Reaction network of pyridine hydrodenitrogenation over carbide and sulfide catalysts

On Catalytic Behavior of Bulk Mo2C in the Hydrodenitrogenation of Indole over a Wide Range of Conversion Thereof

The catalytic activity of bulk molybdenum carbide (Mo2C) in the hydrodenitrogenation (HDN) of indole was studied. The catalyst was synthesized using a temperature-programmed reaction of the respective oxide precursor (MoO3) with the carburizing gas mixture of 10 vol.\% CH4/H2. The resultant material was characterized using X-ray diffraction, CO chemisorption, and nitrogen adsorption. The catalytic activity was studied in the HDN of indole over a wide range of conversion thereof and in the presence of a low amount of sulfur (50 ppm), which was used to simulate the processing of real petroleum intermediates. The molybdenum carbide has shown high activity under the tested operating conditions. Apparently, the bulk molybdenum carbide turned out to be selective towards the formation of aromatic products such as ethylbenzene, toluene, and benzene. The main products of HDN were ethylbenzene and ethylcyclohexane. After 99% conversion of indole HDN was reached (i.e., lack of N-containing compounds in the products was observed), the hydrogenation of ethylbenzene to ethylcyclohexane took place. Thus, the catalytic behavior of bulk molybdenum carbide for the HDN of indole is completely different compared to previously studied sulfide-based systems.

Metal non-oxide nanostructures developed from organic-inorganic hybrids and their catalytic application

The rational design of metal non-oxides is important for their catalytic application, which is however limited by the fact that the current synthetic strategies are short of effective control over formation reactions. Recently, the hybrids evenly integrating organic with inorganic molecules on a nanoscale significantly provided quasi-homogeneous reactions towards well-defined nanocatalysts of metal non-oxides, in which their structures and properties can be modulated in a wide range. Focusing on the nanostructures and the related catalytic behaviors, this feature article seeks to provide some control on the key structures and properties of metal non-oxides (e.g. carbides, nitrides, sulfides and selenides). It is thus anticipated to shed some light on the development of emerging materials for efficient catalysis, especially those used in energy utilization.