Fundamental, Technical and Environmental Overviews of Plastic Chemical Recycling

Abstract

The accumulation of plastic waste is a severe environmental challenge worldwide. Although mechanical recycling methods are in place for plastics such as polyethylene terephthalate (PET), the physical and chemical properties are significantly compromised after a number of cycles, and eventually reach end-of-life and end up in landfill. Chemical recycling is a collection of emerging innovative technologies that transform plastic waste into base chemicals, monomers and feedstocks. This approach complements mechanical recycling, bridging the gap between waste management and the petrochemical industry. However, regards to the seven types of recyclable plastics, there is currently no clear overview of the suitable techniques. Therefore, we aim to provide a critical perspective of the suitability of different chemical processes towards recycling different types of plastics, by combining fundamental knowledge and research advancements in recent years, with an emphasis on assessing their environmental and economic impacts. Finally, based on the development status, we will highlight the current challenges and future opportunities on implementing chemical recycling technologies to meet the sustainability requirement of a climate neutral circular economy.