inadequate electronic waste treatment causes significant environmental and health issues and a systematic depletion of natural resources in secondary material recycling and extracting valuable materials. Electronic waste contains numerous valuable materials that can be recovered and reused to create renewable energy technologies to overcome the shortage of raw materials and the adverse effects of using non-renewable energy resources. Several approaches were devoted to mitigate the impact of climate change. The cooperate social responsibilities supported integrating informal collection and recycling agencies into a well-structured management program. Moreover, the emission reductions resulting from recycling and proper management systems significantly impact climate change solutions. This emission reduction will create a channel in carbon market mechanisms by trading the CO2 emission reductions. This review provides an up-to-date overview and discussion of the different categories of electronic waste, the recycling methods, and the use of high recycled value-added (HAV) materials from various e-waste components in green renewable energy technologies.
Collapse
Affiliation(s)
- Rania Seif
- Energy Materials Laboratory, School of Sciences and Engineering, The American University in Cairo, New Cairo, 11835 Egypt
| | - Fatma Zakaria Salem
- Energy Materials Laboratory, School of Sciences and Engineering, The American University in Cairo, New Cairo, 11835 Egypt
| | - Nageh K. Allam
- Energy Materials Laboratory, School of Sciences and Engineering, The American University in Cairo, New Cairo, 11835 Egypt
| |
Collapse
|
4
|
He H, Yang B, Wu D, Gao X, Fei X. Applications of crushing and grinding-based treatments for typical metal-containing solid wastes: Detoxification and resource recovery potentials. Environ Pollut 2022; 314:120034. [PMID: 36030964 DOI: 10.1016/j.envpol.2022.120034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 08/14/2022] [Accepted: 08/20/2022] [Indexed: 06/15/2023]
Abstract
Metal-containing solid wastes can induce serious environmental pollution if managed improperly, but contain considerable resources. The detoxification and resource recoveries of these wastes are of both environmental and economic significances, being indispensable for circular economy. In the past decades, attempts have been made worldwide to treat these wastes. Crushing and grinding-based treatments have been increasingly applied, the operating apparatus and parameters of which depend on the waste type and treatment purpose. Based on the relevant studies, the applications of crushing and grinding on four major types of solid wastes, namely spent lithium-ion batteries (LIBs) cathode, waste printed circuit boards (WPCBs), incineration bottom ash (IBA), and incineration fly ash (IFA) are here systematically reviewed. These types of solid wastes are generated in increasing amounts, and have the potentials to release various organic and inorganic pollutants. Despite of the widely different texture, composition, and other physicochemical properties of the solid wastes, crushing and grinding have been demonstrated to be universally applicable. For each of the four wastes, the technical route that involving crushing and grinding is described with the advantages highlighted. The crushing and grinding serve either mainstream or auxiliary role in the processing of the solid wastes. This review summarizes and highlights the developments and future directions of crushing and grinding-based treatments.
Collapse
Affiliation(s)
- Hongping He
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China; School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore
| | - Bo Yang
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China
| | - Deli Wu
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science & Engineering, Tongji University, Shanghai, 200092, PR China; Shanghai Institute of Pollution Control Ecological Security, Shanghai, 200092, PR China
| | - Xiaofeng Gao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
| | - Xunchang Fei
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore; Residues and Resource Reclamation Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, 637141, Singapore.
| |
Collapse
|
5
|
Torrubia J, Valero A, Valero A. Thermodynamic Rarity Assessment of Mobile Phone PCBs: A Physical Criticality Indicator in Times of Shortage. Entropy (Basel) 2022; 24:100. [PMID: 35052126 DOI: 10.3390/e24010100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/20/2021] [Accepted: 01/04/2022] [Indexed: 12/10/2022]
Abstract
Rising prices in energy, raw materials, and shortages of critical raw materials (CRMs) for renewable energies or electric vehicles are jeopardizing the transition to a low-carbon economy. Therefore, managing scarce resources must be a priority for governments. To that end, appropriate indicators that can identify the criticality of raw materials and products is key. Thermodynamic rarity (TR) is an exergy-based indicator that measures the scarcity of elements in the earth’s crust and the energy intensity to extract and refine them. This paper uses TR to study 70 Mobile Phone (MP) Printed Circuit Boards (PCBs) samples. Results show that an average MP PCB has a TR of 88 MJ per unit, indicating their intensive use of valuable materials. Every year the embedded TR increases by 36,250 GWh worldwide -similar to the electricity consumed by Denmark in 2019- due to annual production of MP. Pd, Ta and Au embedded in MP PCBs worldwide between 2007 and 2021 contribute to 90% of the overall TR, which account for 75, 600 and 250 tones, respectively, and increasing by 11% annually. This, coupled with the short lifespan of MP, makes PCBs an important potential source of secondary resources.
Collapse
|
6
|
Thacker SC, Nayak NS, Tipre DR, Dave SR. Impact of Pulverization, Pretreatment and pH Regulation on Microbial Extraction of Metals from Waste Mobile Phone Printed Circuit Boards. APPL BIOCHEM MICRO+ 2021. [DOI: 10.1134/s0003683821050173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
7
|
Das SK, Ellamparuthy G, Kundu T, Ghosh MK, Angadi SI. Critical analysis of metallic and non-metallic fractions in the flotation of waste printed circuit boards. POWDER TECHNOL 2021. [DOI: 10.1016/j.powtec.2021.05.061] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
8
|
Ellamparuthy G, Angadi SI, Rao DS, Ghosh MK, Basu S. Separation and characterization studies of end-of-life mobile printed circuit boards. Particulate Science and Technology 2021. [DOI: 10.1080/02726351.2020.1756547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- G. Ellamparuthy
- AcSIR-Academy of Scientific and Innovative Research, Ghaziabad, India
- CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, India
| | - S. I. Angadi
- AcSIR-Academy of Scientific and Innovative Research, Ghaziabad, India
- CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, India
| | - D. S. Rao
- AcSIR-Academy of Scientific and Innovative Research, Ghaziabad, India
- CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, India
| | - M. K. Ghosh
- AcSIR-Academy of Scientific and Innovative Research, Ghaziabad, India
- CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, India
| | - S. Basu
- AcSIR-Academy of Scientific and Innovative Research, Ghaziabad, India
- CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, India
| |
Collapse
|
9
|
Annamalai M, Gurumurthy K. Characterization of end-of-life mobile phone printed circuit boards for its elemental composition and beneficiation analysis. J Air Waste Manag Assoc 2021; 71:315-327. [PMID: 32841086 DOI: 10.1080/10962247.2020.1813836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 08/03/2020] [Accepted: 08/07/2020] [Indexed: 06/11/2023]
Abstract
Globally, waste electrical and electronic equipment is one of the fastest-growing waste sectors. Mobile phones constitute the major portion of the telecommunication e-waste category. Over the years, waste mobile phones were considered as a potential source of secondary metals. This study aims to determine the physical and chemical composition of the discarded mobile phones and to evaluate its recovery potential. The printed circuit boards from the discarded (waste) mobile phones (MPCB) were collected and samples of different sizes 3 × 3 cm, 2 mm, 1 mm, 500 µm, and 150 µm were obtained after milling and sieving. Elemental composition revealed the presence of base metals, Cu, Zn, Fe, Ni, and Pb, in higher quantities with a significant amount of precious metals Au and Ag. Amount of base metals present in different MPCB size fractions was found in the order 3 × 3 cm > 2 mm > 1 mm > 500 µm >150 µm. The amount of precious metals like Ag and Au was found to be higher in large-sized MPCB fractions. FTIR studies declared the presence of polymers like ABS, PC, and HIPs in MPCB samples. TCLP tests for toxic metals revealed that MPCBs contained high concentrations of cadmium, lead, and mercury highlighting their hazardous potential. The ultimate analysis revealed that NMF has a GCV of 12.34 MJ/kg and a volatile content of 42.25%, which can be a potential source of energy that can be recovered through the gasification or pyrolysis process. Overall, the comprehensive characterization of waste MPCBs will systematically provide a better understanding of e-waste recycling processes for beneficiation purpose and sustainable resource utilization.Implications: A comprehensive characterization of waste mobile phone printed circuit boards for its elemental composition was performed. Mechanical treatment steps before MPCBs processing increased the exposure of metals resulting in a higher concentration of metals in acid-digested samples. The elemental analysis of MPCBs revealed that MPCBs possessed significant quantities of base and precious metals. The amount of precious metals like Ag and Au was also found in higher ranges in large-sized MPCB fractions, which elucidated fact to be considered in the pre-treatment process for metal recoveries. The high content of base and precious metals in waste mobile phones displayed their economic potential in the market. This new source may compensate for the escalating global demand for gold and silver. Results from the study indicated that MPCBs can serve as an excellent secondary source for various metals and as an efficient alternative fuel.
