Effect of supercritical deposition synthesis on dibenzothiophene hydrodesulfurization over NiMo/Al₂O₃ nanocatalyst

Abstract

in Wiley InterScience (www.interscience.wiley.com).The synthesis of two NiMo/Al 2 O 3 catalysts by the supercritical carbon dioxide/methanol deposition (NiMo-SCF) and the conventional method of wet coimpregnation (NiMo-IMP) were conducted. The results of the physical and chemical characterization techniques (adsorption-desorption of nitrogen, oxygen chemisorption, XRD, TPR, TEM, and EDAX) for the NiMo-SCF and NiMo-IMP demonstrated high and uniform dispersed deposition of Ni and Mo on the Al 2 O 3 support for the newly developed catalyst. The hydrodesulfurization (HDS) of fuel model compound, dibenzothiophene, was used in the evaluation of the NiMo-SCF catalyst vs. the commercial catalyst (NiMo-COM). Higher conversion for the NiMo-SCF catalyst was obtained. The kinetic analysis of the reaction data was carried out to calculate the reaction rate constant of the synthesized and commercial catalysts in the temperature rang of 543-603 K. Analysis of the experimental data using Arrhenius' law resulted in the calculation of frequency factor and activation energy of the HDS for the two catalysts. V

Preparation and Characterization of Mesoporous MoO3/TiO2 Composite with High Surface Area by Self-Supporting and Ammonia Method

“…In contrast, control sample relatively favors the HYD route (53.5%) with CHB and THDBT selectivity of 46 and 7.5%, respectively. These differences are in agreement with the results reported in the literature for DBT HDS over highly dispersed catalyst prepared via supercritical deposition or hydrothermal deposition [37,38]. The highly dispersed catalyst has the increased proportion of the edge sites.…”

A process for producing ultraclean gasoline by coupling efficient hydrodesulfurization and directional olefin conversion

“…Therefore, removal of sulfur‐containing compounds and olefins in gasoline has become a key and common focus both in the petroleum refining industry and environmental catalysis. It has been widely recognized that hydrotreating is the most important technique for producing clean transportation fuels in industrial pratice . Moreover, it is well known that for diesel fuels increasing hydrotreating severity (e.g., by increasing operating pressure or/and temperature) can realize both deep desulfurization and cetane improvement, but for gasoline fuels, especially fluid catalytic cracking (FCC) gasoline, this may cause excessive hydrogenation of olefins in gasoline, giving rise to serious octane loss …”

A novel approach for modulating the morphology of supported metal nanoparticles in hydrodesulfurization catalysts

“…14 Another method for improving HDS performance of alumina-supported catalysts is to introduce chelating agents such as ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and 1,2-cyclohexanediamine-N,N,N,N-tetraacetic acid (CyNTA), [15][16][17][18][19] or modification elements such as phosphorus and fluorine, [20][21][22] which can weaken the metal-alumina interaction and thus increase the stacking of metal sulfides, but lead to the formation of large active metal particles with a lower dispersion and thereby decrease the number of active sites. 23 To achieve higher dispersion of active metals on supports, several methods including the equilibrium deposition filtration (EDF), 24,25 the sonochemical and chemical vapor deposition, 26 and the supercritical carbon dioxide/methanol deposition were proposed, 27 but the enhanced dispersion resulting from the strengthened metal-support interaction was outweighed by the accompanied formation of excessive type I active metals that are disadvantageous for the adsorption and HDS of sterically hindered alkyl-substituted DBTs.…”