Preparation of Fe promoted MoS2 catalysts for the hydrodeoxygenation of p-cresol as a model compound of lignin-derived bio-oil

Abstract

Fe promoted MoS2 catalysts were prepared by one-step hydrothermal method and then applied into the hydrodeoxygenation (HDO) of p-cresol as a model compound of lignin-derived bio-oil. The as-prepared samples had FeS2 and MoS2 phases with low crystallinity. After further hydrogen-treatment at 250 °C in dodecane, some peaks to FeS phase were observed. The surface area of Fe promoted MoS2 catalyst decreased firstly and then increased with Fe content in the catalysts increasing. In the HDO of p-cresol, the addition of Fe sulfides into MoS2 enhanced conversion and toluene selectivity. When the Fe/Mo molar ratio is 0.7:1, the conversion and deoxygenation degree reached up to 96.3% and 95.7% after reaction at 250 °C for 3 h, respectively. The high HDO activity was attributed to the synergistic effect and contact surface area between Fe sulfides and MoS2. During the HDO recycling reaction, the deactivation was observed, which resulted from the sulfur loss and the formation of Fe oxides, but its activity could be regenerated after a simple sulfuration procedure.