Affiliation: | aInstituto Tecnológico de Ciudad Madero, División de Estudios de Posgrado e Investigación, Depto. de Ing. Química, J. Rosas y J. Urueta, C.P. 89440, Cd. Madero, Tamps., México, Mexico bInstituto Mexicano del Petróleo, Programa de Ingeniería Molecular, Eje Central L. Cárdenas 152, 07730 México D.F., Mexico cUniversidad Autónoma Metropolitana-Iztapalapa, Departamento de Ingeniería de Procesos e Hidráulica, Av. Rafael Atlixco 186, Col Vicentina, Iztapalapa, 09340 México D.F., Mexico |
Abstract: | A study on the catalytic properties of the transition metals (Ni,Co,Mo)-carbides, -nitrides for thiophene and dibenzothiophene hydrotreating was conducted. The (Ni,Co)-Mo carbides and the corresponding (Ni,Co)-Mo nitride phases showed a catalytic activity higher than conventional bimetallic (Ni,Co)-Mo sulfides. In addition, a study was done on the effect of the atomic ratios, i.e., 0.1 ≤ M+/(M+ + Mo) ≤ 0.9 where M+ stands for Ni or Co, and the concentration of promoters such as phosphorous, which was a structural stabilizing agent. The catalytic performance of the bimetallic NiMo and CoMo carbides and nitrides was studied using thiophene and dibenzothiophene hydrodesulfurization (HDS) as model reactions at 623 K and P = 1 atm. The catalytic activity of the dispersed carbide and nitride phases on the alumina carrier was more significant than that of the reference catalysts, alumina supported NiMo-S and CoMo-S. The metallic character of the NiMo and CoMo carbides was evidenced by their higher hydrogenation activity in thiophene HDS, while the nitrides favored both hydrogenation and hydrogenolysis type reactions. |