NiMo and NiW Nanostructured Catalysts of Thiophene Oxidation, Obtained via Laser Electrodispersion

New bimetallic catalysts based on Ni and Mo or W oxide nanoparticles deposited on alumina are obtained via the laser electrodispersion of tightly compacted binary mixtures of NiMo and NiW powders. SEM, TEM, and XPS show that both components of each pair are uniformly distributed over a carrier’s surface in the form of nanoparticles of 4–7 nm in size. Metals on the catalyst’s surface are predominantly in an oxidized state. The catalytic activity of NiMo/Al2O3 and NiW/Al2O3 pairs is compared using examples of the oxidation of thiophene and dibenzothiophene with hydrogen peroxide. High reagent conversion on such catalysts with ultra-low metal contents (<0.01 wt %) is maintained by continually repeating the process. Introducing a zwitterionic liquid with sulfo group into the reaction mixture results in additional improvement of catalyst efficiency.