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Zhu S, Zhang Y, Xin L, Htet Oo K, Zheng M, Ma S, Guo J, Chen Y. Near-complete recycling of real mix electroplating sludge as valuable metals via Fe/Cr co-crystallization and stepwise extraction route. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 358:120821. [PMID: 38599087 DOI: 10.1016/j.jenvman.2024.120821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 03/24/2024] [Accepted: 04/01/2024] [Indexed: 04/12/2024]
Abstract
In electroplating sludge, iron (Fe) and aluminum (Al) are common impurities that need to be separated before recycling valuable heavy metals. However, the traditional Fe/Al separation process often leads to significant losses of heavy metals. To address this issue, a new approach was developed to sequentially separate Fe/Al and recycle chromium (Cr) and nickel (Ni) from real electroplating sludge. The sludge contained 4.5% Cr, 1.2% Al, 1.1% Ni, and 14.6% Fe. Initially, the sludge was completely dissolved in a mixture of hydrochloric and nitric acids. The resulting acid solution was then heated to 160 °C for 10 h with the addition of saccharose. This hydrothermal treatment led to the hydrolysis and crystallization of 98.3% of Fe, 31.8% of Cr, 1.1% of Al, and 4.9% of Ni, forming akaganeite-bearing particles. It was observed that the excessive amount of saccharose also improved the removal of Cr, Al, and Ni, but decreased the removal of Fe. After the hydrothermal treatment, the remaining supernatant was adjusted to different pH levels (1.9, 2.9, and 4.5, respectively), and then Al, Cr, and Ni were stepwise extracted using di-(2-ethylhexyl) phosphate acid (P204). The recycling efficiencies achieved were 97.4% for Al, 61.2% for Cr, and 89.3% for Ni. This approach provides a promising method for the stepwise separation of Fe/Al and the recycling of heavy metals from electroplating sludge.
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Affiliation(s)
- Suiyi Zhu
- Zhongkai University of Agriculture and Engineering, 501-Zhongkai Road, Guangzhou, China
| | - Yuxin Zhang
- School of Environment, Northeast Normal University, 2555-Jingyue Road, Changchun, China
| | - Lan Xin
- Zhongkai University of Agriculture and Engineering, 501-Zhongkai Road, Guangzhou, China
| | - Kaung Htet Oo
- School of Environment, Northeast Normal University, 2555-Jingyue Road, Changchun, China
| | - Minglin Zheng
- Zhongkai University of Agriculture and Engineering, 501-Zhongkai Road, Guangzhou, China
| | - Shengyao Ma
- School of Environment, Northeast Normal University, 2555-Jingyue Road, Changchun, China
| | - Jiayi Guo
- School of Municipal and Environmental Engineering, Jilin Jianzhu University, 5088-Xincheng Avenue, Changchun, China
| | - Yu Chen
- Zhongkai University of Agriculture and Engineering, 501-Zhongkai Road, Guangzhou, China.
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2
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Xiao Y, Li L, He J, Sun Y, Lei Y. A metallurgical approach for separation and recovery of Cu, Cr, and Ni from electroplating sludge. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 921:171130. [PMID: 38401729 DOI: 10.1016/j.scitotenv.2024.171130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 02/18/2024] [Accepted: 02/18/2024] [Indexed: 02/26/2024]
Abstract
Electroplating sludge is extensively produced in chemical precipitation-based treatment of electroplating wastewater. It poses a huge threat to environmental safety if not properly disposed, ascribed to its high contents of heavy metals. An innovative metallurgical approach was proposed a to recycle Cu, Cr, and Ni from it. Ammonia leaching was firstly performed to selectively leach Cu from Cr, in which the Cu oxide and sulfide were leached into the leachate while the Cr oxide and Ni carbide (NiCx) retained in the residue. (NH4)2SO4 increased the Cu leaching rate via increasing the dissolved oxygen amount in the ammonia leachate and converting CuS to Cu2+. Under the optimal conditions, the leaching efficiency of Cu achieved 96.5 % while that of Cr was only 0.1 %. In the followed aluminothermic reduction, C in the leaching residue could be effectively removed via a thermal oxidation, which in turn decreased the formation of a C-containing compound of high melting point and benefited the Cr and Ni recovery. Cr and Ni from the residue were reduced and recovered in a Cr-Ni alloy, and the reductant of Al first changed to a refractory Al2O3 and then transformed to a low melting point 12CaO·7Al2O3 with the additive of CaO. This transformation increased the molten slag fluidity and promoted the separation of Cr-Ni alloy from slag. Moreover, the excessive Al increased the Cr and Ni yields and concentrated all of them to be together. Partial Al was used as reductant, and the other Al transferred into Cr-Ni alloy to decrease its melting point. Cr and Ni contents in the smelting slag could be decreased to 0.11 wt% and 0.12 wt% respectively, showing an efficient recovery. This work provided a high efficiency method to recover Cu, Cr, and Ni from waste electroplating sludge.
