Synthesis, Characterization and Catalytic Activity of Supported NiMo Catalysts

Abstract

A study of NiMo catalysts supported on MCM41 modified with alumina prepared by the sol-gel method is presented. Ni-Mo phases were impregnated on the supports using the solution method with the purpose to obtain a material whose hexagonal structure of the MCM41 would not be affected with the addition of these active phases. The impregnation of the metals method used in the present work was outstanding, the textural properties of the catalysts decreased from 42 to 67%. There was a diminution in the textural properties of the catalysts with respect to the supports, nevertheless the prepared materials had more significant textural properties that the conventional catalysts of HDS. The adsorption-desorption isotherms of the catalysts did not change considerably with the support source. By DRX was determined the structural properties of the metallic phases present in the material where phases such as NiMoO 4 , MoO 3 and NiO were observed. Support wall thickness was increased with the incorporation of Ni and Mo metals into the materials. By means of Raman spectroscopy, the presence of MoO 3 and Mo 8 O 26 4-species was corroborated. Through UV-vis where determined NiO of octahedral symmetry as well as Mo of tetrahedral and octahedral symmetry. The main reaction products were biphenyl (BP), cyclohexylbenzene (CHB) and bicyclohexyl (BCH) when the materials were tested in the HDS of DBT.

Hydrotreating Activity of Co-Mo/Al2O3 Promoted with Boron and Phosphorous

“…According to the literature, it was detected that the high HDS and HAD activities were relevant to a reduction in surface area. Martínez-Juárez et al [23] described a decrease in the surface area and increase in the activities of HDS and HAD with the addition of B (1.7 wt. %).…”

Synthesis, characterization and catalytic properties of NiMoP/MCM41-γAl2O3 catalysts for DBT hydrodesulfurization

“…In the spectra of the catalysts a strong band at 390 nm and a broad band between 600 nm and 1000 nm are assigned to the species [Ni 2+ 6O 2− ] [Oh] of octahedral coordination, Ni (Oh). It does not exist an evidence of a doublet at 600-640 nm approximately, characteristic to nickel species of tetrahedral symmetry (Th) [46][47][48].…”

“…In literature [46][47][48] it is mentioned that the Mo O bond referring to tetrahedral molybdenum and Mo O Mo bond of octahedral species exhibit an electronic adsorption at 220-250 nm and 320 nm, respectively [50,51]. At 390 nm there is a band corresponding to Ni (Oh) of octahedral symmetry.…”

Analysis by Temperature-Programmed Reduction of the Catalytic System Ni-Mo-Pd/Al2o3

“…Many studies have focused on the nature and structure of Mo species, and the results of studies employing various characterization techniques indicate that the presence of promoters does not greatly affect the state of Mo species on the Al 2 O 3 surface [20,27]. According to the literature, these bimetallic catalysts are active, both reduced and sulfided [25,30,31], with nickel-molybdenum contents generally of 3-12 wt% Ni and 5-20 wt% Mo [20,[28][29][30][32][33][34].…”