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Javaid S, Zanoletti A, Serpe A, Bontempi E, Alessandri I, Vassalini I. Glassy Powder Derived from Waste Printed Circuit Boards for Methylene Blue Adsorption. Molecules 2024; 29:400. [PMID: 38257313 PMCID: PMC10821274 DOI: 10.3390/molecules29020400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 01/10/2024] [Accepted: 01/11/2024] [Indexed: 01/24/2024] Open
Abstract
Electronic waste (e-waste) is one of the fastest-growing waste streams in the world and Europe is classified as the first producer in terms of per capita amount. To reduce the environmental impact of e-waste, it is important to recycle it. This work shows the possibility of reusing glassy substrates, derived from the MW-assisted acidic leaching of Waste Printed Circuit Boards (WPCBs), as an adsorbent material. The results revealed an excellent adsorption capability against methylene blue (MB; aqueous solutions in the concentration range 10-5 M-2 × 10-5 M, at pH = 7.5). Comparisons were performed with reference samples such as activated carbons (ACs), the adsorbent mostly used at the industrial level; untreated PCB samples; and ground glass slides. The obtained results show that MW-treated WPCB powder outperformed both ground glass and ground untreated PCBs in MB adsorption, almost matching AC adsorption. The use of this new adsorbent obtained through the valorization of e-waste offers advantages not only in terms of cost but also in terms of environmental sustainability.
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Affiliation(s)
- Saad Javaid
- Sustainable Chemistry and Materials Laboratory, Department of Information Engineering, University of Brescia, Via Branze 38, 25123 Brescia, Italy; (S.J.); (I.A.)
| | - Alessandra Zanoletti
- Chemistry for Technologies Laboratory, Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze 38, 25123 Brescia, Italy;
- Unit of National Interuniversity Consortium for Materials Science and Technology (INSTM), Research Unit of Brescia, Via Branze 38, 25123 Brescia, Italy
| | - Angela Serpe
- Department of Civil and Environmental Engineering and Architecture (DICAAR), INSTM Unit, Via Marengo 2, 09123 Cagliari, Italy;
- National Research Council of Italy, Institute of Environmental Geology and Geoengineering (CNR-IGAG), Via Marengo 2, 09123 Cagliari, Italy
| | - Elza Bontempi
- Chemistry for Technologies Laboratory, Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze 38, 25123 Brescia, Italy;
- Unit of National Interuniversity Consortium for Materials Science and Technology (INSTM), Research Unit of Brescia, Via Branze 38, 25123 Brescia, Italy
| | - Ivano Alessandri
- Sustainable Chemistry and Materials Laboratory, Department of Information Engineering, University of Brescia, Via Branze 38, 25123 Brescia, Italy; (S.J.); (I.A.)
- Unit of National Interuniversity Consortium for Materials Science and Technology (INSTM), Research Unit of Brescia, Via Branze 38, 25123 Brescia, Italy
- CNR-INO (National Research Council-National Institute of Optics), Research Unit of Brescia, Via Branze 38, 25123 Brescia, Italy
| | - Irene Vassalini
- Sustainable Chemistry and Materials Laboratory, Department of Information Engineering, University of Brescia, Via Branze 38, 25123 Brescia, Italy; (S.J.); (I.A.)
- Unit of National Interuniversity Consortium for Materials Science and Technology (INSTM), Research Unit of Brescia, Via Branze 38, 25123 Brescia, Italy
- CNR-INO (National Research Council-National Institute of Optics), Research Unit of Brescia, Via Branze 38, 25123 Brescia, Italy
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Tuncuk A. Lab scale optimization and two-step sequential bench scale reactor leaching tests for the chemical dissolution of Cu, Au & Ag from waste electrical and electronic equipment (WEEE). WASTE MANAGEMENT (NEW YORK, N.Y.) 2019; 95:636-643. [PMID: 31351651 DOI: 10.1016/j.wasman.2019.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 07/03/2019] [Accepted: 07/04/2019] [Indexed: 06/10/2023]
Abstract
Regulations force to Waste Electrical and Electronic Equipment (WEEE) management by recycling the materials by safe and suitable methods, due to generating massive amounts of WEEE. This research aims towards extract metals from waste random-access memory (RAM) devices in different solutions. In addition, the effect of different parameters such as reagent concentration, oxidant concentration and solid/liquid ratio were investigated with full factorial experimental design tests and analysis of variance (ANOVA). The results showed that the extraction of gold and silver was 96.81% and 99.02% respectively under the following conditions: concentration of 2% iodine and 3% hydrogen peroxide as oxidizing agent, 5% solid/liquid ratio and leaching period of 2 h. An increase of the hydrogen peroxide concentration increased gold and silver extraction. While about 79.30% silver was found to be extracted using 2 M sulfuric acid, 1.5 M ammonium persulfate, 5% solid/liquid ratio and leaching period of 5 h, 79.43% copper was extracted by using ammonia instead of sulfuric acid under the same conditions. Ammonium persulfate was found to be a good oxidizing agent for sulfuric acid and ammonia leaching, since it provided selective extraction of silver and copper respectively. Two-step sequential bench scale reactor leaching tests were conducted to extract copper (98.73%), gold (99.98%) and silver (96.90%) selectively with high extraction. Two-step leaching approach was concluded as the most appropriate method for selective extraction of targeted metals from waste RAM devices.
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Affiliation(s)
- Aysenur Tuncuk
- Mineral-Metal Recovery and Recycling (MMR&R) Research Group, Mineral Processing Division, Department of Mining Engineering, Suleyman Demirel University, TR32260 Isparta, Turkey.
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