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Chetima A, Nde Bup D, Kewir F, Wahaboua A. Activated carbons from open air and microwave-assisted impregnation of cotton and neem husks efficiently decolorize neutral cotton oil. Heliyon 2024; 10:e24060. [PMID: 38283249 PMCID: PMC10818195 DOI: 10.1016/j.heliyon.2024.e24060] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 12/06/2023] [Accepted: 01/03/2024] [Indexed: 01/30/2024] Open
Abstract
The decolorization of cottonseed oil with activated carbons (ACs) from neem and cotton husks has a dual interest: elimination of undesirable pigments in oil and valorization of the husks; by-products of neem and cottonseed processing, which would otherwise be dumped along riverbanks and farms causing environmental pollution. ACs were produced from neem and cottonseed husks after acid impregnation assisted by microwave heating and in ambient air for the decolorization of neutral cottonseed oil. The experimental data were analyzed by the intraparticle diffusion and the pseudo-second-order kinetic models as well as the Langmuir and Freundlich isotherm models. The method of impregnation and carbonization time had dramatic effects on the specific surface area (800-1500 g/m2), the quantity of burn-off (50-70 %), and methylene blue index (300-5000 mg/g) values which indicated the potential of the prepared activated carbons in the bleaching of vegetable oil and in other applications such as environmental clean-up and in agriculture. Pigment adsorption increased with temperature for all ACs indicating that the decolorization process was endothermic. The quantity of adsorbent equally had a significant effect on the pigment adsorption process for all ACs. All the activated carbons prepared in this work were 30-80 % more efficient in pigment adsorption than bleaching earth that is normally used in decolorizing neutral cotton seed oil in industries. All tested models are adequate to describe pigment adsorption by the ACs. Both methods of preparation of ACs were effective for oil decolorization, but microwave impregnation is more appealing because it requires only 1 h compared to 6 h for ambient air. Optimum decolorization conditions were 90 °C for 40min and adsorbent concentration of 2 %.
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Affiliation(s)
- Abba Chetima
- Department of Inorganic Chemistry, Faculty of Science, University of Maroua, Cameroon
| | - Divine Nde Bup
- Department of Nutrition Food and Bio-resource Technology, College of Technology, University of Bamenda, Cameroon
| | - Fannyuy Kewir
- Department of Nutrition Food and Bio-resource Technology, College of Technology, University of Bamenda, Cameroon
| | - Abdoul Wahaboua
- Department of Inorganic Chemistry, Faculty of Science, University of Maroua, Cameroon
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Päivärinta-Antikainen S, Huovinen M, Ojala S, Matějová L, Keiski RL, Vähäkangas KH. Leaching of metals from red mud and toxicity in human cells in vitro. Chemosphere 2023; 332:138807. [PMID: 37121288 DOI: 10.1016/j.chemosphere.2023.138807] [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: 12/29/2022] [Revised: 04/26/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023]
Abstract
Toxicity of red mud, a waste from alumina production, was studied using human breast cancer MCF-7 cells. Culture medium was prepared by mixing water for 3 days with the red mud and removing solid particles afterwards (red mud water). Culture for 48 h of the cells in this medium in neutral pH decreased the cell viability, as analyzed by the MTT-test, and increased the formation of reactive oxygen species. Thus, neutralization does not eliminate the toxicity of red mud. In preliminary experiments, a combined effect of five metals (Cr, Li, V, Al, As) increased the formation of ROS (reactive oxygen species) statistically significantly. Each element separately did not have a similar effect. In environmental applications, red mud is likely to be used after activation. In this work, the red mud was activated using hydrochloric acid to study the physical and chemical properties before and after the treatment. Activation increased the specific surface area of red mud from 16 m2 g-1 to 148 m2 g-1, which is beneficial in many environmental applications such as in the adsorptive removal of pollutants. After activation, leaching of some elements from the red mud decreased (e.g. Al from 38.0 to 0.56 mg L-1, As from 21.0 to 2.1 μg L-1, V from 172.0 to 29.8 μg L-1) while some increased (e.g. Li from 0.04 to 2.81 mg L-1, Cr from 0.35 to 3.23 mg L-1).
