A heat-assisted mechanical method for back EVA recovery from end of life c-Si modules

This study introduces a novel, heat-assisted mechanical method for the sustainable separation and recovery of the back ethylene vinyl acetate (EVA) from end-of-life silicon-based photovoltaic (PV) modules. Conventional EVA separation techniques, primarily chemical dissolution and thermal treatment, suffer from limited efficacy and substantial environmental hazards. In contrast in the proposed approach, the EVA adhesive is softened by controlled heat so that it can be detached from the PV module structure with gentle mechanical force. The results show that the developed process is effective. In less than 1 min, the EVA layer was separated and recovered with a success rate of over 99 % without damaging the integrity of the recovered EVA and adjacent cells. The used analytical characterization through FTIR, TGA, XRD, and SEM-EDS further confirms the structural and chemical integrity of the recovered materials. Additionally, the method enables direct recovery of valuable copper ribbons at 50 % of the panel’s copper content, and facilitates the subsequent release of clean glass and silicon components after a short heat treatment at 400 °C, a significant improvement over existing techniques. The significance of this process lies in the following two advantages: environmentally, it reduces pollution by preventing the depletion of polymer materials and the release of hazardous gases during polymer degradation; economically, it opens up the possibility of reusing EVA polymer components, recovering intact solar cells, glass and copper ribbons, which improves the sustainability of both solar cell production and recycling processes.