Tag Archives: recycling

1339-1350 H.K. Trivedi, A. Meshram and R. Gupta
Organic solvent selection for delamination of end-of-life silicon photovoltaic modules based on recyclability
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Organic solvent selection for delamination of end-of-life silicon photovoltaic modules based on recyclability

H.K. Trivedi¹*, A. Meshram² and R. Gupta¹³

¹Materials Science Programme, Indian Institute of Technology Kanpur, Kalyanpur, Kanpur, IN208016 Uttar Pradesh, India
²Department of Materials Science & Engineering, Indian Institute of Technology Kanpur, Kalyanpur, IN208016 Uttar Pradesh, India
³Department of Physics, Indian Institute of Technology Kanpur, Kalyanpur, Kanpur, IN208016 Uttar Pradesh, India
*Correspondence: Harishis@iitk.ac.in

Abstract:

Photovoltaic modules (PVMs) are already accepted as renewable energy sources to fulfill future energy demand. E-waste from end-of-life (EoL) PVMs will pose significant challenges for both the recovery of valuable materials and the environmental hazards in the near future. Delamination of photovoltaic modules for recycling typically involves separating the solar cell from various layers of PVM that are; glass, encapsulant ethylene-vinyl acetate, and backsheet. The solar cell is encapsulated by ethylene-vinyl acetate (EVA) layers; the photovoltaic module can be delaminated by a swelling encapsulant layer using organic solvents.

The recyclability of organic solvents is investigated in this work, with an emphasis on possible contamination by encapsulated EVA during EoL PVM delamination. To investigate the interactions of encapsulant EVA with solvents, it was extracted from EoL PVMs. This work investigates contamination of organic solvents in the temperature range of 25–55 °C and suggests solvent recyclability for reuse and waste reduction. Organic solvents Fourier transform infrared (FTIR) spectra after a 24-hour encapsulant EVA interaction were compared to study organic solvent contamination. This study focused on two different types of solvents: aromatic hydrocarbons (like xylene) and chlorinated hydrocarbons (like CH₂Cl₂). Xylene demonstrated resistance to EVA contamination, making it a preferred organic solvent for recycling EoL PVMs.

Key words:

e-waste, ethylene-vinyl acetate (EVA), organic solvent, photovoltaic modules, recycling, solar cell

1297-1311 A. Srivastava and A. Meshram
Valorization of aluminium dross for the developmentof al-rich product
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Valorization of aluminium dross for the developmentof al-rich product

A. Srivastava* and A. Meshram

Indian Institute of Technology Kanpur, Department of Materials Science and Engineering, IN208016 Kalyanpur, India
*Correspondence: ankurs21@iitk.ac.in

Abstract:

In this study, aluminium dross undergoes a hydrometallurgical recycling process. Various chemical reagents are employed to treat the aluminium dross, facilitating the maximum extraction of aluminium content from the dross into leach liquor. The hydrometallurgical route ensures efficient aluminium leaching, forming a solution rich in Al, used as a precursor/raw material for valuable material generation.

α-alumina is obtained by leaching dross with alkalis at 323 K for 3 h and precipitating with acids followed by a calcination process at 1,473 K for 3 h. The parameters are optimized and multiple trials are done to ensure the reproducibility of the results. Morphological and topographical studies of the synthesized products are done by XRD and SEM-EDS characterizations. TGA analysis of the samples were also conducted. This work enables to recycling of aluminium dross and converts it into a valuable product which has high demand in refractory and high-temperature applications. By converting aluminium dross into a resource with intrinsic value, this process significantly mitigates environmental impact, aligning seamlessly with the principles of a sustainable and circular economy. In doing so, it exemplifies a proactive approach towards resource conservation, waste reduction, and the responsible utilization of materials within industrial processes.

Key words:

aluminium dross, hydrometallurgy, recovery, recycling, valuable product

1199–1206 K.K. Singh, A. Meshram, D. Gautam and A. Jain
Hydrogen production using waste aluminium dross: from industrial waste to next-generation fuel
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Hydrogen production using waste aluminium dross: from industrial waste to next-generation fuel

K.K. Singh*, A. Meshram, D. Gautam and A. Jain

Indian Institute of Technology, Banaras Hindu University, Department of Metallurgical Engineering, IN221005 Varanasi India
*Correspondence: kksingh.met@iitbhu.ac.in

Abstract:

This article describes the production of hydrogen from white aluminium dross, an industrial waste generated in the aluminium smelter plants. Hydrogen is generated by metal-water reaction between aluminium and water in presence of alkalis like sodium hydroxide and potassium hydroxide. Aluminium dross is described as a heterogeneous material with its major constituents being metallic aluminium, alumina and other salt fluxes like NaCl and KCl. Utilizing the metallic aluminium content entrapped in the matrix of alumina for the metal-water reaction has been the driving force for the waste recycling and simultaneous hydrogen production. Bulk aluminium dross was crushed and downsized. The finer fraction of the powdered aluminium dross is used for the experiments. The effects of dross in the alkaline solution, temperature of the solution and the time of the reaction were studied to understand the generation of hydrogen. The alkaline solution breaks the protective layer of alumina and exposes the entrapped aluminium content to water, thereby commencing the hydrogen liberation.

Key words:

aluminium dross, Hydrogen, recycling, waste management

1257-1265 M. Tichý, M. Müller, P. Valášek and I. Miturska
Effect of rubber powder from waste tyre rubbers on mechanical properties of one-component polyurethane putty
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Effect of rubber powder from waste tyre rubbers on mechanical properties of one-component polyurethane putty

M. Tichý¹*, M. Müller¹, P. Valášek¹ and I. Miturska²

¹Czech University of Life Sciences, Faculty of Engineering, Department of Material Science and Manufacturing Technology, Faculty of Engineering, Kamýcká 129, CZ165 21 Prague, Czech Republic
²Lublin University of Technology, Department of Production Engineering, Mechanical Engineering Faculty, Nadbystrzycka 36, PL20 618 Lublin, Poland
*Correspondence: xticm001@studenti.czu.cz

Abstract:

The utilization of adhesives in technical practice is varied. Adhesives serve for a creation of strength bonds on the one hand, and on the other hand e.g. for cementing. The aim of the research is a modification of one-component polyurethane putty RPS 45 used in automotive industry to increase strength properties in an adhesive bond. An interaction between a filler in the form of rubber powder micro-particles and one-component polyurethane adhesive was investigated by means of SEM analysis. Sealing is a primary property of this putty. Sealing putties usually reach very small strength which can be increased by an admixture of the filler. In order to keep elastic properties, micro-particles of the rubber powder gained from tyre recycling process were used as the filler. An aspect of a loading speed of the adhesive bond is essential at the practical application at which the adhesive bond can be failed in adhesive or cohesive layers. The adhesive bond can be perceived in terms of its function as a complex of three layers, i.e. an adhesive bonded material, the interaction between the adhesive and the adhesive bonded material and the adhesive layer itself. There are often states in the practices when the adhesive bonds are exposed to the loading which can be either a static or a dynamic one. That is why the research is focused not only on the evaluation of the influence of the modification of the one-component polyurethane adhesive, but also on the influence of the loading speed of the adhesive bond. Tested speeds set on a universal testing machine Zwick/Roell Z150 were 2, 50 and 100 mm min^-1. The results of mechanical tests proved a positive influence of the filler on the strength σ_m higher by 42.68 ± 6.96% and the elongation at break ε_b higher by 12.2 ± 20.95%. On the contrary, the stress at yield σ_y was decreased.

Key words:

elongation, Loading speed, particle filler, recycling, SEM, strength, stress at yield