Nickel molybdenum carbides: Synthesis, characterization, and catalytic activity in hydrodeoxygenation of anisole and ethyl caprate

Mo- and Ni-containing carbide catalysts were prepared by a Pechini-based method using citric acid as a complexing agent. All the catalysts were characterized by temperature-programmed reduction, X-ray diffraction (XRD), X-ray photoelectron spectroscopy, and N-2 and CO sorption. The XRD experiments showed that the bimetallic systems contain phases: beta-Mo2C and Mo3Ni2C and an alloy Ni chi Mo1-chi with a high nickel content. The catalysts were tested in the hydrogenation of ethyl caprate and anisole. For the process with ethyl caprate, it was shown that the catalytic activity rises with an increase of the carbide phase content in the bimetallic catalysts. Further addition of nickel increases the amount of the Ni-Mo alloy, which leads to a drop in the catalytic activity and to an increase in the contribution of the decarboxylation pathway. The study of the carbide catalysts in anisole hydrogenation showed that a rise in the Ni/Mo ratio leads to an increase in activity. (C) 2017 Elsevier Inc. All rights reserved.