Hydrogenation destructive

The reaction takes place above 20 atms press and above 482°, with suitable H2 partial press and contact time necessary to obtain destructive hydrogenation without the formation of poly merized material. The resulting hydroformed naphthas may be halogenated, sulfonated or nitrated... 

Katsobashvili A low-pressure, catalytic process for the destructive hydrogenation of petroleum residues. Piloted in the USSR in the 1950s. 

Hydrogenation of bituminous coal was found more difficult than that of brown coal, chiefly because the primary products of hydrogenation of bituminous coal have a higher percentage of asphaltenes (material soluble in benzene but insoluble in w-hexane). The slower rate of destructive hydrogenation of asphaltenes is reflected in the much lower throughput of bituminous coal per unit volume of reactor. 

Mtolera MSP, Collen J, Pedersen M, Semesi AK (1995) Destructive Hydrogen Peroxide Production in Eucheuma denticulatum (Rhodophyta) During Stress Caused by Elevated pH, High Fight Intensities and Competition with Other Species. Eur J Phycol 30 289... 

The hydrodesulfurization process can fall into either the destructive or nondestructive category. However for heavy feedstocks some hydrocracking is preferred, if not necessary, to remove the sulfur. Thus, hydrodesulfurization in this context falls into the hydrocracking or destructive hydrogenation category. The basic chemical concept of the process remains the same, that is, to convert the organic sulfur in the feedstock to hydrogen sulfide. 

Although the definition of the two processes is purely arbitrary it is generally assumed that destructive hydrogenation (which is characterized by the cleavage of carbon-to-carbon linkage and is accompanied by hydrogen saturation of... 

On the other hand, destructive hydrogenation (hydrocracking) is character-... 

Several methods, involving solvent extraction or destructive hydrogenation, can accomplish the removal of aromatic hydrocarbons from naphtha. By destructive hydrodegation methods, aromatic hydrocarbon rings are first ruptured and then saturated with hydrogen, which converts aromatic hydrocarbons into the odorless, straight-chain paraffinic hydrocarbons required in aliphatic solvents. 

Studies of hydrogenation, including destructive hydrogenation (Nemtsov, Prokopets, Dyakova), reported in the 1930 s, may have been utilized by now for industrial processes. A. V. Frost has been conducting research on the kinetics of catalytic reactions and on catalytic cracking. Frost and M. D. Tilicheev are co-editors of a series of publications on physical constants of hydrocarbons which may be used as a source of information on the synthesis of individual hydrocarbons. Other Russian groups have contributed (N. D. Zelinskii, A. D. Petrov) to this field. Some of this work involves catalytic reactions however, in this review mere mention of it may suffice. 

In connection with the research on destructive hydrogenation at the Institute of High Pressures, Maslyanskii (224) passed benzene at 475° under 200 atm. hydrogen over molybdenum oxide (1 mole CeH6 16 moles Ha) to produce 58% methylcyclopentane, 14% cyclohexane, 8% 2-methyl-pentane, 5% n-hexane, and 8% unreacted. Over molybdenum sulfide the product distribution was similar. The preparation of these catalysts was described by him in 1940 (223). Isomerization and other conversions accompanying destructive hydrogenation were also pointed out by Prokopets and by others (257,311,314). 

For industrial hydrogenation of vegetable and animal oils in Russia a Raney type nickel was prepared by Bag and co-workers (64). Preparation of detergents from hydrogenated fats has been reported (11). Reviews of these so-called skeleton catalysts were published by Russian investigators, for instance, by Lel chuk and co-workers (197). These catalysts have also been discussed with reference to hydrocarbon synthesis from water gas (148). Lel chuk (197) states that Raney nickel is more drastic for water gas synthesis than are the skeleton nickel catalysts prepared by Bag, and that Bag s copper-nickel skeleton catalysts approach nickel in their activity. Destructive hydrogenation under mild conditions was said to be possible with Bag s skeleton catalyst as described by Lel chuk. 

Pure sulfur compounds containing 9 or 10 carbon atoms were examined in the presence of silica-alumina at 250-300° (391). Liberation of hydrogen sulfide, destructive hydrogenation and hydrogen disproportionation took place forming disulfides, mercaptans, and olefins. 

Ipatieff was, first of all, a brilliant and able teacher who preferred the title of Professor to any other. His research activity of a purely scientific nature brought with it unusual industrial success, and many plants, operating all over the world, are based on catalytic reactions discovered by him. Among the most important of his contributions are the introduction of high-pressure techniques in chemistry and chemical industry, destructive hydrogenation, the production of acetone from propyl alcohol, and the production of high-octane aviation fuel by the reactions of polymerization, alkylation, and isomerization. He was the first to demonstrate the specificity of catalysts and the use of mixed catalysts and promotors. 

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