Collapse
Affiliation(s)
- Mohan Annamalai
- School of Biosciences and Technology, Vellore Institute of Technology, Vellore, India
| | - Kalaichelvan Gurumurthy
- VIT School of Agriculture Innovations and Advanced Learning, Vellore Institute of Technology, Vellore, India
| |
Collapse
|
10
|
Das D, Mukherjee S, Chaudhuri MG. Studies on leaching characteristics of electronic waste for metal recovery using inorganic and organic acids and base. Waste Manag Res 2021; 39:242-249. [PMID: 32564701 DOI: 10.1177/0734242x20931929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this paper, we report leaching of precious and scattered metals such as gold (Au), copper (Cu), nickel (Ni), zinc (Zn), iron (Fe), and lead (Pb) from printed circuit boards of scrap mobile phones by hydrometallurgical process using inorganic acid, organic acid and base. The amount of metals leached by different leachants are quantified using atomic absorption spectroscopy. Among various inorganic acids, aqua regia (mixture of nitric acid (HNO3) and hydrochloric acid) is found to be the strongest leachant for most of the metals such as Zn (2.04 wt %), Fe (17.90 wt %), Ni (0.66 wt %), Pb (5.86 wt %) and Au (0.04 wt %). The basic leachant, ammonium thiosulphate is found to be very effective in leaching of Au (0.03125 wt %). The dissolution of Cu in HNO3 gives the highest amount of Cu in the solvent, that is, ∼ 7.52 wt %. The metallic phases present in the electronic waste before and after leaching are identified by X-ray diffraction analysis. The microscopic structure has been studied using a scanning electron microscope which depicts erosion of the structure after leaching.
Collapse
Affiliation(s)
- Debarati Das
- School of Materials Science & Nanotechnology, Jadavpur University, India
| | | | | |
Collapse
|
11
|
Mota-panizio R, Hermoso-orzáez MJ, Carmo-calado L, Campos VAFD, Silveira JL, Gonçalves MM, Brito P. Energy Recovery via Thermal Gasification from Waste Insulation Electrical Cables (WIEC). Applied Sciences 2020; 10:8253. [DOI: 10.3390/app10228253] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The recovery of noble metals from electrical wires and cables results in waste materials such as polyvinyl chloride (PVC) and polyethylene (PE), that is, waste insulation electrical cables (WIEC), which have been processed by gasification for energy recovery. This study focused on the effect of blending the ratio of WIEC on the gasification feedstock composition and the lower heating value (LHV) of produced syngas, through controlled tests and tests under different loads on the generator. The controlled gasification experiments were carried out at blending ratios between pine biomass and WIEC of 90:10, 80:20, and 70:30 and with pine biomass only (100%). For the loads gasification, the experiments were carried out at a blending ratio of 80:20. The controlled experimental results presented that the highest hydrogen content, approximated 17.7 vol.%, was observed at a blending ratio of 70:30 between pine biomass and WIEC and the highest LHV of syngas was observed at a blending ratio of 90:10, with 5.7 MJ/Nm3. For the load gasification experiments, the results showed that the highest hydrogen content was obtained with a load of 15 kW in the generator, approximately 18.48 vol.% of hydrogen content, and the highest LHV of synthesis gas was observed during the 5 kW test, with 5.22 MJ/Nm3. Overall, the new processing of waste insulation electrical cables using a downdraft gasification reactor demonstrates great promise for high quality syngas production.
Collapse
|
12
|
Remeteiová D, Ružičková S, Mičková V, Laubertová M, Slezáková R. Evaluation of US EPA Method 3052 Microwave Acid Digestion for Quantification of Majority Metals in Waste Printed Circuit Boards. Metals 2020; 10:1511. [DOI: 10.3390/met10111511] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Metal content determination is one of the critical aspects of preparing electronic waste for metal recycling. In spite of the fact that end-of-life printed circuit boards are considered to be a secondary resource reservoir, no standard procedure exists for determining the total metal content in this heterogeneous multicomponent material containing plastics, metals, alloys and ceramics. We investigated the utilization of United States Environmental Protection Agency (US EPA) microwave acid digestion (Method 3052) and various modifications of this procedure for effective releasing of Cu, Fe, Ni, Pb and Zn from waste printed circuit boards (WPCBs) from mobile phones. The maximum contents of Cu (22.6 wt.%), Fe (5.0 wt.%), Ni (2.0 wt.%) and Zn (2.6 wt.%) were obtained using the standard (unmodified) US EPA 3052 digestion procedure, but the total digestion of PCB material was not achieved. The solid residue material after digestion by means of the US EPA 3052 method consisted predominantly of oxides (Ca, Mg and Al) and fluorides (Ca and Mg), and some particles contained minor amounts of Fe and Cu.
Collapse
|
13
|
Hermoso-orzáez MJ, Mota-panizio R, Carmo-calado L, Brito P. Thermochemical and Economic Analysis for Energy Recovery by the Gasification of WEEE Plastic Waste from the Disassembly of Large-Scale Outdoor Obsolete Luminaires by LEDs in the Alto Alentejo Region (Portugal). Applied Sciences 2020; 10:4601. [DOI: 10.3390/app10134601] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The recovery of urban waste is a social demand and a measure of the energy-environmental sustainability of cities and regions. In particular, waste of electrical origin, waste of electrical and electronic materials (WEEE) can be recovered with great success. The plastic fraction of these wastes allows their gasification mixed with biomass, and the results allow for producing syngas with a higher energy potential. This work allows for obtaining energy from the recovery of obsolete materials through thermochemical conversion processes of the plastic waste from the disassembly of the luminaires by mixing the said plastic waste in different proportions with the biomass of crop residues (olive). The gasification tests of these mixtures were carried out in a downstream fixed-bed drown daft reactor, at temperatures of approximately 800 °C. The results demonstrate the applied technical and economic feasibility of the technology by thermal gasification, for the production of LHV (Low Heating Value) syngas with highest power energy (more than 5 MJ/m3) produced in mixtures of up to 20% of plastic waste. This study was complemented with the economic-financial analysis. This research can be used as a case study for the energy recovery through gasification processes of plastic waste from luminaires (WEEE), mixed with agricultural biomass that is planned to be carried out on a large scale in the Alentejo (Portugal), as a solution applied in circular economy strategies.
Collapse
|
14
|
Singh N, Duan H, Ogunseitan OA, Li J, Tang Y. Toxicity trends in E-Waste: A comparative analysis of metals in discarded mobile phones. J Hazard Mater 2019; 380:120898. [PMID: 31330384 DOI: 10.1016/j.jhazmat.2019.120898] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 06/24/2019] [Accepted: 07/13/2019] [Indexed: 06/10/2023]
Abstract
Mobile phones and various electronic products contribute to the world's fastest-growing category of hazardous waste with international repercussions. We investigated the trends in potential human health impacts and ecotoxicity of waste mobile phones through quantitative life cycle impact assessment (LCIA) methods and regulatory total threshold limit concentrations. A market-dominant sample of waste basic phones and smartphones manufactured between 2001 and 2015, were analyzed for toxicity trends based on 19 chemicals. The results of the LCIA (using USEtox model) show an increase in the relative mass of toxic materials over the 15-year period. We found no significant changes in the use of toxic components in basic phones, whereas smartphones contained a statistically significant increase in the content of toxic materials from 2006 to 2015. Nickel contributed the largest risk for carcinogens in mobile phones, but the contributions of lead and beryllium were also notable. Silver, zinc and copper contents were associated with non-cancer health risks. Copper components at 45,818-77,938 PAF m3/kg dominated ecotoxicity risks in mobile phones. Overall, these results highlight the increasing importance of monitoring trends in materials use for electronic product manufacturing and electronic-waste management processes that should prevent human and environmental exposures to toxic components.
Collapse
Affiliation(s)
- Narendra Singh
- School of Civil Engineering, Shenzhen University, Shenzhen, 518060, China; School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China.
| | - Huabo Duan
- School of Civil Engineering, Shenzhen University, Shenzhen, 518060, China.
| | - Oladele A Ogunseitan
- Department of Population Health & Disease Prevention, Program in Public Health, University of California, Irvine, CA, 92697, USA
| | - Jinhui Li
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of & Environment, Tsinghua University, Beijing, 100084, China
| | - Yuanyuan Tang
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| |
Collapse
|
15
|
Fontana D, Pietrantonio M, Pucciarmati S, Rao C, Forte F. A comprehensive characterization of End-of-Life mobile phones for secondary material resources identification. Waste Manag 2019; 99:22-30. [PMID: 31470263 DOI: 10.1016/j.wasman.2019.08.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 08/01/2019] [Accepted: 08/09/2019] [Indexed: 06/10/2023]
Abstract
In this paper a full recognition of the different materials and valuable metals constituting mobile phones was performed. To this aim, a sample of 20 end-of-life devices has been dismantled and quantitative and qualitative chemical composition of the individual components was determined. From dismantling operations, it was found that plastics, metals, electronic components, batteries and displays account for 33%, 11%, 23%, 24% and 9% respectively, as a weighted average. Plastic parts of each item were analyzed by spectroscopy and then classified according to the plastic polymer type; it was found that polymeric components of mobile phones were made of five polymers: acrylonitrile-butadienestyrene, polycarbonate, polyurethane, polymethylmethacrylate and silicone. Electronic parts were leached by a twofold aqua regia treatment and the metal composition was determined: 15 elements were identified with concentration >0.2%. On the basis of these results, some considerations about the recycling context of end-of-life mobile phones were performed.
