Alkylation of paraffins

Although the alkylation of paraffins can be carried out thermally (3), catalytic alkylation is the basis of all processes in commercial use. Early studies of catalytic alkylation led to the formulation of a proposed mechanism based on a chain of ionic reactions (4—6). The reaction steps include the formation of a light tertiary cation, the addition of the cation to an olefin to form a heavier cation, and the production of a heavier paraffin (alkylate) by a hydride transfer from a light isoparaffin. This last step generates another light tertiary cation to continue the chain. 

Commercial Alkylation of Paraffins and Aromatics Edwin K. Jones The Reactivity of Oxide Surfaces E. R. S. Winter... 

Commercial Alkylation of Paraffins and Aromatics Edwin K. Jones... 

Aluminum chloride is used in the petroleum industries and various aspects of organic chemistry technology. For example, aluminum chloride is a catalyst in the alkylation of paraffins and aromatic hydrocarbons by olefins and also in the formation of complex ketones, aldehydes, and carboxylic acid derivatives. 

Putney, D. H., "Sulfuric Acid Alkylation of Paraffins", Advances in Petroleum Chemistry and Refining, Interscience, (1959), pp. 315-355. 

OTHER COMMENTS used as a catalyst in the petroleum industry (in the alkylation of paraffins) used in fluorination processes, as in the aluminum industry used in the manufacture of fluorides used for separating isotopes of uranium used in dye chemistry. 

Olefin Alkylation of Paraffins. Reactions involving parafiSns and olefins may be represented as follows ... 

The formation of these by-products is apparently due in part to further reaction of the primary products by dissociation into new paraffins and olefins and the subsequent reaction of these olefins with the original isoparaffin (as well as of the new paraffins with original olefin). Such reactions, which may be termed destructive alkylation, are similar to those which have been suggested to account for the products of the autodestructive alkylation of paraffins (Ipatieff and Grosse, 23). 

No detailed discussion of the use of aluminum bromide as catalyst for the alkylation of paraffins with olefins has been published. Alkylation presumably takes place in much the same manner as with aluminum chloride, the chief difference being that the catalyst is soluble in the paraffin. 

It should be remembered that the above reaction is also the first step in the mechanism for the alkylation of paraffins by olefins as proposed by Schmerling (9). As a matter of fact, the mechanism proposed by Schmerling for the alkylation reaction applies equally well, in reverse, for the mechanism of catalytic cracking of paraffins. 

The mechanisms of fast processes, during polymer synthesis, are the same for all low molecular weight (MW) compounds, including the chlorination and hydrochlorination of ethylene, sulfuric acid alkylation of paraffins by olefins, neutralisation of acid and alkali media, and so on. Thus, the formation of different macroscopic types, during fast chemical reactions, is a common phenomenon which can be observed in almost all fast chemical processes, including the interaction of low MW compounds. 

Ipatieff Alkylation of paraffins with superacid catalysts (commercialized for the production of kerosene in 1942)... 

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