Isooctane from isobutylene

Application Tb produce isooctane from isobutylene, based on two-step process involving catalytic dimerization followed by hydro-... 

Alkylation of isobutylene and isobutane in the presence of an acidic catalyst yields isooctane. This reaction proceeds through the same mechanism as dimerization except that during the last step, a proton is transferred from a surrounding alkane instead of one being abstracted by a base. The cation thus formed bonds with the base. Alkylation of aromatics with butylenes is another addition reaction and follows the same general rules with regard to relative rates and product stmcture. Thus 1- and 2-butenes yield j -butyl derivatives and isobutylene yields tert-huty derivatives. 

Mixed C4 olefins (primarily iC4) are isolated from a mixed C olefin and paraffin stream. Two different liquid adsorption high-purity C olefin processes exist the C4 Olex process for producing isobutylene (iCf ) and the Sorbutene process for producing butene-1. Isobutylene has been used in alcohol synthesis and the production of methyl tert-butyl ether (MTBE) and isooctane, both of which improve octane of gasoHne. Commercial 1-butene is used in the manufacture of both hnear low-density polyethylene (LLDPE) and high-density polyethylene (HDPE)., polypropylene, polybutene, butylene oxide and the C4 solvents secondary butyl alcohol (SBA) and methyl ethyl ketone (MEK). While the C4 Olex process has been commercially demonstrated, the Sorbutene process has only been demonstrated on a pilot scale. 

NExOCTANE A process for making isooctane by dimerizing isobutylene over an acidic ion-exchange catalyst. The product is used as a gasoline additive. Developed from 1997 by Neste Engineering (a subsidiary of Fortum Oil Gas, Finland) and Kellogg Brown Root. The first commercial unit started operating in 2002. See also SP-Isoether. 

Isobutane I-so- byu- tan [ISV] (1876) (isobutylene, 2-methylpropene) n. (CH3)2 C=CH2. a colorless, highly volatile liquid or liquidified gas derived from petroleum, easily polymerized to form polybutene. It has a bp of —6.9°C a fp of —139°C, a flp of —105°C, and Sp gr of 0.6 (20°C). Uses Production of isooctane, butyl rubber, polyisobutene resins, tert-butanol, methacrylates, co-polymer resins with butadiene, and acrylonitrile. 

Sulfuric acid is used for a variety of other purposes in the chemical industry. For example, it is the usual acid catalyst for the conversion of cyclohexanone oxime to caprolactam, used for making nylon. It is used for making hydrochloric acid from salt via the Mannheim process. Much H2SO4 is used in petroleum refining, for example as a catalyst for the reaction of isobutane with isobutylene to give isooctane, a compound that raises the octane rating of gasoline (petrol). Sulfuric acid is also important in the manufacture of dyestuffs solutions and is the "acid" in lead-acid (car) batteries. 

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