Petroleum hydroprocessing

Another example of the effective role of carbon inertness is the use of carbon-supported catalysts for petroleum hydroprocessing, since in comparison to conventional alumina supports, carbon is exceedingly inert. Thus, when the conversion of a catalyst precursor to the catalytically active phase involves reduction or sulfidation, this is easier and more complete when carbon is the support. The very complete study of De Beer et al. (1984), with a long series of important contributions, initiated by Duchet et al. (1983) provides a clear example of this advantage of a carbon black support, which can be considered as... 

Catalytic Hydroprocessing of Petroleum and Distillates, edited by Michael C. Oballah and Stuart S. Shih... 

Cooper, B. H. Sogaard-Anderson, P., and Nielsen-Hannerup, P., Production of Swedish class I diesel using dual-stage process,in Catalytic Hydroprocessing of Petroleum and Distillates, M.C. oballa, S.S.S. editor. 1994, Marcel Dekker New York. pp. 279-290. 

Hydrorefining A general name for petroleum refining processes using hydrogen gas. See also Hydroprocessing. 

Hydroprocessing, in petroleum refining, 18 654-657 Hydropulping, 10 535 Hydropyrolysis, coal liquefaction, 6 854 Hydroquinolines, 21 198-199 Hydroquinone (HQ) from benzene, 3 620 as a black-and-white chemical reducing agent, 19 205-206 in bleaching preparations, 7 847 clathrates, 14 160 dye releaser, 19 291-292 inclusion compounds in, 14 172, 174 intermediate used in oxidation hair dyes, 7 858t... 

Tops0e, H. Bartholdy, J. Clausen, B.S., Candia, R. results presented at the ACS symposium on Structure and Activity of Sulfided Hydroprocessing Catalysts, The Division of Petroleum Chemistry, Inc. Kansas City Meeting, Sept. 12-17, 1982. 

We have already seen some of the uses of H2 in petroleum refining. A major process is the h drogenation of heavy oil, which has a formula of approximately (CH) while gasoline has a formula of approximately (CH2)/,. Therefore, we can write this hydroprocessing reaction approximately as... 

From this stoichiometry we see that petroleum refinery needs about j mole of H2 for each mole of carbon in gasoline produced by hydroprocessing. 

Petroleum became the primary source of hydrocarbons for chemical feedstocks, beginning in about 1850 with the discovery of easily extracted cmde oil in eastern Pennsylvania and in the Ural mountains of Russia. The gases from the primary distillation of cmde oil and the light products from FCC, catalyticfreforming, and hydroprocessing are ideal mixtures of C2 to Cg alkanes that can be used to make many chemicals. Petroleum products are also cleaner than those from coal, producing no ash and less sulfur. 

This refinery process is used extensively to improve the quality and usefulness of petroleum products. Hydroprocessing can reduce unstable olefins to paraffins and can remove sulfer, nitrogen, and oxygen heteroatoms. Hydroprocessing also effectively reduces aromatics to naphthenes and/or paraffins. Various hydroprocessing catalysts are available for each specific hydroprocessing need. 

Also known as mercaptans, thiols possess very unpleasant odors and are most commonly found in the naphtha fraction. These low-boiling compounds typically contain from one to eight carbon atoms and can be linear, branched, or cyclic. Most thiols are removed from crude oil and petroleum products through hydroprocessing or sweetening. 

In Section IV, the kinetics and mechanisms of catalytic HDM reactions are presented. Reaction pathways and the interplay of kinetic rate processes and molecular diffusion processes are discussed and compared for demetallation of nickel and vanadium species. Model compound HDM studies are reviewed first to provide fundamental insight into the complex processes occurring with petroleum residua. The effects of feed composition, competitive reactions, and reaction conditions are discussed. Since development of an understanding of the kinetics of metal removal is important from the standpoint of catalyst lifetime, the effect of catalyst properties on reaction kinetics and on the resulting metal deposition profiles in hydroprocessing catalysts are discussed. 

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