Estudo da solubilização do EVA em células fotovoltaicas usando solventes com baixa toxicidade e baixo impacto ambiental

Abstract

The use of solar energy through photovoltaic panels is becoming increasingly widespread due to its high efficiency and non-emission of pollutants, making it the best option for replacing fossil fuels. Photovoltaic panels are composed by layers of different types of materials (glass, metals and polymers) and the separation and reuse of all these components is challenging. Ethylene vinyl acetate (EVA) copolymer is typically the polymer used as an encapsulant between the layers, and during the panel recycling process, incineration or the use of highly toxic solvents such as toluene and xylene are the most common ways of removing the polymer. In this study, solvents from natural sources, such as fruits and essential oils, were used to perform the solubilization of EVA in order to reduce the environmental impact due to their low toxicity. The thermal solubilization method was the most used during the work, sometimes associated with the ultrasonic process or UV radiation. Different concentrations of the solvents were tested in contact with the polymer, both in pellet form and in powder form extracted from real photovoltaic panels. To determine the efficiency of the process, FTIR-ATR was the most used characterization method. At the end of the study, it was possible to observe that the developed method enables the recovery of EVA in a sustainable and clean way, using green solvents.