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Affiliation(s)
| | - Marjo Huovinen
- School of Pharmacy/Toxicology, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Satu Ojala
- Environmental and Chemical Engineering, Faculty of Technology, University of Oulu, Oulu, Finland
| | - Lenka Matějová
- Institute of Environmental Technology, CEET, VŠB-Technical University of Ostrava, Ostrava, Czech Republic
| | - Riitta L Keiski
- Environmental and Chemical Engineering, Faculty of Technology, University of Oulu, Oulu, Finland
| | - Kirsi H Vähäkangas
- School of Pharmacy/Toxicology, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
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Zhu Z, Huang Y, Yu M, Cheng H, Li Z, Xu W. Improved adsorption capacity and applicable temperature of gaseous PbCl 2 capture by modified montmorillonite with combined thermal treatment and acid activation. Chemosphere 2023; 313:137466. [PMID: 36481175 DOI: 10.1016/j.chemosphere.2022.137466] [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: 08/30/2022] [Revised: 12/01/2022] [Accepted: 12/02/2022] [Indexed: 06/17/2023]
Abstract
The emission of semi-volatile heavy metals during the thermal utilization of various fuels has been a huge threat to the environment. In this study, the montmorillonite modified by thermal treatment and hydrochloric acid activation was evaluated for the PbCl2 adsorption performance. The optimum adsorption temperature of sorbents increased with the thermal treatment temperature (<500 °C) for the increased amount of reactive sites caused by the removal of interlayer water and hydroxyl, while a higher treatment temperature will collapse the lamellar structure of montmorillonite and greatly inhibit the PbCl2 adsorption. Besides, the hydrochloric acid activation can help inhibit the melting of sorbents during the adsorption process by removing the impurities and promote the PbCl2 vapor to contact with more reactive sites at higher temperatures. By comparing different sorbents, montmorillonite was found to exhibit better adsorption performance at 600-700 °C, while the sorbent thermal-treated at 500 °C and then acid-activated got the highest adsorption efficiency at 900 °C, which was 17.83% higher than that of montmorillonite. This study provided an environmental-friendly modification method to capture more heavy metals at high-temperature conditions, which can be partly realized by the recycling of montmorillonite used for the removal of normal gas pollutants in lower temperatures conditions or acid wastewater treatment.
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Affiliation(s)
- Zhicheng Zhu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China
| | - Yaji Huang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China.
| | - Mengzhu Yu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China
| | - Haoqiang Cheng
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China
| | - Zhiyuan Li
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China
| | - Wentao Xu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China
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Ahmad S, Imran M, Amin M, Al-Kahtani AA, Arshad M, Nawaz R, Shah NS, Schotting RJ. Potential of magnetic quinoa biosorbent composite and HNO 3 treated biosorbent for effective sequestration of chromium (VI) from contaminated water. Int J Phytoremediation 2023; 25:929-939. [PMID: 36121769 DOI: 10.1080/15226514.2022.2122926] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The present study aims to prepare novel quinoa biosorbent (QB), acid activated QB (QB/Acid) and its nanocomposite with magnetic nanoparticles (QB/MNPs) for batch scale Cr removal from contaminated water. The Cr adsorption was systematically studied at different pH (2-9), adsorbent dosage (1-3 g/L), initial concentration (25-200 mg/L), contact time (180 min) and competing ions in water. Maximum Cr adsorption was observed onto QB/MNPs (57.4 mg/L), followed by QB/Acid (46.35 mg/g) and QB (39.9 mg/g). The Cr removal by QB/MNPs was higher than QB/Acid and QB. Results revealed that the highest Cr removal was obtained at optimum pH 4, 25 mg/L, and 2 g/L dosage. The FTIR spectra displayed various functional groups on adsorbents surface serving as a potential scaffold to remove Cr from contaminated water. The equilibrium and kinetic Cr adsorption data best fitted with Freundlich and pseudo-second order models, respectively (R2 ≥ 0.96). The QB/MNPs showed excellent reusability in five adsorption/desorption cycles (4.7% decline) with minor leaching of Fe (below threshold level). The coexisting ions in groundwater showed an inhibitory effect on Cr sequestration (5%) from water. The comparison of Cr adsorption by QB/MNPs and QB/Acid showed better potential for Cr sequestration than various previously explored adsorbents in the literature.
