Topic 4.1. The Role Carbocations and Carbonium Ions in Petroleum Processing

Topic 4.1. The Role Carbocations and Carbonium Ions in Petroleum Processing 

A possible replacement for MTBE is the mixture of branched Cj hydrocarbons prepared by dimerization of C4 compounds.This is economically attractive since the C4 compounds are by-products of other stages of petroleum refining. Isobutane and isobutene react with strong acid to give Cg products. The reaction involves intermolecular hydride transfers. 

The same kind of product can be obtained by acid-catalyzed dimerization of isobutene, followed by hydrogenation. 

The hydrocarbon mixtures formed by these processes have octane numbers ranging from 90 to 95. 

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