Collapse
Affiliation(s)
- Danilo Fontana
- ENEA, Italian National Agency for New Technologies, Energy, Sustainable Economic Development, Via Anguillarese 301, 00123 Rome, Italy.
| | - Massimiliana Pietrantonio
- ENEA, Italian National Agency for New Technologies, Energy, Sustainable Economic Development, Via Anguillarese 301, 00123 Rome, Italy
| | - Stefano Pucciarmati
- ENEA, Italian National Agency for New Technologies, Energy, Sustainable Economic Development, Via Anguillarese 301, 00123 Rome, Italy
| | - Concetta Rao
- ENEA, Italian National Agency for New Technologies, Energy, Sustainable Economic Development, Via Anguillarese 301, 00123 Rome, Italy
| | - Federica Forte
- ENEA, Italian National Agency for New Technologies, Energy, Sustainable Economic Development, Via Anguillarese 301, 00123 Rome, Italy
| |
Collapse
|
16
|
Utimura SK, Arevalo SJ, Rosario CGA, Aguilar MQ, Tenório JAS, Espinosa DCR. Bioleaching of metal from waste stream using a native strain of Acidithiobacillusisolated from a coal mine drainage. CAN J CHEM ENG 2019. [DOI: 10.1002/cjce.23519] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Solange Kazue Utimura
- USP, Department of Chemical Engineering Rua do Lago 250 ‐ Cep 05508‐080 São Paulo Brazil
| | | | | | | | | | | |
Collapse
|
17
|
Korf N, Løvik AN, Figi R, Schreiner C, Kuntz C, Mählitz PM, Rösslein M, Wäger P, Rotter VS. Multi-element chemical analysis of printed circuit boards - challenges and pitfalls. Waste Manag 2019; 92:124-136. [PMID: 31160021 DOI: 10.1016/j.wasman.2019.04.061] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 04/24/2019] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
Printed circuit boards (PCB) are an essential component of electrical and electronic equipment (EEE) and account for roughly 5% of the mass of EEE. Knowledge about the chemical composition of PCB is crucial to enable an enhanced recycling, especially for elements considered critical regarding their economic importance and supply risk (e.g. precious metals or specialty metals such as tantalum, germanium, gallium). No standard reference methods exist for determining the chemical composition of PCB. Previously published element mass fractions cover a wide range and were produced with numerous methods for sample preparation, digestion, and measurement. This impedes comparability of PCB composition from different studies. To investigate sample- and element-specific effects of applied methods a PCB sample from desktop PC was analysed in two separate labs. One lab applied sample- and element-specific validated methods (aqua regia, HF, H2SO4 blend; ICP-OES, QQQ-ICP-MS), providing reference values, the other applied routine in-house methods (aqua regia; ICP-OES, ICP-MS) to assess the validity of in-house methods for chemical analysis of PCB. A t-test was used to identify elements depicting significant differences between validated and in-house methods. For base metals, in-house methods led to comparable results. For precious, specialty, and hazardous metals as well as REE investigated in this study, significant differences were detected. With respect to all results for in-house methods in this study, the combination of aqua regia and ICP-OES led to less significant differences than aqua regia and ICP-MS. The results show that sample- and element-specific quality assurance is crucial to prevent analytical bias.
Collapse
Affiliation(s)
- Nathalie Korf
- Chair of Circular Economy and Recycling Technology at Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany.
| | - Amund N Løvik
- Technology and Society Laboratory at Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Renato Figi
- Advanced Analytical Technologies at Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Claudia Schreiner
- Advanced Analytical Technologies at Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Claudia Kuntz
- Chair of Circular Economy and Recycling Technology at Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Paul Martin Mählitz
- Chair of Circular Economy and Recycling Technology at Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Matthias Rösslein
- Particles-Biology Interactions Laboratory at Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Patrick Wäger
- Technology and Society Laboratory at Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Vera Susanne Rotter
- Chair of Circular Economy and Recycling Technology at Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| |
Collapse
|
18
|
Abstract
At the end of 2017 roughly 1.8% of the worldwide electricity came from solar photovoltaics (PV), which is foreseen to have a key role in all major future energy scenarios with an installed capacity around 5 TW by 2050. Despite silicon solar cells currently rule the PV market, the extremely more versatile thin film-based devices (mainly Cu(In,Ga)Se2 and CdTe ones) have almost matched them in performance and present room for improvement. The low availability of some elements in the present commercially available PV technologies and the recent strong fall of silicon module price below 1 $/Wp focused the attention of the scientific community on cheap earth-abundant materials. In this framework, thin film solar cells based on Cu2ZnSnS4 (CZTS) and the related sulfur selenium alloy Cu2ZnSn(S,Se)4 (CZTSSe) were strongly investigated in the last 10 years. More recently, chalcogenide PV absorbers potentially able to face TW range applications better than CZTS and CZTSSe due to the higher abundance of their constituting elements are getting considerable attention. They are based on both MY2 (where M = Fe, Cu, Sn and Y = S and/or Se) and Cu2XSnY4 (where X = Fe, Mn, Ni, Ba, Co, Cd and Y = S and/or Se) chalcogenides. In this work, an extensive review of emerging earth-abundant thin film solar cells based on both MY2 and Cu2XSnY4 species is given, along with some considerations on the abundance and annual production of their constituting elements.
Collapse
Affiliation(s)
| | | | - Simona Binetti
- Department of Materials Science and MIBSOLAR Center, University of Milano-Bicocca, Milan, Italy
| |
Collapse
|
19
|
Cesaro A, Belgiorno V, Gorrasi G, Viscusi G, Vaccari M, Vinti G, Jandric A, Dias MI, Hursthouse A, Salhofer S. A relative risk assessment of the open burning of WEEE. Environ Sci Pollut Res Int 2019; 26:11042-11052. [PMID: 30793245 PMCID: PMC6469622 DOI: 10.1007/s11356-019-04282-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 01/16/2019] [Indexed: 05/11/2023]
Abstract
Waste electric and electronic equipment (WEEE) represents a potential secondary source of valuable materials, whose recovery is a growing business activity worldwide. In low-income countries, recycling is carried out under poorly controlled conditions resulting in severe environmental pollution. High concentrations of both metallic and organic pollutants have been confirmed in air, soil, water, and sediments in countries with informal recycling areas. The release of these contaminants into the environment presents a risk to the health of the exposed population that has been widely acknowledged but still needs to be quantified. The aim of this work was to evaluate the relative risk from inhalation associated with the open burning of different kinds of WEEE. The shrinking core model was applied to estimate the concentration of the metals which would be released into the environment during the incineration of different types of WEEE. In addition, the potential generation of dioxins during the same informal practice was estimated, based on the plastic content of the WEEE. The results provided for the first time a comparative analysis of the risk posed from the open burning of WEEE components, proposing a methodology to address the absolute risk assessment to workers from the informal recycling of WEEE.
Collapse
Affiliation(s)
- Alessandra Cesaro
- Sanitary Environmental Engineering Division (SEED), Department of Civil Engineering, University of Salerno, via Giovanni Paolo II, 84084, Fisciano, SA, Italy.
| | - Vincenzo Belgiorno
- Sanitary Environmental Engineering Division (SEED), Department of Civil Engineering, University of Salerno, via Giovanni Paolo II, 84084, Fisciano, SA, Italy
| | - Giuliana Gorrasi
- Department of Industrial Engineering, University of Salerno, via Giovanni Paolo II, 84084, Fisciano, SA, Italy
| | - Gianluca Viscusi
- Department of Industrial Engineering, University of Salerno, via Giovanni Paolo II, 84084, Fisciano, SA, Italy
| | - Mentore Vaccari
- Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, via Branze 43, 25123, Brescia, Italy
| | - Giovanni Vinti
- Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, via Branze 43, 25123, Brescia, Italy
| | - Aleksander Jandric
- Waste Management Institute, BOKU University, Muthgasse 107, 1190, Vienna, Austria
| | - Maria Isabel Dias
- Centro de Ciências e Tecnologias Nucleares - C2TN, Campus Tecnológico e Nuclear, Polo de Loures, Instituto Superior Técnico, Estrada Nacional 10, km 139,7, Bobadela, 2696-066, Loures, Portugal
| | - Andrew Hursthouse
- University of the West of Scotland Paisley Campus, Paisley, PA1 2BE, UK
| | - Stefan Salhofer
- Waste Management Institute, BOKU University, Muthgasse 107, 1190, Vienna, Austria
| |
Collapse
|
20
|
Liu W, Ford P, Uvegi H, Margarido F, Santos E, Ferrão P, Olivetti E. Economics of materials in mobile phone preprocessing, focus on non-printed circuit board materials. Waste Manag 2019; 87:78-85. [PMID: 31109581 DOI: 10.1016/j.wasman.2019.01.044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 12/24/2018] [Accepted: 01/30/2019] [Indexed: 05/26/2023]
Abstract
Incomplete recovery of materials in mobile phones results in a significant economic loss. Many studies have focused on improving the situation by characterizing metals within printed circuit boards (PCBs) to identify where losses occur. Our work focuses on the evolving composition of mobile phones and particularly the flow of materials located within components outside of PCBs. In this study we quantify the appreciable economic potential of non-PCB derived metals and provide suggestions for optimization of different preprocessing steps to recover these materials. These opportunities can be categorized as recovering both high value and high volume materials. We therefore recommend that preprocessors pay special attention to precious metals in fine shredding and develop strategies for plastics recycling based on our demand and supply forecasts of postconsumer plastics in phones. We have performed this work based on a case study of Portugal.
