Recycling of multilayer packaging waste with sustainable solvents

De-pulped multilayer packaging waste containing low-density polyethylene (LDPE) and aluminium was separated into its single components by using sustainable solvents capable of solubilizing LDPE under mild conditions. LDPE and aluminium of high purity and quality were recovered with biodiesel, 2-methyl tetrahydrofuran (2-MeTHF) and cyclopentyl methyl ether (CPME). The recovered LDPE has been characterized by thermal and mechanical analysis, confirming its similarity to the polymer before the dissolution process, while the recovered aluminium was analysed by X-Ray Photoelectron Spectroscopy (XPS) depth profiling, confirming the nonoxidative behaviour of the tested solvents. The mass balance of the recovered materials and solvents at the end of the dissolution process was close to 100%.