Catalysts for Tar Reforming in Biomass and Solid Waste Gasification: A Comprehensive Review

Catalytic reforming plays a pivotal role in converting tar produced from the gasification of biomass and municipal solid waste (MSW). This review offers an in-depth discussion of formation processes and major components of tar, as well as the fundamental mechanisms of its catalytic reforming. The review also introduced various catalysts and their deactivation issues, such as active metals (transition metals, noble metals, and alkali metals), supports (metal oxides, carbon-based materials, perovskites, and core-shell structures), and promoters. Meanwhile, it summarized the synergistic interactions between active metals and supports, along with the modulation of catalyst redox properties, metal-support interactions (MSI), and surface acidity/basicity through promoters. Furthermore, the main challenges at industrial scale are summarized: complex chemistry, particle clogging and thermal stress. Current strategies being explored to address these include structured and alloyed catalysts, process integration, catalyst regeneration and simulation optimization. It was expected to further flourish the catalytic reforming in the energy regeneration of biomass and solid waste gasification.