Collapse
Affiliation(s)
- Weitong Liu
- Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; MIT Portugal Program, Portugal
| | - Patrick Ford
- Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; MIT Portugal Program, Portugal
| | - Hugo Uvegi
- Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Fernanda Margarido
- Department of Mechanical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal; MIT Portugal Program, Portugal
| | - Eduardo Santos
- 3Drivers - Engenharia, Inovação e Ambiente, Lda, Lisbon, Portugal; MIT Portugal Program, Portugal
| | - Paulo Ferrão
- Department of Mechanical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal; MIT Portugal Program, Portugal
| | - Elsa Olivetti
- Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; MIT Portugal Program, Portugal
| |
Collapse
|
21
|
Sahan M, Kucuker MA, Demirel B, Kuchta K, Hursthouse A. Determination of Metal Content of Waste Mobile Phones and Estimation of Their Recovery Potential in Turkey. Int J Environ Res Public Health 2019; 16:ijerph16050887. [PMID: 30862075 PMCID: PMC6427248 DOI: 10.3390/ijerph16050887] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 02/23/2019] [Accepted: 02/27/2019] [Indexed: 01/07/2023]
Abstract
Waste mobile phones constitute one of the fastest growing Waste Electrical and Electronic Equipment (WEEE) types all over the world due to technological innovations and shortening of their life span. They contain a complex mix of various materials, such as basic metals, precious metals and rare earth elements and represent an important secondary raw metal source. The main objectives of this study were to characterize the metal concentration of waste mobile phones by optimizing the inductively coupled plasma optical emission spectrometer (ICP-OES) operation parameters and estimate the metal recovery potential of waste mobile phones in Turkey. Therefore, selected mobile phone samples collected from a recycling center in Turkey were analyzed to determine their metal concentrations. Then, the theoretical recovery potentials of precious and rare earth metals from waste mobile phones were estimated for Turkey. The analytical methods optimized in this study can help further research activities to obtain comprehensive data for determination of the critical metals (precious metals and rare earth elements) in WEEE samples so that proper recycling and recovery strategies can be selected and implemented.
Collapse
Affiliation(s)
- Merve Sahan
- Institute of Environmental Sciences, Bogazici University, Bebek, Istanbul 3432, Turkey.
| | - Mehmet Ali Kucuker
- Institute of Environmental Technology and Energy Economics, Waste Resources Management, TUHH-Hamburg University of Technology, Harburger Schloßstr. 36, 21079 Hamburg, Germany.
- Department of Environmental Engineering, Engineering Faculty, Terzioğlu Campus, Çanakkale Onsekiz Mart University, 17020 Çanakkale, Turkey.
| | - Burak Demirel
- Institute of Environmental Sciences, Bogazici University, Bebek, Istanbul 3432, Turkey.
| | - Kerstin Kuchta
- Institute of Environmental Technology and Energy Economics, Waste Resources Management, TUHH-Hamburg University of Technology, Harburger Schloßstr. 36, 21079 Hamburg, Germany.
| | - Andrew Hursthouse
- Computing Engineering & Physical Sciences, University of the West of Scotland, Paisley PA1 2BE, UK.
| |
Collapse
|
22
|
Işıldar A, van Hullebusch ED, Lenz M, Du Laing G, Marra A, Cesaro A, Panda S, Akcil A, Kucuker MA, Kuchta K. Biotechnological strategies for the recovery of valuable and critical raw materials from waste electrical and electronic equipment (WEEE) - A review. J Hazard Mater 2019; 362:467-481. [PMID: 30268020 DOI: 10.1016/j.jhazmat.2018.08.050] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 08/14/2018] [Accepted: 08/16/2018] [Indexed: 05/05/2023]
Abstract
Critical raw materials (CRMs) are essential in the development of novel high-tech applications. They are essential in sustainable materials and green technologies, including renewable energy, emissionfree electric vehicles and energy-efficient lighting. However, the sustainable supply of CRMs is a major concern. Recycling end-of-life devices is an integral element of the CRMs supply policy of many countries. Waste electrical and electronic equipment (WEEE) is an important secondary source of CRMs. Currently, pyrometallurgical processes are used to recycle metals from WEEE. These processes are deemed imperfect, energy-intensive and non-selective towards CRMs. Biotechnologies are a promising alternative to the current industrial best available technologies (BAT). In this review, we present the current frontiers in CRMs recovery from WEEE using biotechnology, the biochemical fundamentals of these bio-based technologies and discuss recent research and development (R&D) activities. These technologies encompass biologically induced leaching (bioleaching) from various matrices,biomass-induced sorption (biosorption), and bioelectrochemical systems (BES).
Collapse
Affiliation(s)
- Arda Işıldar
- IHE Delft Institute for Water Education, Delft, The Netherlands; Université Paris-Est, Laboratoire Geomatériaux et Environnement (LGE), EA 4508, UPEM, 77454 Marne-la-Vallée, France.
| | - Eric D van Hullebusch
- IHE Delft Institute for Water Education, Delft, The Netherlands; Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Universitè Paris Diderot, UMR 7154, CNRS, F-75005 Paris, France
| | - Markus Lenz
- Fachhochschule Nordwestschweiz, University of Applied Sciences and Arts Northwestern Switzerland, Brugg, Switzerland; Sub-Department of Environmental Technology, Wageningen University, 6700 AA Wageningen, The Netherlands
| | - Gijs Du Laing
- Department of Applied Analytical and Physical Chemistry, Ghent University, Belgium
| | - Alessandra Marra
- Sanitary Environmental Engineering Division (SEED), Department of Civil Engineering, University of Salerno, Italy
| | - Alessandra Cesaro
- Sanitary Environmental Engineering Division (SEED), Department of Civil Engineering, University of Salerno, Italy
| | - Sandeep Panda
- Mineral-Metal Recovery and Recycling Research Group, Mineral Processing Division, Department of Mining Engineering, Suleyman Demirel University, TR32260 Isparta, Turkey
| | - Ata Akcil
- Mineral-Metal Recovery and Recycling Research Group, Mineral Processing Division, Department of Mining Engineering, Suleyman Demirel University, TR32260 Isparta, Turkey
| | - Mehmet Ali Kucuker
- Hamburg University of Technology (TUHH), Institute of Environmental Technology and Energy Economics, Waste Resources Management, Harburger Schloßstr. 36, 21079 Hamburg, Germany
| | - Kerstin Kuchta
- Hamburg University of Technology (TUHH), Institute of Environmental Technology and Energy Economics, Waste Resources Management, Harburger Schloßstr. 36, 21079 Hamburg, Germany
| |
Collapse
|
23
|
Ilankoon IMSK, Ghorbani Y, Chong MN, Herath G, Moyo T, Petersen J. E-waste in the international context - A review of trade flows, regulations, hazards, waste management strategies and technologies for value recovery. Waste Manag 2018; 82:258-275. [PMID: 30509588 DOI: 10.1016/j.wasman.2018.10.018] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 10/10/2018] [Accepted: 10/11/2018] [Indexed: 05/07/2023]
Abstract
E-waste, or waste generated from electrical and electronic equipment, is considered as one of the fastest-growing waste categories, growing at a rate of 3-5% per year in the world. In 2016, 44.7 million tonnes of e-waste were generated in the world, which is equivalent to 6.1 kg for each person. E-waste is classified as a hazardous waste, but unlike other categories, e-waste also has significant potential for value recovery. As a result it is traded significantly between the developed and developing world, both as waste for disposal and as a resource for metal recovery. Only 20% of global e-waste in 2016 was properly recycled or disposed of, with the fate of the remaining 80% undocumented - likely to be dumped, traded or recycled under inferior conditions. This review paper provides an overview of the global e-waste resource and identifies the major challenges in the sector in terms of generation, global trade and waste management strategies. It lists the specific hazards associated with this type of waste that need to be taken into account in its management and includes a detailed overview of technologies employed or proposed for the recovery of value from e-waste. On the basis of this overview the paper identifies future directions for effective e-waste processing towards sustainable waste/resource management. It becomes clear that there is a strong divide between developed and developing countries with regard to this sector. While value recovery is practiced in centralised facilities employing advanced technologies in a highly regulated industrial environment in the developed world, in the developing world such recovery is practiced in a largely unregulated artisanal industry employing simplistic, labour intensive and environmentally hazardous approaches. Thus value is generated safely in the hi-tech environment of the developed world, whereas environmental burdens associated with exported waste and residual waste from simplistic processing remain largely in developing countries. It is argued that given the breadth of available technologies, a more systematic evaluation of the entire e-waste value chain needs to be conducted with a view to establishing integrated management of this resource (in terms of well-regulated value recovery and final residue disposal) at the appropriately local rather than global scale.
