Effect of morphology properties of NiW catalysts on hydrodesulfurization for individual sulfur compounds in fluid catalytic cracking diesel

Gallium Modified HUSY Zeolite as an Effective Co‐support for NiMo Hydrodesulfurization Catalyst and the Catalyst's High Isomerization Selectivity

“…This result demonstrates that Brønsted acidity,e specially medium and strong Brønsted acidity from the acidic co-supports, plays av ery important role in the HDS activity of 4,6-DMDBT,e specially in the selectivity of its HDS pathway.T he main product of 4,6-DMDBT HDS over NiMo/ASA-A was 3,3'-DMCHB, and the HYD pathway selectivity reached as high as 82 %, indicating that 4,6-DMDBT was mainly transformed by the HYD pathway over nonacidic catalysts, which shows good consistency with the results reported elsewhere in the literature. [4,9,11] However,the main products of 4,6-DMDBT HDS over gallium-modified HUSY zeolite-containing catalysts were 3,4'-DMBP and 4,4'-DMBP and ISO-MIPT,i ndicating that 4,6-DMDBT was mainly trans- Table 5.…”

“…[2][3][4][5] The catalysts commonly employedi nt he petrochemicali ndustryt or emove sulfur atoms from transportation fuels are cobalt-or nickel-promoted MoS 2 or WS 2 supported on g-alumina. [3][4][5][6] Highly refractory sulfur-containingc ompounds such as 4,6-DMDBT undergo HDS by direct desulfuriza-tion (DDS) and hydrogenation desulfurization (HYD)o verc onventional catalysts: [2,4,[7][8][9][10] DDS produces 3,3'-dimethylbiphenyl (3,3'-DMBP) as the desulfurized product, andH YD produces tetrahydro-and hexahydro-4,6-DMDBT as intermediates, which can be further desulfurized to yield 3,3'-dimethylcyclohexylbenzenes (3,3'-DMCHB) and 3,3'-dimethylbicyclohexyls (3,. Due to the hindrance caused by the two methyl groups at the 4a nd 6p ositions, whichs trongly prevent the adsorption of the sulfur atom at the active sites of the catalysts through sigma-adsorption, sulfur removal from 4,6-DMDBT mainly proceeds through the HYD pathway.…”

Effect of pore size distribution (PSD) of Ni-Mo/Al2O3 catalysts on the Saudi Arabia vacuum residuum hydrodemetallization (HDM)

“…10 ml oxidic catalyst (20-40 mesh) was loaded in the reactor. The catalyst was presulfided [27] with a solution of 2 wt.% CS 2 /cyclohexane at 593 K, total pressure of 4 MPa for 6 h, and liquid hourly space velocity (LHSV) of 6.0 h −1 . After the sulfidation, the flow was switched to VR and the following operating conditions were adjusted: temperature of catalyst bed 663 K, LHSV of 0.5 h −1 , H 2 /oil = 1000 m 3 /m 3 and total pressure of 10 MPa.…”

Fe/C and FeMo/C hybrid materials for the biphasic oxidation of fuel contaminants

“…Organic sulfur molecules present in petroleum are mercaptans, represented by the general formula S-H, and heterocyclic compounds, such as sulfides, polysulfides, benzothiophenes and their derivatives. 6,7 Hence, in recent decades, research into clean fuels, including desulfurization and denitrogenation, has become an important subject for environmental catalysis studies worldwide. 4,5 The combustion of these compounds leads to the emission of SO x and NO x , which can cause critical health problems and are precursors of acid rain.…”