Surface engineering of carbon supported CoMoS– an effective nanocatalyst for selective deoxygenation of lignin derived phenolics to arenes

Abstract

We report a viable synthesis route to prepare Co promoted MoS2 nanocatalyst supported on an activated carbon for the selective hydrodeoxygenation of lignin derived phenolics in a liquid phase. The key aspect of this strategy is to use activated carbon as support with weak metal-support interaction that promotes the formation of Co-Mo-S phase, which is inhibited in alumina supported CoMoS2 due to the strong metal-support interaction. The as-synthesized catalyst contained Co9S8 and MoS2 phases dispersed on the support, which during reduction at 450 °C formed Co-Mo-S phase that is active for deoxygenation. To validate the claim, the activity of the reduced catalyst was compared with the unreduced catalyst for guaiacol conversion. As such 92 % softwood lignin was converted after 5 h reaction time, producing 76 % liquids with 75 % deoxygenation. The loss of catalytic activity after five catalytic cycles was attributed to the reduction in catalyst surface area, sulphur leaching and metal sintering.