Thermochemical upcycling of plastic waste: A comprehensive view from technology to commercialization

Abstract

Thermochemical upcycling has emerged as a promising industrial pathway for selectively converting waste plastics into high-value fuels, monomers, hydrogen, and carbon nanotubes, with some processes already achieving commercial deployment beyond the laboratory scale. However, a comprehensive review synthesizing recent advances in catalyst design, reactor engineering, and mechanistic insights into key thermochemical pathways remains critically lacking. To address this gap, this study aims to expedite the commercialization of thermochemical upcycling. It supports this objective by highlighting global industrial trends, emphasizing how major industrial leaders (like BASF, Dow, LG Chem, and SABIC) are pursuing their circular economy goals. Relevant policy landscapes, including carbon taxes and emissions trading, are discussed in relation to process viability. Various reactor configurations are also compared for product yield, energy efficiency, and heat integration, along with mechanistic insights into the structure-activity relationships and catalytic surface interactions. This study quantifies carbon emissions and tax implications using a lifecycle analysis, while commercial potential is assessed via experimental and simulation data. The adoption of coupled reactor systems and their subsequent integration with renewable energy should make significant advances toward next-generation processes that can address the complexity of mixed-plastic streams. Overall, this review offers a forward-looking roadmap for realizing scalable, low-carbon thermochemical systems to address plastic waste challenges.