Environmental assessment of the recycling process for polyamides-Polyethylene multilayer packaging films

The plastic packaging, and in particular the multilayer flexible packaging, has several characteristics that make it essential in everyday life. However, the sustainability of used materials is undermined by the difficulties encountered for their recycling. The purpose of this study is to assess both the technical feasibility, and above all the environmental sustainability of an effective process enabling the recycling of polyamides-polyethylene multilayers packaging films. The technique used for the separation of the polymers is based on a selective dissolution, carried out using monoethylene glycol. The experimental tests made possible to identify the best conditions for treating the films and for maximizing yields and final products quality. The Life Cycle Assessment of the recycling process modelled at an industrial level, firstly allowed to determine the main process hotspots (i. e. the energy consumption). The LCA analysis was then extended, examining the life cycle of polyamidespolyethylene films with different end-of-life treatments, i.e. incineration, energy recovery and recycling. The results showed that the recycling process, carried out through the selective dissolution of the films, allows to reduce the overall environmental impacts of these materials along their life cycle. Therefore the recycling process analysed here can be considered an effective approach to increase environmental sustainability and recovery of raw materials.