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Affiliation(s)
- Sajjad Ahmad
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari, Pakistan
| | - Muhammad Imran
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari, Pakistan
| | - Maryam Amin
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari, Pakistan
| | - Abdullah A Al-Kahtani
- Department of Chemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Muhammad Arshad
- Department of Agriculture and Food Technology, Karakoram International University, Gilgit, Pakistan
| | - Rab Nawaz
- Department of Environmental Sciences, University of Lahore, Lahore, Pakistan
| | - Noor Samad Shah
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari, Pakistan
| | - Ruud J Schotting
- Environmental Hydrogeology Research Group, Department of Earth Sciences, Utrecht University, Utrecht, The Netherlands
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Wang M, Bera G, Mitra K, Wade TL, Knap AH, Phillips TD. Tight sorption of arsenic, cadmium, mercury, and lead by edible activated carbon and acid-processed montmorillonite clay. Environ Sci Pollut Res Int 2021; 28:6758-6770. [PMID: 33009611 PMCID: PMC7855320 DOI: 10.1007/s11356-020-10973-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 09/21/2020] [Indexed: 05/21/2023]
Abstract
Heavy metal exposure in humans and animals commonly occurs through the consumption of metal-contaminated drinking water and food. Although many studies have focused on the remediation of metals by purification of water using sorbents, limited therapeutic sorbent strategies have been developed to minimize human and animal exposures to contaminated water and food. To address this need, a medical grade activated carbon (MAC) and an acid processed montmorillonite clay (APM) were characterized for their ability to bind heavy metals and mixtures. Results of screening and adsorption/desorption isotherms showed that binding plots for arsenic, cadmium, and mercury sorption on surfaces of MAC (and lead on APM) fit the Langmuir model. The highest binding percentage, capacity, and affinity were shown in a simulated stomach model, and the lowest percentage desorption (< 18%) was shown in a simulated intestine model. The safety and protective ability of MAC and APM were confirmed in a living organism (Hydra vulgaris) where 0.1% MAC significantly protected the hydra against As, Cd, Hg, and a mixture of metals by 30-70%. In other studies, APM showed significant reduction (75%) of Pd toxicity, compared with MAC and heat-collapsed APM, suggesting that the interlayer of APM was important for Pb sorption. This is the first report showing that edible sorbents can bind mixtures of heavy metals in a simulated gastrointestinal tract and prevent their toxicity in a living organism. Graphical abstract.
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Affiliation(s)
- Meichen Wang
- Veterinary Integrative Biosciences Department, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843, USA
| | - Gopal Bera
- Geochemical & Environmental Research Group, Texas A&M University, College Station, TX, 77845, USA
| | - Kusumica Mitra
- Geochemical & Environmental Research Group, Texas A&M University, College Station, TX, 77845, USA
| | - Terry L Wade
- Geochemical & Environmental Research Group, Texas A&M University, College Station, TX, 77845, USA
| | - Anthony H Knap
- Geochemical & Environmental Research Group, Texas A&M University, College Station, TX, 77845, USA
| | - Timothy D Phillips
- Veterinary Integrative Biosciences Department, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843, USA.
