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A process whereby a compound is changed into an isomer; for example, conversion of butane into isobutane.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



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.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Isomerization of C4 streams produces a more desirable feedstock for alkylation units such as KBR's Solid Acid Alkylation Technology (K-SAAT).
The isomerization tests have been performed keeping the samples for 60 min at a constant temperature ranging from 210 to 260[degrees]C, on monomers and on polymers obtained by melt polycondensation in our previous work [4] (Fig.
In this connection, isomerization (also known as rearrangement process) is the process in which one isomer is transformed to another isomer having identical composition and molecular weight but different geometrical arrangement of molecules.
Until recently, this kinetic analysis has rarely been used because of the complexity of kinetic models that describe the possibilities of simultaneous binding and isomerization steps for two ligands.
Thermal degradation and Isomerization Kinetics of Triolein studied by Infrared Spectrometry and GC-MS combined with Chemometrics.
Moreover, at 328 K lisinopril was eluted as a narrow single peak due to the high isomerization rate of the two isomers.
It was analyzed that one-dimensional PESs with respect to the main twist of phenyl groups around the central C=C bond reflect the main dynamical effect for isomerization at OBF-CI as mentioned above.
Essar Oil has also commissioned a new Isomerization Unit at Vadinar, giving the refinery the ability to produce gasoline with a high octane rating and almost zero sulphur content the company stated.
The research team, led by a Syracuse University physicist, has demonstrated that visual signals can be initiated in the absence of isomerization.
The fire occurred in an NGL storage area away from the main part of the MTBV complex that houses Enterprise's NGL and propylene fractionators, butane isomerization units and other processing facilities, none of which were damaged by the fire.
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