Chemical Recycling of Plastic Waste: Current Approaches and Future Prospects

Abstract

Chemical recycling refers to processes that transform plastic waste into chemical
feedstocks, monomers, oligomers, fuels, or other useful products through chemical or
thermochemical reactions. It is being investigated as a complement to mechanical
recycling, particularly for mixed, contaminated, multilayer, or chemically complex
plastic waste that is difficult to process mechanically. Major approaches include
pyrolysis, gasification, depolymerization, solvolysis, hydrolysis, glycolysis,
methanolysis, and selective dissolution. The suitability and environmental performance
of each method depend strongly on polymer chemistry, feedstock quality, energy
requirements, product yields, emissions, and the availability of markets for recovered
products. This paper examines nine major dimensions of chemical recycling, including
polymer feedstocks, current technologies, process chemistry, product recovery,
integration with mechanical recycling, environmental assessment, industrial challenges,
policy considerations, and future prospects.