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Affiliation(s)
- Yang Xiao
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China
| | - Lei Li
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
| | - Junli He
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China
| | - Yixuan Sun
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China
| | - Yun Lei
- Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, PR China
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3
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Guo S, Wang H, Liu X, Zhang Z, Liu Y. Approaches for the Treatment and Resource Utilization of Electroplating Sludge. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1707. [PMID: 38612220 PMCID: PMC11013125 DOI: 10.3390/ma17071707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/03/2024] [Accepted: 04/04/2024] [Indexed: 04/14/2024]
Abstract
The disposal of electroplating sludge (ES) is a major challenge for the sustainable development of the electroplating industry. ESs have a significant environmental impact, occupying valuable land resources and incurring high treatment costs, which increases operational expenses for companies. Additionally, the high concentration of hazardous substances in ES poses a serious threat to both the environment and human health. Despite extensive scholarly research on the harmless treatment and resource utilization of ES, current technology and processes are still unable to fully harness its potential. This results in inefficient resource utilization and potential environmental hazards. This article analyzes the physicochemical properties of ES, discusses its ecological hazards, summarizes research progress in its treatment, and elaborates on methods such as solidification/stabilization, heat treatment, wet metallurgy, pyrometallurgy, biotechnology, and material utilization. It provides a comparative summary of different treatment processes while also discussing the challenges and future development directions for technologies aimed at effectively utilizing ES resources. The objective of this text is to provide useful information on how to address the issue of ES treatment and promote sustainable development in the electroplating industry.
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Affiliation(s)
- Song Guo
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; (S.G.); (H.W.)
| | - Huimin Wang
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; (S.G.); (H.W.)
| | - Xiaoming Liu
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; (S.G.); (H.W.)
- State Key Laboratory of Advanced Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Zengqi Zhang
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; (S.G.); (H.W.)
| | - Yu Liu
- China International Engineering Consulting Corporation, Beijing 100048, China;
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Heng W, Yong Y, Jianhang H, Hua W. A novel method for effective solidifying chromium and preparing crude stainless steel from multi-metallic electroplating sludge. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133068. [PMID: 38043422 DOI: 10.1016/j.jhazmat.2023.133068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 12/05/2023]
Abstract
Electroplating sludge (ES) is a globally prevalent hazardous waste that primarily contains Cr, Cu, Ni, and Fe. However, the residual Cr phases within the slag potentially poses an environmental risk in current vitrification. A novel method for effective recovering and solidifying Cr in ES is proposed in this work. ES was desulfurized and subsequently co-treated with ferrosilicon (Fe-Si) and spent carbon anode (SCA) for enhancing the recovery of Cr, Cu, Ni, and Fe to prepare crude stainless steel. Under optimal conditions, the recovery ratios of Cr, Cu, Ni, and Fe reached 96.96%, 99.45%, 99.92%, and 99.20%, respectively, signifying improvements of 21.4%, 0.2%, 1.5%, and 2.8%, respectively, compared with existing research. Meanwhile, the fluoride in SCA yielded CaF2, further progressing to the Si-Ca-F-Na-Al-O phase, with a solidification ratio of 97.87%. The Cr leaching content of the residual Cr-Cu-S phase in the slag remained below 5 mg/L across a pH range of 2-4, demonstrating enhanced stability compared to prior alloy, oxide, and chemically dissolved phases. An innovative approach for solidify Cr by forming matte holds implications for the treatment of Cr-containing solid wastes such as chromium slag, tannery sludge and stainless steel slag.
