New method for producing catalyst materials to reduce sulfur content in petroleum fuels

Increasingly strict environmental legislation is being applied to motor vehicle emissions. An important aspect of these regulations is the restriction of the amount of sulfur in vehicle transportation fuels. The process used to modify fuels and remove the sulfur is known as hydrodesulphurization (HDS). The HDS process requires novel catalyst materials that are often difficult to synthesize using traditional methods. Another synthesis method, mechanical alloying (MA), shows potential for producing catalysts but to date is not well documented for this application.

It is known that NEBULA (New Bulk Activity) catalysts based on Ni-Mo-W, are four times more active than typical catalysts and two times more than other advanced formulations. These types of catalysts opened the way to new bulk catalysts with improved catalytic activity in HDS.

In this work, researchers R. Huirache-Acuna, M. I. Flores Z., M. A. Albiter, I. Estrada-Guel, C. Ornelas, F. Paraguay-Delgado, J.L. Rico, L. Bejar-Gomez, G. Alonso-Nunez and R. Martinez-Sanchez, from Centro de Investigación en Materiales Avanzados (CIMAV) and Universidad Michoacana de San Nicolás de Hidalgo in Mexico prepared quaternary alloys of Ni-Mo-W-Al by mechanical alloying. In addition, a process of chemical extraction by alkaline leaching was applied to remove aluminum in order to increase the specific surface area (SSA) and to generate porous materials which were tested in the HDS of dibenzothiophene (DBT) to determine their catalytic activity and selectivity.

The catalyst materials produced were found to have a moderate catalytic activity, due to the synergized effect of small particle and crystal size, and presence of porosity.