1136-85-2Relevant academic research and scientific papers
Gallium Modified HUSY Zeolite as an Effective Co-support for NiMo Hydrodesulfurization Catalyst and the Catalyst's High Isomerization Selectivity
Zhou, Wenwu,Zhou, Yasong,Wei, Qiang,Du, Lin,Ding, Sijia,Jiang, Shujiao,Zhang, Yanan,Zhang, Qing
, p. 9369 - 9382 (2017)
The effects of metal-modified acidic co-supports on the hydrodesulfurization (HDS) activity and isomerization selectivity of highly refractory organosulfur compounds such as 4,6-dimethyldibenzothiophene have been investigated. Y zeolite crystals with high Si/Al ratios and small crystallite sizes were successfully synthesized by a new hydrothermal synthesis approach. The synthesized Y zeolite crystals were ion-exchanged and stabilized. The prepared samples were then modified with different gallium contents using an impregnation method to adjust their acidity properties, and these modified samples were used as co-supports for NiMo sulfide HDS catalysts. The catalyst containing 10 wt.% zeolite Y modified by 2 wt.% gallium (NiMo/2GaY-ASA-A) exhibited the highest HDS activity, with 4,6-dimethyldibenzothiophene (4,6-DMDBT) conversion nearly double the rate of the catalyst without zeolite at 563 K, 4.0 MPa and liquid hourly space velocity (LHSV) of 40 h?1. NiMo/2GaY-ASA-A also exhibited superior isomerization ability, with 3,4′-DMBP, 4,4′DMBP, and 3,6-DMDBT as the main products, indicating that the isomerization pathway was the main reaction route over NiMo/2GaY-ASA-A. The superior catalytic performance is related to the synergistic effect of the proper amount of medium and strong Br?nsted acid sites. The compounds 3,6-DMDBT and 3,7-DMDBT (isomers of 4,6-DMDBT) and 3,4,6-TMDBT and tetra-methyl-DBT (transmethyl products) were detected simultaneously in the HDS product of 4,6-DMDBT for the first time over NiMo/GaY-ASA-A catalysts. Finally, a new reaction network over NiMo/2GaY-ASA-A was proposed.
The Synthesis of All of the Dimethyldibenzothiophenes and Monoethyldibenzothiophenes
Tedjamulia, Marvin L.,Tominaga, Yoshinori,Castle, Raymond N.
, p. 1485 - 1495 (2007/10/02)
The synthesis of all four isomers of the monoethyldibenzothiophenes and all of the sixteen isomers of the dimethyldibenzothiophenes has been accomplished.
