Recent progress of chemical looping technology for waste plastic conversion

Chemical looping technology (CLT) has emerged as a promising solution for converting waste plastics into valuable heat, syngas and H2 while enabling efficient carbon capture. This technology divides chemical reactions into multiple steps, sequentially in one reactor or simultaneously in independent reactors, offering enhanced control and efficiency. This article comprehensively reviews various CLT, including chemical looping combustion, chemical looping gasification, chemical looping reforming, chemical looping hydrogen generation and their derivative technologies, with a focus on their unique advantages for value-added applications in waste plastics. These processes demonstrate high efficiency in syngas production, CO2 capture and H2 generation while maintaining low energy consumption. As the cornerstone in CLT, oxygen carriers have evolved from monometallic oxides to polymetallic oxides designs, leveraging synergistic effects to enhance resistance to carbon deposition and sintering, improve pollutant removal capabilities (such as chlorine capture) and ensure long-term cycling stability. While CLT of waste plastics shows great potential at the laboratory scale, pilot-scale studies remain limited and require further focused attention. As a key pathway for waste plastic valorization and carbon neutrality, CLT not only offers an innovative solution for global plastic pollution management but also drives the deep integration of circular economy principles with clean energy technologies, providing important new avenues for green sustainable development.