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Pawar RR, Lalhmunsiama, Ingole PG, Lee SM. Use of activated bentonite-alginate composite beads for efficient removal of toxic Cu 2+ and Pb 2+ ions from aquatic environment. Int J Biol Macromol 2020; 164:3145-54. [PMID: 32827615 DOI: 10.1016/j.ijbiomac.2020.08.130] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 08/07/2020] [Accepted: 08/16/2020] [Indexed: 12/18/2022]
Abstract
The toxic heavy metals contamination in water bodies is one of the major concerns in many countries. Copper and lead are the two common toxic metals present in aquatic environments due to their extensive usage in various industries for diverse applications. The present study deals with the removal of these two toxic heavy metal ions using activated bentonite-alginate (ABn-AG) composite beads which are easily separated and recovered after adsorption reaction. Composite beads were prepared by adapting the ionic gelation method and the materials; i.e., raw bentonite (BnR), activated bentonite (ABn) and ABn-AG were characterized by XRD, BET surface area, TGA-DTA, FT-IR, SEM analyses. The nitrogen adsorption-desorption isotherm obtained for the materials were the type IV isotherm with characteristics H3 hysteresis loops indicating the presence of mesopores with slit-shaped pores. Batch experiments showed that reasonably high percent removal was achieved even at highly acidic conditions, i.e., 58% of Cu2+and 77% of Pb2+were removed at pH 2.0. The removal was fast during the initial contact time and the adsorption data obtained at various contact time were fit well to the pseudo-second order kinetic model. The maximum sorption capacity for Cu2+ was found to be 17.30 mg/g whereas Pb2+ was found to be 107.52 mg/g. The presence of MgCl2, NaCl and KCl did not cause significant influence on the removal of Cu2+ and Pb2+ using ABn-AG. Binary adsorption study suggested that Cu2+ and Pb2+ were removed through different binding sites present in ABn-AG. Reusability test showed that removal of Cu2+ and Pb2+ decreased by 10% only after the same material was reused for 5 times indicating that ABn-AG is a highly robust material and can be reuse for several times without losing its efficiency. Thus, this study suggested that ABn-AG composite beads can be employed as an efficient adsorbent for the removal of Cu2+ and Pb2+ from aqueous waste.
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Ndé HS, Tamfuh PA, Clet G, Vieillard J, Mbognou MT, Woumfo ED. Comparison of HCl and H 2SO 4 for the acid activation of a cameroonian smectite soil clay: palm oil discolouration and landfill leachate treatment. Heliyon 2020; 5:e02926. [PMID: 31890940 PMCID: PMC6926220 DOI: 10.1016/j.heliyon.2019.e02926] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 11/01/2019] [Accepted: 11/22/2019] [Indexed: 11/18/2022] Open
Abstract
Vertisols occupy approximately 1,200,000 ha in Northern Cameroon. Their richness in smectites allows for the production of “bleaching earths” necessary for refining palm oil, and their effluent is used for leachate treatment. In the present work, two mineral acids (HCl and H2SO4) were compared, and the most efficient acid with the lowest cost was determined for use in industrial applications. Under similar experimental conditions (ratio of acid solution/clay mass = 5/1, temperature = 97 °C, stirring time = 4 h), the quantity of cations (Fe2+, Fe3+, Al3+) solubilised during acid activation, palm oil discolouration rate by each activated sample and the financial cost of 5 L of acid solution that is required for the acid activation of one kilogram of smectite clay were compared. It was found that 2N H2SO4 was more efficient than 1N HCl and 1N H2SO4, considering palm oil bleaching efficiency and cost. The filtrate collected after the acid activation of vertisols was rich in H+ (2.04.10−1M), Fe2+ (2.8.10−3M), Fe3+ (4.2.10−2M) and Al3+ (9.2.10−2M) ions. One gram of smectite clay material produced 9 mL of this filtrate that was used for the treatment of leachate from a controlled landfill. The leachate colour decreased from 4262 to 285 PtCo units, while the corresponding chemical oxygen demand (COD) decreased from 802 to 128 mg/L. Thus, the most effective acid for industrial bleaching earth production from vertisol is 2N H2SO4 acid.