Collapse
Affiliation(s)
- I M S K Ilankoon
- Discipline of Chemical Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia; Global Asia in the 21st Century (GA21) Multidisciplinary Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia.
| | - Yousef Ghorbani
- Department of Civil, Environmental & Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden.
| | - Meng Nan Chong
- Discipline of Chemical Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia; Global Asia in the 21st Century (GA21) Multidisciplinary Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia; Sustainable Water Alliance, Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia
| | - Gamini Herath
- Global Asia in the 21st Century (GA21) Multidisciplinary Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia; School of Business, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia
| | - Thandazile Moyo
- Department of Chemical Engineering, University of Cape Town, Rondebosch, South Africa
| | - Jochen Petersen
- Department of Chemical Engineering, University of Cape Town, Rondebosch, South Africa
| |
Collapse
|
24
|
Pita F, Castilho A. Separation of Copper from Electric Cable Waste Based on Mineral Processing Methods: A Case Study. Minerals 2018; 8:517. [DOI: 10.3390/min8110517] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Recycling of electrical cable waste requires a separation between the metal and the insulating material. The objective of this work was to separate the copper from the plastic in electrical cable waste previously ground below 2 mm, using jigging, shaking table and froth flotation techniques. The effect of particle size was also analysed. Jigging and shaking table proved to be effective in the separation of copper from plastics. The result was a copper concentrate with a copper grade of about 97% by both methods and a copper recovery of about 97%. Jigging separation had similar separation efficiencies in the seven-sized fractions, but in shaking table, the separation efficiency improved with an increase in particles size. The separation achieved by froth flotation had lower efficiencies (85%), because plastics are naturally hydrophobic and copper presents some hydrophobic behaviour. In this technique, the addition of depressant agents was mandatory for the depression of copper, even at low concentrations. The best results were obtained with concentrations of 10−1 mg/L of sodium sulfide (407410 Sigma-Aldrich, Sigma-Aldrich Corporation, St. Louis, MO, USA) and meso-2,3-Dimercaptosuccinic acid (D7881 Sigma-Aldrich).
Collapse
|
25
|
Kasper AC, Veit HM. GOLD RECOVERY FROM PRINTED CIRCUIT BOARDS OF MOBILE PHONES SCRAPS USING A LEACHING SOLUTION ALTERNATIVE TO CYANIDE. Braz J Chem Eng 2018. [DOI: 10.1590/0104-6632.20180353s20170291] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
26
|
Su X, Wang Y, Guo X, Dong Y, Gao Y, Sun X. Recovery of Sm(III), Co(II) and Cu(II) from waste SmCo magnet by ionic liquid-based selective precipitation process. Waste Manag 2018; 78:992-1000. [PMID: 32559995 DOI: 10.1016/j.wasman.2018.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 06/14/2018] [Accepted: 07/02/2018] [Indexed: 06/11/2023]
Abstract
Recovery of secondary resources including waste SmCo magnets contributes to easing the natural resources and environmental issues. For the development of recovery technologies, an ionic liquid (IL)-based precipitation route based on [trihexyl(tetradecyl)phosphonium]2[benzene-1,4-dioxydiacetate] ([P6,6,6,14]2[BDOAC]) is presented. The slow release of [BDOAC]2- from [P6,6,6,14]2[BDOAC] increases the kinetics difference in the formations of precipitates, and makes the precipitates contain less impurity. While cobalt-rich solution is obtained with no loss, precipitation efficiency of Sm(III) and Cu(II) reaches 96.8% and 100% respectively. Afterwards, Cu(II) is removed using aqueous ammonia and pure Cu(II) (96.4% precipitation efficiency) is obtained by adjusting the pH of cuprammonium complex solution. The proposed process without volatile diluent reveals higher separation factors of Sm/Co, Cu/Co and Sm/Cu. Lower acidities are efficient for the complete stripping of Sm(III) and Cu(II) from their precipitates. SmCl3 and CuCl2 solutions are obtained both with the high purities. Moreover, the IL-based precipitant can be regenerative. It is shown that the strategy is efficient for recovering and separating Sm, Co and Cu from the simulated leaching solution of waste SmCo magnets.
Collapse
Affiliation(s)
- Xiang Su
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China; University of Chinese Academy of Sciences, Beijing 100039, PR China.
| | - Yanliang Wang
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
| | - Xiangguang Guo
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
| | - Yamin Dong
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
| | - Yun Gao
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
| | - Xiaoqi Sun
- CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China; Ganzhou Rare Earth Group Co., Ltd., China Southern Rare Earth, Ganzhou 341000, PR China.
| |
Collapse
|
27
|
Silva WC, de Souza Corrêa R, da Silva CSM, Afonso JC, da Silva RS, Vianna CA, Mantovano JL. Recovery of base metals, silicon and fluoride ions from mobile phone printed circuit boards after leaching with hydrogen fluoride and hydrogen peroxide mixtures. Waste Manag 2018; 78:781-788. [PMID: 32559970 DOI: 10.1016/j.wasman.2018.06.049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 05/21/2018] [Accepted: 06/25/2018] [Indexed: 06/11/2023]
Abstract
The recovery of copper, nickel, zinc, silicon, iron, aluminum, tin and fluoride ions from fluoride leach liquors of non-ground printed circuit boards (PCBs) from mobile phones is described in detail. These PCBs were leached with HF + H2O2 mixtures after previous treatment with 6 mol L-1 NaOH (removal of the solder mask). A combination of solvent extraction (SX) and precipitation techniques was used. 99.5 wt% zinc, copper and nickel, in this order, were extracted in one stage (Zn, Ni) or two stages (Cu) with di-2-ethylhexylphosphoric acid (D2EHPA) diluted in kerosene (25 °C, A/O = 1 v/v) after adjusting the pH of the leachate. They were easily stripped by aqueous H2SO4. Iron, aluminum and tin did not interfere because they were masked by fluoride ions. Iron and aluminum were precipitated together as Na3FeF6 + Na3AlF6 by careful addition of aqueous NaOH. Silicon, tin and fluoride ions were recovered together (Na2SiF6 + Na2SnF6 + NaF) by careful evaporation of the aqueous solution after SX of nickel. The tin salt was leached from this solid by absolute ethanol. High HF concentration (10 mol L-1) in the leachant affected SX of Cu(II) and precipitation of iron/aluminum flurocomplexes since some NaF partially precipitated at acidic pH.
Collapse
Affiliation(s)
- Walner Costa Silva
- Analytical Chemistry Department, Institute of Chemistry, Federal University of Rio de Janeiro, Av. Athos da Silveira Ramos, 149, Room A509, 21941-909 Ilha do Fundão, Rio de Janeiro, Brazil
| | - Roger de Souza Corrêa
- Analytical Chemistry Department, Institute of Chemistry, Federal University of Rio de Janeiro, Av. Athos da Silveira Ramos, 149, Room A509, 21941-909 Ilha do Fundão, Rio de Janeiro, Brazil
| | - Calvin Sampaio Moreira da Silva
- Analytical Chemistry Department, Institute of Chemistry, Federal University of Rio de Janeiro, Av. Athos da Silveira Ramos, 149, Room A509, 21941-909 Ilha do Fundão, Rio de Janeiro, Brazil
| | - Júlio Carlos Afonso
- Analytical Chemistry Department, Institute of Chemistry, Federal University of Rio de Janeiro, Av. Athos da Silveira Ramos, 149, Room A509, 21941-909 Ilha do Fundão, Rio de Janeiro, Brazil.
