Nickel, hydrocracking

Toluene is dealkylated to benzene over a hydrogenation-dehydrogenation catalyst such as nickel. The hydrodealkylation is essentially a hydrocracking reaction favored at higher temperatures and pressures. The reaction occurs at approximately 700°C and 40 atmospheres. A high benzene yield of about 96% or more can be achieved ... 

Kinetics studies of the hydrotreatment (and hydrocracking) of VR has led to the conclusion that most of the metals, sulfur and nitrogen removal takes place during the first 50% of the whole VR conversion [119-123], More than one reactor was needed for HDM and HDS of a Maya VR, when HDT is used as feed pretreatment [119,120], Although vanadium removal appears easier and faster than nickel removal, their kinetics results showed very similar values of the activation energy for the demetallization reactions [122],... 

Other catalytic hydrocarbon reactions indude decomposition of olefins over a powdered nickel catalyst [84], hydrogenation of alkenes, hydrocracking of cycloalk-enes, and water-gas shift reactions [64]. 

Hy-C Cracking A hydrocracking process. The catalyst is nickel/tungsten on alumina. Developed by Cities Service Research and Development Company and Hydrocarbon Research. 

Isocracking A hydrocracking process developed and licensed by Chevron Research Company. The catalyst is nickel or cobalt sulfide on an aluminosilicate. First commercialized in 1962 more than 45 units had been built by 1994. See also Isomax. 

Like catalytic cracking, hydrocracking processes generate toxic metal compounds, many of which are present in spent catalyst sludge and catalyst fines generated from catalytic cracking and hydrocracking. These include metals such as nickel, cobalt, and molybdenum. 

Table II. Hydrocracking of Pure Hydrocarbons in the Presence df Nickel-Silica-...

Throughout these studies, no product other than propane was observed. However, subsequent studies by Sinfelt et al. [249—251] using silica-supported Group VIII metals (Co, Ni, Cu, Ru, Os, Rh, Ir, Pd and Pt) have shown that, in addition to hydrogenation, hydrocracking to ethane and methane occurs with cobalt, nickel, ruthenium and osmium, but not with the other metals studied. From the metal surface areas determined by hydrogen and carbon monoxide chemisorption, the specific activities of... 

In a detailed kinetic study, Sridhar and Ruthven [256], using nickel supported on Kieselghur (58% Ni), alumina (14% and 40% Ni) and silica-alumina (5% Ni), showed that over all four catalysts the rates of both hydrogenation and hydrocracking could be correlated according to the power rate law equation... 

Robert B. Anderson. Iron catalysts apparently do not isomerize hydrocarbons however, there is little experimental evidence besides the products of the Fischer-Tropsch synthesis. In hydrocracking of paraffins on nickel and cobalt catalysts the isomerization does not occur. 

The paper deals with some new data concerning the state of the metal after reduction and the catalytic functions of zeolite catalysts containing nickel and platinum. By using the molecular sieve selectivity in the hydrogenation of mesitylene it has been proved that metal (platinum) is contained in the volume of the zeolite crystal. The temperature dependence of the formation of nickel crystals was investigated. The aluminosilicate structure and the zeolite composition influence mainly the formation of the metal surface which determines the catalytic activity. In the hydrocracking of cumene and disproportionation of toluene a bifunctional action of catalysts has been established. Hydrogen retarded the reaction. 

Hydrocracking is catalyzed by substances that promote cracking and hydrogenation together. Nickel and tungsten sulfides on acid supports and zeolites loaded with palladium are used commercially. 

Raffinate Hydrocracking with Palladium-Nickel— Containing Synthetic Mica-Montmorillonite Catalysts... 

Previous results(2) had shown that a Pd-Ni-SMM catalyst was effective for hydrocracking hexane as well as a raffinate feed. Conclusions showed that this catalyst system when containing two nickel atoms per unit cell (15 wt % nickel) was approximately 15 times more active than a Pd-rare earth-Y zeolite catalyst and 1.2 times more active than Pd-H-mordenite. This same catalyst system (0.7 wt % Pd-15 wt % Ni-SMM) was chosen for our raffinate processing studies. 

A bituminous coal from Utah (Table I) was used in this work. The coal oil (Table II) used was obtained from a bituminous coal by hydrogenation using zinc chloride as the catalyst in a semi-continuous reactor system. Anthracene, phenanthrene, WS9 and NIS used were pure grade chemicals of over 99% purity. H-zeolon was a synthetic mordenite cracking catalyst and was supplied by Norton Chemical Company. NIS-H-zeolon was prepared by spraying nickel on H-zeolon with a subsequent sulfiding operation. NIS-WS -SiO -A1 O. catalyst used was a commercial hydrocracking catalyst. Analyses of reactants and products were done by standard methods. 

TABLE I. - Hydrocracking of in situ crude shale oil over nickel-molybdena catalyst... 

The IFP hydrocracking process features a dual catalyst system the first catalyst is a promoted nickel-molybdenum amorphous catalyst. It acts to remove sulfur and nitrogen and hydrogenate aromatic rings. The second catalyst is a zeolite that finishes the hydrogenation and promotes the hydrocracking reaction. 

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