Selective ring opening of decalin over bifunctional RuS2/zeolite catalysts

Abstract

The discovery of sulfur-resistant catalysts for selective ring opening (SRO) is an important challenge for refiners, considering the future legislation on cetane index of diesel fuels. In the present work, we studied the properties of RuS 2 supported on several zeolites in gas-phase decalin hydroconversion at high hydrogen pressure (5 MPa) in the presence of 0.8% H 2 S concentration. Catalytic bifunctionality was investigated by changing the Ru loading or support acidity. The addition of RuS 2 strongly improved catalytic activity of an HY zeolite, decreased coke deposition and dehydrogenation and increased selectivity towards RO products. The mechanism mainly proceeds from skeletal isomerization induced by the acidity of the zeolite but the hydrogen activation properties of RuS 2 are beneficial to the activity and stability of the catalyst.

Influence of the Ir content and the support on the thiotolerance of the Ir/SiO2‐Al2O3 catalysts for selective ring opening of decalin

“…Recently, Catherin et al found similar results in SRO of decalin; the addition of S to Ru catalysts supported on zeolite HY decreased coke formation and dehydrogenated products. [ 50 ] Therefore, some increase of the cracking reaction in the presence of sulphur could be due to the lower deposition of coke, as compared with the experiments in the absence of sulphur. Monteiro et al postulated that the main effect of the S is to modify the balance between the acid and metal activity, which alters the reactivity of the intermediate products and favours the cracking reactions.…”

“…Consequently, it could be concluded that the increase of metal content from 1 wt% to 2 wt% has little influence on decalin conversion as it was previously reported for RuS 2 /HY zeolite and Pt/Beta zeolite. [ 50,51 ]…”

“…Monteiro et al postulated that the main effect of the S is to modify the balance between the acid and metal activity, which alters the reactivity of the intermediate products and favours the cracking reactions. [ 50 ] However, the strong decrease of metal function at the highest S concentration (20 ppm) leads to a lower yield to dehydrogenated products and consequently less cracking products since dehydrogenated products are more easily cracked than saturated compounds. [ 68 ]…”

Effect of Pd Precursor Salts on the Chemical State, Particle Size, and Performance of Activated Carbon-Supported Pd Catalysts for the Selective Hydrogenation of Palm Biodiesel

“…Supported Pd catalysts are commonly used for selective hydrogenation in the refining and petrochemical industry [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ]. When Pd catalysts are prepared via aqueous impregnation, the Pd precursor salts and corresponding precursor solutions with different pH values are important factors that could be used to control the interactions (e.g., electrostatic or ion-exchange interactions) between the Pd precursors and supporting materials such as alumina [ 12 , 13 , 14 ], silica [ 15 , 16 , 17 , 18 , 19 ], and activated carbon (AC) [ 20 , 21 ].…”

“…Supported Pd catalysts are commonly used for selective hydrogenation in the refining and petrochemical industry [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ]. When Pd catalysts are prepared via aqueous impregnation, the Pd precursor salts and corresponding precursor solutions with different pH values are important factors that could be used to control the interactions (e.g., electrostatic or ion-exchange interactions) between the Pd precursors and supporting materials such as alumina [ 12 , 13 , 14 ], silica [ 15 , 16 , 17 , 18 , 19 ], and activated carbon (AC) [ 20 , 21 ]. The microporous and mesoporous structures, surface properties, and functional groups of supporting materials also play important roles in controlling the dispersion and chemical state of Pd, hence it influences the performance of obtained Pd catalysts [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ].…”