Mexican Institute of Petroleum

About: Mexican Institute of Petroleum is a government organization based out in Mexico City, Mexico. It is known for research contribution in the topics: Catalysis & Asphaltene. The organization has 3273 authors who have published 4170 publications receiving 87269 citations.

Effect of the particle size on the activity of MoOxCy catalysts for the isomerization of heptane

Abstract: Molybdenum trioxide samples having apparent particle sizes (APS) of 5 and 20 μ.m were partially reduced under flow of a mixture of H2/n-heptane during 4 h. X-ray diffraction and Raman spectroscopy showed the typical structural transformation of MoO3 into MoO x C y and MoO2. These structural changes occur preferentially on the {0k0} planes. After the reduction treatment the resulting materials, having surface areas of 23 and 53 m2/g, were evaluated in the isomerization of n-heptane at 643 K and 18.5 bar. The catalyst with an APS of 20 μ.m showed a maximum conversion around 70%, while for the catalyst with an APS of 5 μ.m the maximum conversion was 34%. The lower activity of the 5 μ.m MoO x C y catalyst seems to be related to a faster rate of formation of oxygen vacancies and rearrangement of the lattice into a more stable and less active structure in the case of small-size particles, due to a higher concentration of terminal Mo=O bonds along the a- and b-axes, which facilitate the electrophilic attack by hydrogen on the (010) plane.

Carbon-Modified Alumina and Alumina−Carbon-Supported Hydrotreating Catalysts

Abstract: Two types of supports, carbon-modified alumina and alumina−carbon, were prepared in this investigation. These supports were used to prepare hydrotreating (HDT) catalysts for Maya heavy crude. It was found that, when carbon was added to the alumina matrix and the carbon was then burned, pores having larger diameter were generated. The average pore diameter of the support increased with increasing amount of carbon in the alumina. However, when the carbon was not burned, the pore size decreased with added carbon. The hydrotreating activity results show that, because of the larger pore diameter and higher pore volume, the modified-alumina-supported PCoMo catalysts have slightly higher activities than the alumina−carbon-supported catalysts. The effects of additives, boron and phosphorus, on the hydrotreating of heavy oil were also compared. It was found that P-containing catalysts have higher activities than B-containing catalysts. It was also found that, when boron-containing catalyst were prepared at higher ...