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Related to Isomerization: alkylation, polymerization, Isomers, hydrogenation, Epimerization


A process whereby a compound is changed into an isomer; for example, conversion of butane into isobutane.



the conversion of a chemical compound into its isomer. In isomerization the carbon skeleton of a molecule can change as well as the nature of the functional groups and their positions, ring contraction or enlargement can occur, and so forth. Thus treatment of straight chain saturated (aliphatic) hydrocarbons with aluminum chloride (A1C13) yields branched chain hydrocarbons (for example, butane to isobutane):


These conversions occur when petroleum is refined (in cracking, pyrolysis, and reforming processes) and in part result in the formation of high-octane gasolines. Cyclohexanone oxime is iso-merized by acid to caprolactam, the starting material in the production of a nylon synthetic fiber (kapron):

This isomerization is a particular case of the Beckmann rearrangement. Among the other isomerization processes of practical importance are the conversion of ethylene oxide to acetaldehyde; the isomerization of o- and m-xylene to p-xylene, from which terephthalic acid is prepared by oxidation; and the conversion of hydrazobenzene into benzidine. The concept of isomerization also includes the interconversion of geometric isomers, for example, maleic (I) acid and fumaric (II) acid:

as well as numerous cases of racemization.


References in periodicals archive ?
Facilities operated there include the largest butane isomerization complex in the United States.
DiNardo noted that two facilities, an ethane plant and isomerization plant, will benefit from the relationship with Koch Hydrocarbon because the plants were not in full-time operation.
About 375 employees of Jacobs and its JE Merit Constructors subsidiary were involved in turnaround work at a separate unit close to the isomerization unit where the explosion occurred.
Its office in Haarlem, The Netherlands, in cooperation with its Polish partners -- Prosynchem and Prochem -- will manage the design, procurement and construction of various units, including the hydrocracker, hydrogen plant, sulfur plant, isomerization unit and reformer.
The fatalities are all contractors who were involved in maintenance work when the explosion occurred in the nearby Isomerization Unit, causing a large fire.
The two companies joined forces in early 1992 to win a $40 million contract from Petroleos Mexicanos (PEMEX) for an isomerization facility, which improves the octane rating of gasoline, at PEMEX's La Cangrejera complex near Vera Cruz, Mexico.
The refinery processes approximately 100,000 barrels per day of crude oil and other inputs, and uses advanced processing units including coking, cracking, isomerization, alkylation and reforming.
The initial project includes a 12,000 barrels per day (BPD) Penhex isomerization unit and a 46,000 BPD Naphtha Splitter to improve octane.
ExxonMobil installed its XyMax(sm) xylene isomerization technology at its Baytown Chemical Plant paraxylene feed unit.
The changes were consistent with heat-induced isomerization reactions.
on July 29, 2014, a fire was reported at the Coffeyville refinery's isomerization unit.