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Affiliation(s)
- H Soh Ndé
- Department of Inorganic Chemistry, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon
| | - P Azinwi Tamfuh
- Department of Soil Science, Faculty of Agronomy and Agricultural Sciences, University of Dschang, BP 222, Dschang, Cameroon
| | - G Clet
- Normandie Univ, ENSICAEN, UNICAEN, CNRS, LCS, 14000, Caen, France
| | - J Vieillard
- Normandie Univ, UNIROUEN, INSA Rouen, CNRS, COBRA (UMR 6014), 76000, Rouen, France
| | - M Tsaffo Mbognou
- Department of Inorganic Chemistry, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.,Institut de Recherches Géologiques et Minières B.P. 4110, Yaoundé, Cameroon
| | - E Djoufac Woumfo
- Department of Inorganic Chemistry, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon
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Cao L, Yu IKM, Tsang DCW, Zhang S, Ok YS, Kwon EE, Song H, Poon CS. Phosphoric acid-activated wood biochar for catalytic conversion of starch-rich food waste into glucose and 5-hydroxymethylfurfural. Bioresour Technol 2018; 267:242-248. [PMID: 30025320 DOI: 10.1016/j.biortech.2018.07.048] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [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: 06/11/2018] [Revised: 07/08/2018] [Accepted: 07/09/2018] [Indexed: 06/08/2023]
Abstract
The catalytic activity of engineered biochar was scrutinized for generation of glucose and hydroxymethylfurfural (HMF) from starch-rich food waste (bread, rice, and spaghetti). The biochar catalysts were synthesized by chemical activation of pinewood sawdust with phosphoric acid at 400-600 °C. Higher activation temperatures enhanced the development of porosity and acidity (characterized by COPO3 and CPO3 surface groups), which imparted higher catalytic activity of H3PO4-activated biochar towards starch hydrolysis and fructose dehydration. Positive correlations were observed between HMF selectivity and ratio of mesopore to micropore volume, and between fructose conversion and total acid density. High yields of glucose (86.5 Cmol% at 150 °C, 20 min) and HMF (30.2 Cmol% at 180 °C, 20 min) were produced from rice starch and bread waste, respectively, over H3PO4-activated biochar. These results highlighted the potential of biochar catalyst in biorefinery as an emerging application of engineered biochar.
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Affiliation(s)
- Leichang Cao
- Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Iris K M Yu
- Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
| | - Shicheng Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Yong Sik Ok
- Korea Biochar Research Center, O-Jeong Eco-Resilience Institute (OJERI) & Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Eilhann E Kwon
- Department of Environment and Energy, Sejong University, Seoul 05006, Republic of Korea
| | - Hocheol Song
- Department of Environment and Energy, Sejong University, Seoul 05006, Republic of Korea
| | - Chi Sun Poon
- Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
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Potsi G, Ladavos AK, Petrakis D, Douvalis AP, Sanakis Y, Katsiotis MS, Papavassiliou G, Alhassan S, Gournis D, Rudolf P. Iron-substituted cubic silsesquioxane pillared clays: Synthesis, characterization and acid catalytic activity. J Colloid Interface Sci 2018; 510:395-406. [PMID: 28964947 DOI: 10.1016/j.jcis.2017.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 09/01/2017] [Accepted: 09/01/2017] [Indexed: 11/27/2022]
Abstract
Novel pillared structures were developed from the intercalation of iron-substituted cubic silsesquioxanes in a sodium and an acid-activated montmorillonite nanoclay and evaluated as acid catalysts. Octameric cubic oligosiloxanes were formed upon controlled hydrolytic polycondensation of the corresponding monomer (a diamino-alkoxysilane) and reacted with iron cations to form complexes that were intercalated within the layered nanoclay matrices. Upon calcination iron oxide nanoparticles are formed which are located on the silica cubes (pillars) and on the surfaces of the clay platelets. Acid activation of the nanoclay was performed in order to increase the number of acid active sites in the pristine clay and thus increase its catalytic activity. A plethora of analytical techniques including X-ray diffraction, thermal analyses, Fourier transform infrared, electron paramagnetic resonance, Raman, Mössbauer and X-ray photoelectron spectroscopies and porosimetry measurements were used in order to follow the synthesis steps and to fully characterize the final catalysts. The resulting pillared clays exhibit a high specific area and show significant acid catalytic activity that was verified using the catalytic dehydration of isopropanol asa probe reaction.
