Biomass pyrolysis mechanism for carbon-based high-value products

The utilization of biomass, the only carbon-bearing renewable energy source, is critical for environmental and energy sustainability as well as carbon neutrality. Pyrolysis is the efficient conversion of biomass to fuel gas, liquid oil, and solid char. It is necessary to understand the mechanism of biomass pyrolysis for valuable and efficient utilization. In this review, recent progress with respect to biomass pyrolysis properties, the pyrolysis process, and product upgrading strategies focusing on carbon-based high-value liquid fuels and carbon-bearing materials are summarized. First, the correlations between the pyrolysis behavior and biomass structure and process conditions are considered. The mechanisms of the biomass pyrolysis of hemicellulose, cellulose, and lignin as well as the potential effect of inorganic matter on biomass pyrolysis are discussed. Furthermore, the regulation and controlling strategies for the biomass pyrolysis of high-value products are outlined. Finally, the challenges and prospects are discussed in order to provide a comprehensive picture of biomass pyrolysis development, which is significant for the understanding of biomass pyrolysis and the development of biomass utilization technology.