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Affiliation(s)
- Wang Heng
- Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction, Ministry of Education, Kunming University of Science and Technology, Kunming, China; State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, China; National Local Joint Engineering Research Center of Energy Saving and Environmental Protection Technology in Metallurgy and Chemical Engineering Industry, Kunming University of Science and Technology, Kunming, China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, China
| | - Yu Yong
- Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction, Ministry of Education, Kunming University of Science and Technology, Kunming, China; State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, China; National Local Joint Engineering Research Center of Energy Saving and Environmental Protection Technology in Metallurgy and Chemical Engineering Industry, Kunming University of Science and Technology, Kunming, China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, China.
| | - Hu Jianhang
- Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction, Ministry of Education, Kunming University of Science and Technology, Kunming, China; State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, China; National Local Joint Engineering Research Center of Energy Saving and Environmental Protection Technology in Metallurgy and Chemical Engineering Industry, Kunming University of Science and Technology, Kunming, China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, China
| | - Wang Hua
- Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction, Ministry of Education, Kunming University of Science and Technology, Kunming, China; State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, China; National Local Joint Engineering Research Center of Energy Saving and Environmental Protection Technology in Metallurgy and Chemical Engineering Industry, Kunming University of Science and Technology, Kunming, China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, China
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5
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Wang H, Liu X, Zhang Z. Approaches for electroplating sludge treatment and disposal technology: Reduction, pretreatment and reuse. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 349:119535. [PMID: 37979382 DOI: 10.1016/j.jenvman.2023.119535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 10/29/2023] [Accepted: 11/04/2023] [Indexed: 11/20/2023]
Abstract
Electroplating sludge (ES) has become an obstacle to the sustainable development of the electroplating industry. Electroplating sludge has a large storage capacity, with a high concentration of soluble pollutants (heavy metals), which has great potential to harm the local ecosystems and human health. Although much research has been done in this area, there seems to be no mature and stable solution. Therefore, the latest technologies for the reduction, pretreatment and reuse of electroplating sludge are emphatically introduced based on the analysis of the characteristics of electroplating sludge and its impact on the ecological environment. The factors hindering the treatment and disposal of electroplating sludge are pointed out, and reasonable and feasible suggestions to solve this problem are proposed. The solidification and removal mechanism of heavy metals in electroplating sludge is emphatically analyzed. The physicochemical and separation processes of heavy metals, as well as thermal treatment technique are discussed. Finally, it is proposed to establish a database of the physicochemical properties and elemental content of electroplating sludge to achieve its systematic treatment and digestion. We hope that this paper can help solve the problem of electroplating sludge and promote the sustainable development of the electroplating industry.
