Deep Desulfurization of Light Oil (Part 1) Hydrodesulfurization of Methyl-substituted Benzothiophenes and Dibenzothiophenes in Light Gas Oil.

Abstract

In deep hydrodesulfurization (HDS) of polyaromatic sulfur-containing compounds in light gas oil catalyzed by Co-Mo/Al2O3, the behavior of methyl-substituted benzothiophenes, monomethyldibenzothiophenes (C1-DBTs) and dimethyldibenzothiophenes (C2-DBTs) was traced under the following could be 2,3,7-trimethylbenzothiophene. The conversions of C1-DBTs other than 4-methyldibenzothiophene (4-MDBT) were very close to the conversion of nonsubstituted DBT.The behavior of three kinds of C2-DBTs other than 4,6-dimethyldibenzothiophene (4,6-DMDBT) was very similar to that of 4-MDBT.These C2-DBTs were deduced to be DBT substituted with a methyl group at 4-position. These results suggest that substitution only at 4-and 6-positions retards the HDS rate of DBT in light gas oil.

Inhibitory Study for Joint Reactions of Hydrodesulfurization and Hydrodenitrogenation during Hydrotreating of Vacuum Gas Oil

“…Thirdly is the type of sulfur compound, activation energy for total sulfur almost higher than individual, Steinner and Blekkan [14] found that the activation energy for total sulfur of light gas oil is (119.966) KJ/mol depending on contains of sulfur compound in oil. For present study these results disagree with Kabe et al [15] who found (100.32) KJ/mol for DBT, this comparison with the same individual sulfur compound.…”

Hydrodesulfurization of Refractory Sulfur Species. 1. Selective Hydrodesulfurization of 4,6-Dimethyldibenzothiophene in the Major Presence of Naphthalene over CoMo/Al2O3 and Ru/Al2O3 Blend Catalysts

“…4,6-DMDBT must compete for the hydrogenation active site with aromatic partners of dominant presence in the gas oil as observed in previous , and the present studies. Hence, the selective hydrogenation of 4,6-DMDBT is very essential to accelerate its desulfurization.…”

Deep Hydrodesulfurization of Light Gas Oil. 1. Kinetics and Mechanisms of Dibenzothiophene Hydrodesulfurization

“…To elucidate the HDS mechanisms of such dibenzothiophenes as 4-MDBT and 4,6-DMDBT, we previously examined the reaction kinetics of these compounds in detail (Kabe et al, 1993a;Zhang et al, 1996). Some groups have also reported the retention of 4-MDBT and 4,6-DMDBT even under deep desulfurization conditions and have demonstrated that the HDS rates were remarkably retarded only by substitution at the 4-and 6-positions of DBT (Kabe et al, 1992(Kabe et al, , 1993bAmorelli et al, 1992;Ma et al, 1994). However, the kinetics of DBTs in HDS of light gas oil, and especially of 4-MDBT and 4,6-DMDBT, have largely been ignored.…”