A Panoramic View on Plastic Waste Recycling and Upcycling: Heterogeneous Catalytic Strategies for Diverse Plastics and Multiple Pathways

Plastics have become integral to modern society due to their low cost, versatility, and practicality. However, their rapid production and limited lifespan have led to the accumulation of vast plastic waste, posing severe threats to public health, the environment, and ecological balance. Heterogeneous catalysis has emerged as a key strategy for the value-added recycling of plastic waste due to its high efficiency and low separation costs. This review systematically summarizes recent advancements in heterogeneous catalytic strategies for converting waste plastics into high-value chemicals and functional materials. It provides a detailed classification of commercial plastics and their applications while analyzing key efficiency metrics for plastic upcycling. Various heterogeneous catalytic approaches, including thermal catalysis, photocatalysis, electrocatalysis, photothermal catalysis, photoelectrocatalysis, joule heating, microwave-assisted catalysis, and ball milling are explored in terms of transformation strategies, resource utilization, and catalytic mechanisms. Additionally, the review examines fundamental reaction pathways, such as C─H bond activation and C─C/C─O bond cleavage. Finally, based on current research and theoretical insights, future directions for heterogeneous catalytic plastic upcycling are discussed, including catalyst development, degradable polymer synthesis, mechanistic investigations, and commercial viability assessments. This review aims to provide new perspectives on addressing plastic pollution through advanced catalytic technologies.