Synergetic regulation mechanism of K-assisted bamboo gasification for porous char and H2-rich syngas poly-generation

Poly-generation of porous char and H₂-rich syngas is a key technology for the full and high-value use of carbon and hydrogen elements in biomass. In this study, the synergistic evolution and regulation mechanisms of H₂ and porous carbon during K-assisted bamboo gasification were investigated using fixed-bed pyrolysis-gasification system. The results show that, due to steam activation, both the H₂ production rate and the physicochemical properties of char initially increase and then decline with prolonged gasification time, reaching their peak in the middle stage of the process. The hydrogen conversion rate further indicates that partial gasification achieves higher production efficiency, which is favorable for the poly-generation. K accelerates the evolution of both char and H₂, enhancing their quality and ultimately enabling the poly-generation of 31.5 mmol/g H₂ and porous carbon with a S_BET of 1917 m²/g. Moreover, K promotes oxygen enrichment in char, particularly the incorporation of O=C-OR and C=O groups on the char surface, thereby improving the functional applicability of the carbon.