| | - Rubens Souza da Silva
- Chemistry and Nuclear Materials Department, Institute of Nuclear Engineering, Rua Hélio de Almeida, 75, 21941-906 Ilha do Fundão, Rio de Janeiro, Brazil
| | - Cláudio Augusto Vianna
- Chemistry and Nuclear Materials Department, Institute of Nuclear Engineering, Rua Hélio de Almeida, 75, 21941-906 Ilha do Fundão, Rio de Janeiro, Brazil
| | - José Luiz Mantovano
- Chemistry and Nuclear Materials Department, Institute of Nuclear Engineering, Rua Hélio de Almeida, 75, 21941-906 Ilha do Fundão, Rio de Janeiro, Brazil
| |
Collapse
|
28
|
Affiliation(s)
- Pablo Dias
- Universidade Federal do Rio Grande do Sul (UFRGS), Brazil
| | | | - Hugo Veit
- Universidade Federal do Rio Grande do Sul (UFRGS), Brazil
| |
Collapse
|
29
|
Wansi E, D’Ans P, Gonda L, Segato T, Degrez M. Waste Management of Discarded Cell Phones and Proposal of Material Recovery Techniques. ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.procir.2017.11.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
30
|
Kasper AC, Veit HM, García-Gabaldón M, Herranz VP. Electrochemical study of gold recovery from ammoniacal thiosulfate, simulating the PCBs leaching of mobile phones. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2017.10.161] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
31
|
Kang H, Shao Q, Guo X, Galaska A, Liu Y, Guo Z. Separation and Recovery of Copper Foil and Fabric from Waste Printed Circuit Boards by Decomposing Brominated Epoxy Resin Using Near Critical Water. ACTA ACUST UNITED AC 2018. [DOI: 10.30919/espub.es.180312] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
32
|
Silveira A, Santana M, Tanabe E, Bertuol D. Recovery of valuable materials from spent lithium ion batteries using electrostatic separation. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.minpro.2017.11.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
33
|
Priya A, Hait S. Qualitative and quantitative metals liberation assessment for characterization of various waste printed circuit boards for recycling. Environ Sci Pollut Res Int 2017; 24:27445-27456. [PMID: 28980132 DOI: 10.1007/s11356-017-0351-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Abstract
Metals liberation and composition are decisive attributes in characterization of e-waste for metal recycling. Though end-of-life printed circuit board (PCB) is an integral part of e-waste as secondary resource reservoir, yet no standardized procedure exists for metals liberation and dissolution for its characterization. Thus, the paper aims at assessment of metals liberation upon comminution employing scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) followed by comparative assessment of the existing United States Environmental Protection Agency (USEPA) digestion procedures, viz., USEPA 3050B, USEPA 3051A, and USEPA 3052, in effective dissolution of metals from comminuted particles of waste PCBs of computer, laptop, mobile phone, and television. Effect of comminution and digestion conditions was assessed to have significant role in metal liberation and dissolution from PCBs. The SEM-EDS analysis demonstrated partial release of metals from the silica matrix of PCBs. The USEPA digestion methods showed statistically significant (P < 0.05) difference with greater dissolution of metals complexed to PCB matrix by the USEPA 3052 method owing to use of strong acid like hydrofluoric acid. Base metals like Cu and Zn and toxic metals such as Pb and Cd were present in abundance in PCBs and in general exceeded the total threshold limit concentration (TTLC). The maximum contents of Cu (20.13 ± 0.04 wt.%) and Zn (1.89 ± 0.05 wt.%) in laptop PCBs, Pb (2.26 ± 0.08 wt.%) in TV PCBs, and Cd (0.0812 ± 0.0008 wt.%) in computer PCBs were observed.
Collapse
Affiliation(s)
- Anshu Priya
- Department of Civil and Environmental Engineering, Indian Institute of Technology Patna, Bihta, Patna, Bihar, 801 103, India
| | - Subrata Hait
- Department of Civil and Environmental Engineering, Indian Institute of Technology Patna, Bihta, Patna, Bihar, 801 103, India.
| |
Collapse
|
34
|
Calgaro CO, Schlemmer DF, Bassaco MM, Dotto GL, Tanabe EH, Bertuol DA. Supercritical extraction of polymers from printed circuit boards using CO2 and ethanol. J CO2 UTIL 2017. [DOI: 10.1016/j.jcou.2017.10.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
|
35
|
Raele MP, De Pretto LR, Zezell DM. Soldering mask laser removal from printed circuit boards aiming copper recycling. Waste Manag 2017; 68:475-481. [PMID: 28739025 DOI: 10.1016/j.wasman.2017.07.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 07/08/2017] [Accepted: 07/12/2017] [Indexed: 06/07/2023]
Abstract
Management of waste of electric and electronic equipment (WEEE) is a key issue for modern societies; furthermore, it contains valuable materials that can be recycled, especially in printed circuit boards (PCB), which have approximately one-third of their weight in copper. In this study we demonstrated the use of laser to strip the covering soldering mask on PCB's, thus exposing the copper underneath so that extraction techniques may take place. Using a Q-Switched Nd:YAG laser operating at 1064nm and 532nm we tested the procedure under different energy conditions. The laser stripping of the soldering mask was achieved with satisfactory results by irradiation with 225mJ at 1064nm. However, when using similar parameters at 532nm the process of the coating ejection was not promoted properly, leading to a faulty detachment. Infrared laser PCB stripping presents itself to be technically viable and environmental friendly, since it uses no chemicals inputs, offering one more option to WEEE treatment and recycling.
Collapse
Affiliation(s)
- Marcus Paulo Raele
- Nuclear and Energy Research Institute, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242 Cidade Universitária, CEP 05508-000 São Paulo, SP, Brazil.
| | - Lucas Ramos De Pretto
- Nuclear and Energy Research Institute, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242 Cidade Universitária, CEP 05508-000 São Paulo, SP, Brazil
| | - Denise Maria Zezell
- Nuclear and Energy Research Institute, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242 Cidade Universitária, CEP 05508-000 São Paulo, SP, Brazil
| |
Collapse
|
36
|
Li J, Ge Z, Liang C, An N. Present status of recycling waste mobile phones in China: a review. Environ Sci Pollut Res Int 2017; 24:16578-16591. [PMID: 28555392 DOI: 10.1007/s11356-017-9089-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Accepted: 04/24/2017] [Indexed: 06/07/2023]
Abstract
A large number of waste mobile phones have already been generated and are being generated. Various countries around the world have all been positively exploring the way of recycling and reuse when facing such a large amount of waste mobile phones. In some countries, processing waste mobile phones has been forming a complete industrial chain, which can not only recycle waste mobile phones to reduce their negative influence on the environment but also turn waste into treasure to acquire economic benefits dramatically. However, the situation of recycling waste mobile phones in China is not going well. Waste mobile phones are not formally covered by existing regulations and policies for the waste electric and electronic equipment in China. In order to explore an appropriate system to recover waste mobile phones, the mobile phone production and the amount of waste mobile phones are introduced in this paper, and status of waste mobile phones recycling is described; then, the disposal technology of electronic waste that would be most likely to be used for processing of electronic waste in industrial applications in the near future is reviewed. Finally, rationalization proposals are put forward based on the current recovery status of waste mobile phones for the purpose of promoting the development of recycling waste mobile phones in developing countries with a special emphasis on China.
Collapse
Affiliation(s)
- Jingying Li
- College of Environment and Safety Engineering, Qingdao University of Science & Technology, Qingdao, 266042, Shandong, People's Republic of China.
| | - Zhongying Ge
- College of Environment and Safety Engineering, Qingdao University of Science & Technology, Qingdao, 266042, Shandong, People's Republic of China
| | | | - Ni An
- College of Environment and Safety Engineering, Qingdao University of Science & Technology, Qingdao, 266042, Shandong, People's Republic of China
| |
Collapse
|
37
|
|
38
|
Martino R, Iseli C, Gaydardzhiev S, Streicher-Porte M, Weh A. Characteristics of End-of-Life Printed Wiring Boards Processed by Electrodynamic Fragmentation. CHEM-ING-TECH 2016. [DOI: 10.1002/cite.201600091] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
39
|
Dias P, Javimczik S, Benevit M, Veit H, Bernardes AM. Recycling WEEE: Extraction and concentration of silver from waste crystalline silicon photovoltaic modules. Waste Manag 2016; 57:220-225. [PMID: 26980485 DOI: 10.1016/j.wasman.2016.03.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 03/08/2016] [Accepted: 03/09/2016] [Indexed: 06/05/2023]
Abstract
Photovoltaic modules (or panels) are important power generators with limited lifespans. The modules contain known pollutants and valuable materials such as silicon, silver, copper, aluminum and glass. Thus, recycling such waste is of great importance. To date, there have been few published studies on recycling silver from silicon photovoltaic panels, even though silicon technology represents the majority of the photovoltaic market. In this study, the extraction of silver from waste modules is justified and evaluated. It is shown that the silver content in crystalline silicon photovoltaic modules reaches 600g/t. Moreover, two methods to concentrate silver from waste modules were studied, and the use of pyrolysis was evaluated. In the first method, the modules were milled, sieved and leached in 64% nitric acid solution with 99% sodium chloride; the silver concentration yield was 94%. In the second method, photovoltaic modules were milled, sieved, subjected to pyrolysis at 500°C and leached in 64% nitric acid solution with 99% sodium chloride; the silver concentration yield was 92%. The first method is preferred as it consumes less energy and presents a higher yield of silver. This study shows that the use of pyrolysis does not assist in the extraction of silver, as the yield was similar for both methods with and without pyrolysis.
