Experimental proof of thiophene hydrodesulfurization reaction steps by isotope (14C) labeled thiophene

Hydrodesulfurization of thiophene has been studied over alumina supported sulfided molybdena, nickel-promoted molybdena and over nickel (Mo, NiMo and Ni) catalysts. The experiments were carried out with a mixture of thiophene, labeled with radioactive carbon (thiophene-[G-]-14C) and of non-radioactive tetrahydrothiophene (1:1 mol ratio) in a micro catalytic system. It was established, that the main products were tetrahydrothiophene-14C, 1-butene-14C, 2-butene-14C, butane-14C. Tetrahydrothiophene-14C was a major intermediate in the conversion of thiophene—14C in the experimental condition applied. The amounts of converted tetrahydrothiophene on the catalysts were substantially higher than those of thiophene under the same conditions. Hydrothiophene and dihydrothiophene—14C were intermediate products in the hydrodesulfurization of thiophene and tetrahydrothiophene. The hydrodesulphurization of tetrahydrothiophene was paired with dehydrogenation, producing small amounts of thiophene. The experimental results have been considered in the discussion of the mechanism of thiophene and tetrahydrothiophene desulfurization reaction pathway.

Molecular simulation on mechanism of thiophene hydrodesulfurization on surface of Ni2P

Hydrodesulfurization reaction, as the last step of hydrothermal cracking reaction, is of great significance for the reduction of viscosity and desulfurization of heavy oil. Based on Density Functional Theory and using Dmol3 module of Materials Studio, this research simulated the adsorption and hydrodesulfurization of thiophene on Ni2P (001) surface, and discussed the hydrodesulfurization reaction mechanism of thiophene on Ni2P (001) surface. It was found that the direct hydrodesulfurization of thiophene had more advantages than the indirect hydrodesulfurization of thiophene. Finally, the optimal reaction path was determined: C4H4S+H2→C4H6.

Fabrication of Nimo Nanostructured Catalyst via Ultrasonic-Assisted Combustion Method Used in High Efficiency Thiophene Hydrodesulfurization: Influence of Organic Compound Type

The authors have requested that this preprint be withdrawn due to erroneous posting.

Comparative Study Between two Reaction Kinetic Mechanisms of Thiophene Hydrodesulphurization over CoMo /gama - Al2O3 Supported Catalyst

The kinetic study of the thiophene hydrodesulphurisation process was carried out for CoMo/gama-Al2O3 catalyst, at temperatures between 175 and 275 �C, pressure ranged from 30bar to 60 bar and the liquid hourly space velocity from 1h-1 to 4 h-1. For the reaction mechanism, the Langmuir-Hinshelwood-Hougen-Watson model (LHHW) was used and two kinetic models were proposed: the first model, that considered that H2 is adsorbed on a different type of active center than thiophene and the second model, that considered that the two reactants are adsorbed on the same type of active sites. The values obtained for the average relative error (ARE) and the correlation coefficient between the experimental and the calculated data (R2) indicate that the Langmuir-Hinshelwood model, describing the adsorption on two active sites, best describes the kinetics of the thiophene hydrodesulfurization reaction over CoMo/gama-Al2O3 tested catalyst.