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Affiliation(s)
- Georgia Potsi
- Department of Materials Science & Engineering, University of Ioannina, 45110 Ioannina, Greece; Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
| | - Athanasios K Ladavos
- School of Natural Resources and Enterprise Management, University of Patras, Agrinio 30100, Greece.
| | - Dimitrios Petrakis
- Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece.
| | | | - Yiannis Sanakis
- Institute of Nanoscience and Nanotechnology, NCSR "DEMOKRITOS", 15310 Ag. Paraskevi-Attikis, Athens, Greece.
| | - Marios S Katsiotis
- Department of Chemical Engineering, The Petroleum Institute, PO Box 2533, Abu Dhabi, United Arab Emirates.
| | - Georgios Papavassiliou
- Institute of Nanoscience and Nanotechnology, NCSR "DEMOKRITOS", 15310 Ag. Paraskevi-Attikis, Athens, Greece.
| | - Saeed Alhassan
- Department of Chemical Engineering, The Petroleum Institute, PO Box 2533, Abu Dhabi, United Arab Emirates.
| | - Dimitrios Gournis
- Department of Materials Science & Engineering, University of Ioannina, 45110 Ioannina, Greece.
| | - Petra Rudolf
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
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Chakroun S, Herchi M, Mechti W, Gaied ME. Acid activation of upper Eocene Ca-bentonite for soybean oil clarification. Environ Sci Pollut Res Int 2017; 24:22557-22569. [PMID: 28804805 DOI: 10.1007/s11356-017-9803-x] [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: 05/11/2017] [Accepted: 07/19/2017] [Indexed: 06/07/2023]
Abstract
In central Tunisia, many upper Eocene outcrops supply smectitic claystone which are characterized by several analytical techniques (calcimetry, XRD, SediGraph, chemical analysis, surface area, etc.). Beidellite is the main mineral detected by the XRD method. Representative raw samples M1, taken from Henchir Souar (Zaghouan, Tunisia), were acid activated in order to improve their physicochemical properties. This study consists in optimizing the activation conditions with HCl 3 N by varying the following parameters: time (2, 4, and 6 h) and temperature (25, 50, 75, and 90 °C). The characterization by XRD and chemical analysis was carried out on the samples (M1, activated for 2 and 6 h at 75 °C), showing a structural modification of the clay by reduction of intensity reflection 001 order of smectite and dissolution of metal ions (Al3+, Fe3+, and Mg2+) from clay structure. Optimum condition for soybean oil clarification is obtained using a variety of amount raw clays (0.5, 0.75, and 1%). Thus, the best clarification yield is given at 0.75% of clay, showing a capacity of about 55%. Various forms of activated materials were used with a 75% proportion to leach soybean oil. Results were compared with commercial bentonite (Tonsil) having surface area (378 m2/g). The activated sample M1 during 4 h at 75 °C possesses a decolorizing capacity of about 85% greater than the oil treated by Tonsil in laboratory (58%).
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Affiliation(s)
- Salima Chakroun
- Laboratoire des Ressources Minérales et Environnement, Département des Sciences de la terre, Faculté des Sciences de Tunis, Université de Tunis El Manar, Tunis, Tunisie.
| | - Mongi Herchi
- Laboratoire des Ressources Minérales et Environnement, Département des Sciences de la terre, Faculté des Sciences de Tunis, Université de Tunis El Manar, Tunis, Tunisie
| | - Wafa Mechti
- Laboratoire des Ressources Minérales et Environnement, Département des Sciences de la terre, Faculté des Sciences de Tunis, Université de Tunis El Manar, Tunis, Tunisie
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