Co-Production of Aromatics and Hydrogen from Catalytic Pyrolysis of Biomass Using Fe-Mg-Co Bifunctional Catalysts

Abstract

biomass pyrolysis was investigated with the Fe-Mg-Co catalysts in a fixed bed reactor, with focus on the change of the yields of char, tar and gaseous products. The catalysts were prepared by impregnation method with different Fe, Mg, Co mass ratios. Among the catalysts, the 15 Fe 0.8 Mg 0.7 Co catalyst is the most efficient in upgrading the pyrolysis of biomass，and the syngas yield is 47.85 %.  Experimental results showed that the yields of hydrogen and light aromatics could be greatly improved with Fe-Mg-Co catalysts. The maximum hydrogen yield of 113.48 ml/g is obtained with the 15 Fe 0.8 Mg catalyst at 700 ℃. Comparable trends were observed with increasing temperature, which had a positive effect on cracking reactions of tar. Additionally, Fe-Mg-Co not only promoted cracking and restructuring of tar but also enhanced the thermal decomposition of heavier tar at the higher temperature, which resulted in the improve of BTX (benzene, toluene, xylene), PCN ( phenol, cresol, naphthalene) yields. The best conditions for the formation of BTX, PC and naphthalene are 15 Fe 0.8 Mg 0.7 Co at 700 ℃.