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Affiliation(s)
- Huimin Wang
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Xiaoming Liu
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, 100083, China; School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
| | - Zengqi Zhang
- State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, 100083, China; School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing, 100083, China
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6
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Qu Z, Chen Y, Chen Y, Zhu S, Liu J, Ren H, Su T, Huo M. Efficient separation of impurities Fe/Al/Ca and recovery of Zn from electroplating sludge using glucose as reductant. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 896:165202. [PMID: 37392894 DOI: 10.1016/j.scitotenv.2023.165202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 04/21/2023] [Accepted: 06/27/2023] [Indexed: 07/03/2023]
Abstract
Electroplating sludge (ES), a hazardous waste containing heavy metals and Fe/Al/Ca impurities, is conventionally disposed of in landfills. In this study, a pilot-scale vessel with an effective capacity of 20 L was applied to recycle Zn from real ES. The sludge contained 6.3 wt% Fe, 6.9 wt% Al, 2.6 wt% Si, 6.1 wt% Ca, and 17.6 wt% Zn and was treated using a four-step method. First, ES was dissolved in nitric acid after washing in a water bath at 75 °C for 3 h to produce an acidic solution with Fe, Al, Ca, and Zn concentrations of 4527.2, 3116.1, 3357.7, and 21,275 mg/L, respectively. Second, the acidic solution was added with glucose at an Mglucose/Mnitrate ratio of 0.08 and hydrothermally treated at 160 °C for 4 h. During this step, nearly 100 % Fe and 100 % Al were simultaneously removed as a mixture containing 53.1 wt% Fe2O3 and 45.7 wt% Al2O3. This process was repeated five times, during which the Fe/Al removal and Ca/Zn loss rates remained unchanged. Third, the residual solution was adjusted with sulfuric acid, and over 99 % Ca was removed as gypsum. The residual Fe, Al, Ca, and Zn concentrations were 0.44, 0.88, 52.59, and 31,177.1 mg/L, respectively. Finally, Zn in the solution was precipitated as ZnO with a concentration of 94.3 %. Economic calculations showed that each 1 t of ES processed created revenue of about $122. This is the first study of high-value metal resource recovery using real electroplating sludge at the pilot scale. This work highlights the pilot-scale application of resource utilization of real ES and provides new insights into the recycling of heavy metals from hazardous waste.
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Affiliation(s)
- Zhan Qu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Yu Chen
- Science and Technology Innovation Centre for Municipal Wastewater Treatment and Water Quality Protection, Northeast Normal University, Changchun 130117, China
| | - Yusen Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Suiyi Zhu
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong 510225, China.
| | - Junzhen Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Hongqiang Ren
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Ting Su
- Science and Technology Innovation Centre for Municipal Wastewater Treatment and Water Quality Protection, Northeast Normal University, Changchun 130117, China
| | - Mingxin Huo
- Science and Technology Innovation Centre for Municipal Wastewater Treatment and Water Quality Protection, Northeast Normal University, Changchun 130117, China
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7
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Xiang H, Cheng L, Liu W, Wang S, Zhang Y, Su L, Tan C, Li Y. Characteristics of leachate from refuse transfer stations in rural China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:3056-3069. [PMID: 35943652 DOI: 10.1007/s11356-022-22449-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 08/04/2022] [Indexed: 06/15/2023]
Abstract
The properties of leachate from refuse transfer stations (RTSs) in rural China were indefinite. In this study, a total of 14 leachate samples from RTSs in nine provinces of China were characterized for their pH, electric conductivity, chromaticity, concentration of organic substances, nitrogen distribution, volatile organic compounds (VOCs), organic phosphorous pesticide, and heavy metals. The structural composition of fluorescent dissolved organic matter (FDOM) was also determined. To evaluate the leachate pollution potential in this study, a leachate pollution index was derived and used. Chromium (Cr) was the most polluting heavy metal present in rural leachate. Ethanol and ethyl acetate were the most frequently detected VOCs at high concentrations. Three-dimensional fluorescence excitation-emission matrix spectra were used to characterize the FDOM. Three components, tryptophan (C1), tyrosine-like (C2), and humic acid- and fulvic acid-like (C3) substances, were identified from all 14 samples. Tryptophan was the major component of FDOM and present in 45.7% of the samples by calculating the fluorescence intensity percentage, on average. Pearson correlations revealed that the fluorescence intensity of C1 and C3 was strongly related to soluble chemical oxygen demand and dissolved oxygen carbon, while C2 had significant positive correlations with ammonia nitrogen and total phosphorus of the solid waste. This study provided detailed data and findings that could serve as a preliminary basis for broadening options for the treatment and management of leachate from rural RTSs in China.
