Biocrude production by catalytic hydrothermal liquefaction of wood chips using NiMo series catalysts

Abstract

In this work, hydrothermal liquefaction of wood chips was studied for biocrude production using a mix of Ni–Mo nitrides and carbides. The catalytic materials were synthesized by a temperature-programmed reaction method at 800 °C under a hydrogen atmosphere with nickel loads from 0 to 20 wt%. Lignin contained in the lignocellulosic biomass was successfully release via Kraft process. Hydrothermal liquefaction was carried out in a batch reactor at 320 °C with an initial pressure of 1000 psi of H2. According to characterization results, nanostructured catalysts with a mix of Ni2Mo3N/Mo2C compo4unds were obtained. NiMo series catalysts composition varies with nickel loads. The catalytic activity shows a reduction in the amount of solid products and an increase in the production of gaseous products as a function of the increase Ni loadings on the catalyst. The most optimal production of biocrude was obtained with the NiMo-10 catalyst, since 81.43% of the total product corresponded to water soluble products (WPS) fraction and the oil fraction, while the solids fraction represented the 6.43% of the total product. Hydrothermal liquefaction catalytic processes were selective towards WSP fraction, improving biocrude quality and favoring biocrude conversion into advanced biofuels.