Collapse
Affiliation(s)
- Pablo Dias
- Programa de Pós-Graduação em Engenharia de Minas, Metalúrgica e de Materiais (PPGE3M), Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, 91509-900 Porto Alegre, RS, Brazil.
| | - Selene Javimczik
- Programa de Pós-Graduação em Engenharia de Minas, Metalúrgica e de Materiais (PPGE3M), Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, 91509-900 Porto Alegre, RS, Brazil
| | - Mariana Benevit
- Programa de Pós-Graduação em Engenharia de Minas, Metalúrgica e de Materiais (PPGE3M), Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, 91509-900 Porto Alegre, RS, Brazil
| | - Hugo Veit
- Programa de Pós-Graduação em Engenharia de Minas, Metalúrgica e de Materiais (PPGE3M), Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, 91509-900 Porto Alegre, RS, Brazil.
| | - Andréa Moura Bernardes
- Programa de Pós-Graduação em Engenharia de Minas, Metalúrgica e de Materiais (PPGE3M), Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, 91509-900 Porto Alegre, RS, Brazil
| |
Collapse
|
40
|
Ou ZJ, Li J. The geochemically-analogous process of metal recovery from second-hand resources via mechanochemistry: An atom-economic case study and its implications. Waste Manag 2016; 57:57-63. [PMID: 27575028 DOI: 10.1016/j.wasman.2016.08.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 08/16/2016] [Accepted: 08/16/2016] [Indexed: 06/06/2023]
Abstract
In the context of recycling metal to embrace the sustainability challenge, this work proposes a geochemically-analogous process of metal recovery through mechanochemistry for the first time, to avoid the limitations of on-going methods and to establish an innovative technology philosophy. This work systematically investigates this geochemically-analogous process, to keep it green and to generalize it further. Copper recovery from waste printed circuit boards (WPCBs), a typical copper-rich waste, is chosen as a case study in this work. Nearly 98% of the copper in the WPCBs can be recycled in the optimized conditions and 82.3% of the sulfur can be reused, by means of the process. Based on the experimental result, this paper purports a closed-loop route of copper recovery which follows the green chemistry principles (high yield, high atom economy and no secondary pollution). This route can be generalized into other second-hand resources that are rich in copper. Some other metals (e.g. lead) that are commonly present as corresponding sulfides in nature can be taken into consideration in this geochemically-analogous process as well.
Collapse
Affiliation(s)
- Zhiyuan James Ou
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China.
| | - Jinhui Li
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China
| |
Collapse
|
41
|
Arshadi M, Mousavi SM, Rasoulnia P. Enhancement of simultaneous gold and copper recovery from discarded mobile phone PCBs using Bacillus megaterium: RSM based optimization of effective factors and evaluation of their interactions. Waste Manag 2016; 57:158-167. [PMID: 27264460 DOI: 10.1016/j.wasman.2016.05.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 04/25/2016] [Accepted: 05/10/2016] [Indexed: 05/24/2023]
Abstract
Bioleaching of Au from mobile phone printed circuit boards (MPPCBs) was studied, using Bacillus megaterium which is a cyanogenic bacterium. To maximize Au extraction, initial pH, pulp density, and glycine concentration were optimized via response surface methodology (RSM). Bioleaching of Cu, an important inhibitor on Au recovery, was also examined. To maximize Au recovery, the optimal condition suggested by the models was initial pH of 10, pulp density of 8.13g/l, and glycine concentration of 10g/l. Under the optimal condition, approximately 72% of Cu and 65g Au/ton MPPCBs, which is 7 times greater than the recovery from gold mines, was extracted. Cu elimination from the MPPCBs having a rich content of Au did not cause a significant effect on Au recovery. It was found that when the ratio of Cu to Au is high, Cu elimination can considerably improve Au recovery. B. megaterium could extract the total Au from PCBs containing 130g Au/ton MPPCBs.
Collapse
Affiliation(s)
- M Arshadi
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran
| | - S M Mousavi
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran.
| | - P Rasoulnia
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran
| |
Collapse
|
42
|
Kaya M. Recovery of metals and nonmetals from electronic waste by physical and chemical recycling processes. Waste Manag 2016; 57:64-90. [PMID: 27543174 DOI: 10.1016/j.wasman.2016.08.004] [Citation(s) in RCA: 205] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Revised: 08/02/2016] [Accepted: 08/04/2016] [Indexed: 05/11/2023]
Abstract
This paper reviews the existing and state of art knowledge for electronic waste (e-waste) recycling. Electrical and/or electronic devices which are unwanted, broken or discarded by their original users are known as e-waste. The main purpose of this article is to provide a comprehensive review of e-waste problem, strategies of e-waste management and various physical, chemical and metallurgical e-waste recycling processes, their advantages and disadvantages towards achieving a cleaner process of waste utilization, with special attention towards extraction of both metallic values and nonmetallic substances. The hazards arise from the presence of heavy metals Hg, Cd, Pb, etc., brominated flame retardants (BFRs) and other potentially harmful substances in e-waste. Due to the presence of these substances, e-waste is generally considered as hazardous waste and, if improperly managed, may pose significant human and environmental health risks. This review describes the potential hazards and economic opportunities of e-waste. Firstly, an overview of e-waste/printed circuit board (PCB) components is given. Current status and future perspectives of e-waste/PCB recycling are described. E-waste characterization, dismantling methods, liberation and classification processes are also covered. Manual selective dismantling after desoldering and metal-nonmetal liberation at -150μm with two step crushing are seen to be the best techniques. After size reduction, mainly physical separation processes employing gravity, electrostatic, magnetic separators, froth floatation, etc. have been critically reviewed here for separation of metals and nonmetals, along with useful utilizations of the nonmetallic materials. The recovery of metals from e-waste material after physical separation through pyrometallurgical, hydrometallurgical or biohydrometallurgical routes is also discussed along with purification and refining. Suitable PCB recycling flowsheets for industrial applications are also given. It seems that hydrometallurgical route will be a key player in the base and precious metals recoveries from e-waste. E-waste recycling will be a very important sector in the near future from economic and environmental perspectives. Recycling technology aims to take today's waste and turn it into conflict-free, sustainable polymetallic secondary resources (i.e. Urban Mining) for tomorrow. Recycling technology must ensure that e-waste is processed in an environmentally friendly manner, with high efficiency and lowered carbon footprint, at a fraction of the costs involved with setting multibillion dollar smelting facilities. Taking into consideration our depleting natural resources, this Urban Mining approach offers quite a few benefits. This results in increased energy efficiency and lowers demand for mining of new raw materials.
Collapse
Affiliation(s)
- Muammer Kaya
- Mining Engineering Department, Eskişehir Osmangazi University, Eskişehir, Turkey.
| |
Collapse
|
43
|
Vlachos IP. Reverse logistics capabilities and firm performance: the mediating role of business strategy. International Journal of Logistics Research and Applications 2016. [DOI: 10.1080/13675567.2015.1115471] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
44
|
Kumar A, Choudhary V, Khanna R, Tripathi SN, Ikram-Ul-Haq M, Sahajwalla V. Structural, thermal, morphological and dynamic mechanical characteristics of waste-reinforced polypropylene composites: A novel approach for recycling electronic waste. J Appl Polym Sci 2016. [DOI: 10.1002/app.43389] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Abhishek Kumar
- Centre for Polymer Science and Engineering; Indian Institute of Technology; New Delhi 110016 India
| | - Veena Choudhary
- Centre for Polymer Science and Engineering; Indian Institute of Technology; New Delhi 110016 India
| | - Rita Khanna
- Centre for Sustainable Materials Research and Technology (SMaRT); School of Materials Science and Engineering, The University of New South Wales; Sydney 2052 Australia
| | - Sandeep Nath Tripathi
- Centre for Polymer Science and Engineering; Indian Institute of Technology; New Delhi 110016 India
| | - M. Ikram-Ul-Haq
- Centre for Sustainable Materials Research and Technology (SMaRT); School of Materials Science and Engineering, The University of New South Wales; Sydney 2052 Australia
| | - Veena Sahajwalla
- Centre for Sustainable Materials Research and Technology (SMaRT); School of Materials Science and Engineering, The University of New South Wales; Sydney 2052 Australia
| |
Collapse
|
45
|
Kasper AC, Carrillo Abad J, García Gabaldón M, Veit HM, Pérez Herranz V. Determination of the potential gold electrowinning from an ammoniacal thiosulphate solution applied to recycling of printed circuit board scraps. Waste Manag Res 2016; 34:47-57. [PMID: 26437680 DOI: 10.1177/0734242x15607425] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The use of electrochemical techniques in the selective recovery of gold from a solution containing thiosulphate, ammonia, and copper, obtained from the leaching of printed circuit boards from mobile phones using ammoniacal thiosulphate, are shown in this work. First, cyclic voltammetry tests were performed to determine the potential of electrodeposition of gold and copper, and then, electrowinning tests at different potentials for checking the rates of recovery of these metals were performed. The results of the cyclic voltammetry show that copper deposition occurs at potentials more negative than -600 mV (Ag/AgCl), whereas the gold deposition can be performed at potentials more positives than -600 mV (Ag/AgCl). The results of electrowinning show that 99% of the gold present in solutions containing thiosulphate and copper can be selectively recovered in a potential range between -400 mV (vs Ag/AgCl) and -500 mV (vs Ag/AgCl). Furthermore, 99% of copper can be recovered in potentials more negative than -700 mV (vs Ag/AgCl).