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Affiliation(s)
- Huiming Xiang
- Ministry of Ecology and Environment, Nanjing Institute of Environmental Sciences, 8 Jiangwangmiao Street, Nanjing, 210042, People's Republic of China
| | - Le Cheng
- Ministry of Ecology and Environment, Nanjing Institute of Environmental Sciences, 8 Jiangwangmiao Street, Nanjing, 210042, People's Republic of China
- College of Civil Engineering and Transportation, Hohai University, No.1 Xikang Road, Nanjing, 210024, People's Republic of China
| | - Weiye Liu
- Ministry of Ecology and Environment, Nanjing Institute of Environmental Sciences, 8 Jiangwangmiao Street, Nanjing, 210042, People's Republic of China
- College of Civil Engineering and Transportation, Hohai University, No.1 Xikang Road, Nanjing, 210024, People's Republic of China
| | - Saier Wang
- Ministry of Ecology and Environment, Nanjing Institute of Environmental Sciences, 8 Jiangwangmiao Street, Nanjing, 210042, People's Republic of China
| | - Yi Zhang
- Ministry of Ecology and Environment, Nanjing Institute of Environmental Sciences, 8 Jiangwangmiao Street, Nanjing, 210042, People's Republic of China
| | - Lianghu Su
- Ministry of Ecology and Environment, Nanjing Institute of Environmental Sciences, 8 Jiangwangmiao Street, Nanjing, 210042, People's Republic of China.
| | - Chaoqun Tan
- Department of Municipal Engineering, Southeast University, Nanjing, 211189, People's Republic of China
| | - Yuping Li
- College of Civil Engineering and Transportation, Hohai University, No.1 Xikang Road, Nanjing, 210024, People's Republic of China.
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Kassab WA. Comparative study for leaching processes of uranium, copper and cadmium from gibbsite ore material of Talet Seleim, Southwestern, Sinai, Egypt. J Radioanal Nucl Chem 2022. [DOI: 10.1007/s10967-022-08727-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
AbstractIn this paper, leaching characteristics are presented, and a cost-effective process for extracting uranium, copper, and cadmium from Talet Seleim’s Gibbsite is developed. H2SO4 was chosen as the preferable leaching agent based on the agitation experiment’s findings. The leaching efficiencies of U, Cu, and Cd attained 95%, 90%, and 89%, respectively, under the investigated ideal circumstances. Kinetic study of leaching process proved diffusion controlling mechanisms with activation energies: 29.59, 29.30, and 34.84 kJ/mol, respectively. U was recovered using Amberlite IRA 400, while Cu and Cd were precipitated from Talet Seleim’s gibbsite’s sulphate leachate. Finally, the tentative treatment procedure's preliminary flowsheet was then given.
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Hou H, Xu S, Ding S, Lin W, Yu Q, Zhang J, Qian G. Electroplating sludge-derived metal and sulfur co-doping catalyst and its application in methanol production by CO 2 catalytic hydrogenation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156032. [PMID: 35597356 DOI: 10.1016/j.scitotenv.2022.156032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 05/13/2022] [Accepted: 05/13/2022] [Indexed: 06/15/2023]
Abstract
Electroplating sludge is a hazardous waste and its recycling is a hot topic. Electroplating sludge usually contains plenty of transition metals and multi-hetero atoms, which are potential resources. For the first time, this work synthesized spinel catalyst from Zn- and Cr-containing electroplating sludges by a simple calcination method, and applied the obtained catalysts in CH3OH production by CO2 catalytic hydrogenation. The spinel was doped by various heteroatoms, including Fe, Mn, Cu, and even S. According to detailed characterizations, the metal doping increased the low-temperature conversion efficiency of CO2 but decreased the CH3OH selectivity at the same time. After a further doping of S, although CO2 conversion efficiency was slightly decreased, the selectivity of CH3OH was significantly increased. After all, the optimized catalyst attained a conversion efficiency of 8.6% (CO2) as well as a selectivity of 73.3% (CH3OH) at 250 °C and 3 MPa. As a result, above results realized high-value-added utilization of hazardous waste and producing valuable product at the same time, which was in favor of circular development.
