Catalytic conversion of lignocellulosic biomass to liquid fuels by composite metal oxide in supercritical methanol: Effect of reaction temperature

Two kinds of Cu-based composite metal oxide (CMO) catalysts were prepared by using hydrotalcite as precursors. XRD analysis shows that the addition of Ni reduces the crystallinity, which makes the grains smaller and is favorable for the dispersion of various metals. The catalytic performance of the two kinds of catalysts for the liquefaction of lignocellulosic biomass was investigated in supercritical methanol (sc-MeOH). The main liquid products are acids and furan in the absence of catalyst. After adding the catalyst, the products are mainly ketones and alcohols, indicated that CMO effectively promoted the conversion of biomass catalytic liquefaction into liquid fuel. The effects of reaction temperature on the composition and distribution of liquefaction products were discussed. The results showed that the critical temperature of methanol is the key to the hydrogenolysis of lignocellulosic biomass. CMO can effectively catalyze the cracking of methanol and provide hydrogen equivalent for the hydrogenolysis of biomass when the reaction temperature is higher than the critical temperature of methanol (239℃). The higher the temperature, the more the hydrogen equivalent provided by the methanol cleavage, and the components of the biomass liquefied product as liquid fuels increase gradually as the temperature increases. © 2020, Editorial Board of Acta Energiae Solaris Sinica. All right reserved.