Collapse
Affiliation(s)
- Angela C Kasper
- LACOR-PPGE3M, Universidade Federal do Rio Grande do Sul, Rio Grande do Sul, Brazil
| | - Jordi Carrillo Abad
- Departamento de Ingeniería Química y Nuclear, Universidad Politécnica de Valencia, Valencia, Spain
| | | | - Hugo M Veit
- LACOR-PPGE3M, Universidade Federal do Rio Grande do Sul, Rio Grande do Sul, Brazil
| | - Valentín Pérez Herranz
- Departamento de Ingeniería Química y Nuclear, Universidad Politécnica de Valencia, Valencia, Spain
| |
Collapse
|
46
|
Zhang S, Yu Y. Dechlorination Behavior on the Recovery of Useful Resources from WEEE by the Steam Gasification in the Molten Carbonates. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.proenv.2016.02.108] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
47
|
Silvas FPC, Correa MMJ, Caldas MPK, de Moraes VT, Espinosa DCR, Tenório JAS. Printed circuit board recycling: Physical processing and copper extraction by selective leaching. Waste Manag 2015; 46:503-10. [PMID: 26323203 DOI: 10.1016/j.wasman.2015.08.030] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 08/20/2015] [Accepted: 08/20/2015] [Indexed: 05/22/2023]
Abstract
Global generation of waste electrical and electronic equipment (WEEE) is about 40 million tons per year. Constant increase in WEEE generation added to international legislations has improved the development of processes for materials recovery and sustainability of electrical and electronic industry. This paper describes a new hydrometallurgical route (leaching process) to recycle printed circuit boards (PCBs) from printers to recover copper. Methodology included PCBs characterization and a combined route of physical and hydrometallurgical processing. Magnetic separation, acid digestion and chemical analysis by ICP-OES were performed. On leaching process were used two stages: the first one in a sulfuric media and the second in an oxidant media. The results showed that the PCBs composition was 74.6 wt.% of non-magnetic material and 25.4 wt.% of magnetic one. The metallic fraction corresponded to 44.0 wt.%, the polymeric to 28.5 wt.% and the ceramic to 27.5 wt.%. The main metal was copper and its initial content was 32.5 wt.%. On sulfuric leaching 90 wt.% of Al, 40 wt.% of Zn and 8.6 wt.% of Sn were extracted, whereas on oxidant leaching tests the extraction percentage of Cu was 100 wt.%, of Zn 60 wt.% and of Al 10 wt.%. At the end of the hydrometallurgical processing was obtained 100% of copper extraction and the recovery factor was 98.46%, which corresponds to a 32 kg of Cu in 100 kg of PCB.
Collapse
Affiliation(s)
- Flávia P C Silvas
- Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil.
| | - Mónica M Jiménez Correa
- Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil.
| | - Marcos P K Caldas
- Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil; Federal Institute of Technology, Science and Education of Espírito Santo, Rd ES-010, Km 6,5 - Manguinhos, CEP 29173-087 Serra, ES, Brazil.
| | - Viviane T de Moraes
- Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil.
| | - Denise C R Espinosa
- Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil.
| | - Jorge A S Tenório
- Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil.
| |
Collapse
|
48
|
Sarath P, Bonda S, Mohanty S, Nayak SK. Mobile phone waste management and recycling: Views and trends. Waste Manag 2015; 46:536-545. [PMID: 26383903 DOI: 10.1016/j.wasman.2015.09.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 09/07/2015] [Accepted: 09/08/2015] [Indexed: 06/05/2023]
Abstract
There is an enormous growth in mobile phone consumption worldwide which leads to generation of a large volume of mobile phone waste every year. The aim of this review is to give an insight on the articles on mobile phone waste management and recycling, published in scientific journals, major proceedings and books from 1999 to 2015. The major areas of research have been identified and discussed based on available literature in each research topic. It was observed that most of these articles were published during the recent years, with the number of articles increasing yearly. Material recovery and review on management options of waste are found to be the leading topics in this area. Researchers have proved that economically viable refurbishing or recycling of such waste is possible in an environmentally friendly manner. However, the literatures indicate that without proper consumer awareness, a recycling system cannot perform to its maximum efficiency. The methodologies followed and analytical techniques employed by the researchers to attain their objectives have been discussed. The graphical representations of available literature on current topic with respect to year of publication, topics and location have also been explored.
Collapse
Affiliation(s)
- P Sarath
- Central Institute of Plastics Engineering and Technology (CIPET), TVK Industrial Estate, Guindy, Chennai 600032, Tamil Nadu, India.
| | - Sateesh Bonda
- Laboratory for Advanced Research in Polymeric Materials (LARPM), Central Institute of Plastics Engineering and Technology (CIPET), B-25, CNI Complex, Patia, Bhubaneswar 751024, Odisha, India
| | - Smita Mohanty
- Laboratory for Advanced Research in Polymeric Materials (LARPM), Central Institute of Plastics Engineering and Technology (CIPET), B-25, CNI Complex, Patia, Bhubaneswar 751024, Odisha, India
| | - Sanjay K Nayak
- Central Institute of Plastics Engineering and Technology (CIPET), TVK Industrial Estate, Guindy, Chennai 600032, Tamil Nadu, India; Laboratory for Advanced Research in Polymeric Materials (LARPM), Central Institute of Plastics Engineering and Technology (CIPET), B-25, CNI Complex, Patia, Bhubaneswar 751024, Odisha, India
| |
Collapse
|
49
|
Calgaro CO, Schlemmer DF, da Silva MDCR, Maziero EV, Tanabe EH, Bertuol DA. Fast copper extraction from printed circuit boards using supercritical carbon dioxide. Waste Manag 2015; 45:289-297. [PMID: 26022338 DOI: 10.1016/j.wasman.2015.05.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/12/2015] [Accepted: 05/12/2015] [Indexed: 06/04/2023]
Abstract
Technological development and intensive marketing support the growth in demand for electrical and electronic equipment (EEE), for which printed circuit boards (PCBs) are vital components. As these devices become obsolete after short periods, waste PCBs present a problem and require recycling. PCBs are composed of ceramics, polymers, and metals, particularly Cu, which is present in highest percentages. The aim of this study was to develop an innovative method to recover Cu from the PCBs of old mobile phones, obtaining faster reaction kinetics by means of leaching with supercritical CO2 and co-solvents. The PCBs from waste mobile phones were characterized, and evaluation was made of the reaction kinetics during leaching at atmospheric pressure and using supercritical CO2 with H2O2 and H2SO4 as co-solvents. The results showed that the PCBs contained 34.83 wt% of Cu. It was found that the supercritical extraction was 9 times faster, compared to atmospheric pressure extraction. After 20 min of supercritical leaching, approximately 90% of the Cu contained in the PCB was extracted using a 1:20 solid:liquid ratio and 20% of H2O2 and H2SO4 (2.5 M). These results demonstrate the efficiency of the process. Therefore the supercritical CO2 employment in the PCBs recycling is a promising alternative and the CO2 is environmentally acceptable and reusable.
Collapse
Affiliation(s)
- C O Calgaro
- Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
| | - D F Schlemmer
- Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
| | - M D C R da Silva
- Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
| | - E V Maziero
- Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
| | - E H Tanabe
- Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
| | - D A Bertuol
- Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
| |
Collapse
|
50
|
Sarvar M, Salarirad MM, Shabani MA. Characterization and mechanical separation of metals from computer Printed Circuit Boards (PCBs) based on mineral processing methods. Waste Manag 2015; 45:246-57. [PMID: 26143534 DOI: 10.1016/j.wasman.2015.06.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 06/09/2015] [Accepted: 06/11/2015] [Indexed: 05/22/2023]
Abstract
In this paper, a novel mechanical process is proposed for enriching metal content of computer Printed Circuit Boards (PCBs). The PCBs are crushed and divided into three different size fractions namely: -0.59, +0.59 to 1.68 and +1.68 mm. Wet jigging and froth flotation methods are selected for metal enrichment. The coarse size fraction (+1.68 mm) is processed by jigging. The plastic free product is grinded and screened. The oversized product is separated as the first concentrate. It was rich of metal because the grinding process was selective. The undersized product is processed by froth flotation. Based on the obtained results, the middle size fraction (+0.59 to 1.68 mm) and the small size fraction (-0.59 mm) are processed by wet jigging and froth flotation respectively. The wet jigging process is optimized by investigating the effect of pulsation frequency and water flow rate. The results of examining the effect of particle size, solid to liquid ratio, conditioning time and using apolar collector showed that collectorless flotation is a promising method for separating nonmetals of PCBs. 95.6%, 97.5% and 85% of metal content of coarse size, middle size and small size fraction are recovered. The grades of obtained concentrates were 63.3%, 92.5% and 75% respectively. The total recovery is calculated as 95.64% and the grade of the final concentrate was 71.26%. Determining the grade of copper and gold in the final product reveals that 4.95% of copper and 24.46% of gold are lost during the concentration. The major part of the lost gold is accumulated in froth flotation tail.
Collapse
Affiliation(s)
- Mojtaba Sarvar
- Department of Mining and Metallurgical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
| | - Mohammad Mehdi Salarirad
- Department of Mining and Metallurgical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
| | - Mohammad Amin Shabani
- Department of Mining and Metallurgical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
| |
Collapse
|