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Affiliation(s)
- Hao Hou
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, No. 381 Nanchen Road, Shanghai 200444, PR China; Shanghai Petrochemical Research Institute, No. 1658 Pudong North Road, Shanghai 201208, PR China
| | - Shichu Xu
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, No. 381 Nanchen Road, Shanghai 200444, PR China
| | - Suyan Ding
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, No. 381 Nanchen Road, Shanghai 200444, PR China
| | - Weijie Lin
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, No. 381 Nanchen Road, Shanghai 200444, PR China
| | - Qiang Yu
- Shanghai Petrochemical Research Institute, No. 1658 Pudong North Road, Shanghai 201208, PR China.
| | - Jia Zhang
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, No. 381 Nanchen Road, Shanghai 200444, PR China.
| | - Guangren Qian
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, No. 381 Nanchen Road, Shanghai 200444, PR China
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10
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Xiao Y, Li L, Huang M, Liu Y, Xu J, Xu Z, Lei Y. Treating waste with waste: Metals recovery from electroplating sludge using spent cathode carbon combustion dust and copper refining slag. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156453. [PMID: 35660588 DOI: 10.1016/j.scitotenv.2022.156453] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/21/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
Electroplating sludge is a hazardous waste and secondary metal resource because of its heavy metal content, which poses a huge threat to environmental safety if not properly disposed. An innovative process of oxidizing roasting followed by water leaching and smelting reduction to recover Cr, Cu, and Ni from electroplating sludge was proposed in this research, in which other two hazardous wastes of spent cathode carbon combustion dust and copper refining slag were co-treated. The NaF from spent cathode carbon combustion dust could convert Cr2O3 to Na2CrO4 using the oxidizing roasting process, resulting in a Cr recovery through the subsequent water leaching. The Na2CrO4 formation was promoted by CaO owing to it transferring the Cr spinel phase of FeCr2O4 [1+] to CaCrO4 and then to Na2CrO4. Under optimal conditions, the Cr recovery reached 97.1 %, and most 'F' was solidified into CaF2. In the next smelting reduction of the leaching residue, the Cu and Ni were recovered mainly in the form of Cu-Ni alloy. The addition of copper refining slag promoted their recovery, due to it modifying the molten slag and alloy structures and increasing the Cu-Ni alloy separation from molten slag. Some generated high-melting-point Cu-Ni-Fe and Ni-Fe alloys were converted to a Cu-Ni alloy with a low melting point in presence of Co from the copper refining slag, simultaneously with which the Fe was transferred out from Cu-Ni-Fe and Ni-Fe alloys and combined with Co to form a Fe-Co alloy. It increased Cu-Ni alloy droplets aggregation from molten slag and decreased their contents in the residual slag. Under optimized conditions, the Cu and Ni contents in the residual slag decreased to 0.37 and 0.06 wt%, respectively. Besides, the residual slag mainly composed of CaO, CaF2 and SiO2 could be used to prepare building materials rendering it harmless.
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Affiliation(s)
- Yang Xiao
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China
| | - Lei Li
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
| | - Manhong Huang
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China
| | - Yanbiao Liu
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China
| | - Jingzhuang Xu
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China
| | - Zhipeng Xu
- College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China
| | - Yun Lei
- Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, PR China
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11
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Improvement of Ecological Risk Considering Heavy Metal in Soil and Groundwater Surrounding Electroplating Factories. Processes (Basel) 2022. [DOI: 10.3390/pr10071267] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Heavy metals in groundwater and soil are toxic to humans. An accurate risk assessment of heavy metal contamination can aid in environmental security decision making. In this study, the improved ecological risk index (RI) is used to comprehensively investigate the influence of heavy metals in soil and groundwater within electroplating factories and their surrounding regions. In the non-overlapping area, the RI of soil and groundwater is computed individually, and in the overlapping area, the greater RI of soil and groundwater is employed. Two typical electroplating factories are used to examine the heavy metal distribution pattern. The heavy metal concentrations are compared between Factory A, which is in operation, and Factory B, which is no longer in operation, in order to analyze the heavy metal concentrations and associated ecological risks. Heavy metals continue to spread horizontally and vertically after Factory B was closed. Heavy metal concentrations in groundwater surrounding Factory B are substantially greater, and the maximum concentration exists deeper than in Factory A. Because Cr, Cu, and Hg in soil contribute significantly to the RI, the primary high RI region is observed at Factory A and the region to the southwest. The RI of Factory B demonstrates a broad, moderate risk zone in the west and southwest.
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