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Alkylation processes with strong acid catalysts are fraught with many difficulties. Problems involved are the handling of highly corrosive and costly acid and the necessity of pretreatment of alkylates aimed at removal of traces of acids, harmful sulphate esters, and some others.Accordingly the search for a novel highly active and selec tive catalyst for isoparaffin-olefin alkylation is still an objective of numerous recent patents on the subject (1).In the present paper, catalytic activity of a number of zeolitic catalysts in alkylation of isobutane with various olefins have been investigated and some considerations of ethylene alkylation have been made. ExperimentalOlefins used in the alkylation were ethylene, propylene, isobutene and 2-methyl-butene-2, all 98-99% pure; butene-1, 98% pure but containing some isobutane and traces of butene-2; and a butene-1 and -2 mixture with a component ratio of about 1:2 respectively.Isobutane had a purity of 96% with 4% of n-butane. The experiments were performed isothermally in a stainless steel tube. Optimum reaction conditions of 80-100°C, 20 atm, LHSY-1hr -1 , and an isobutane-olefin ratio of 15-20 were determined by mathematical planning of experiments and regression analysis (2).Composition of the liquid products was determined by gas chromatography, using a 100m capillary column with squalane, gas products were analyzed over vaseline oil. The catalysts were prepared by the 1on exchange of the sodium form of zeolite Y with metal cations (3).Butyl amine titration and ammonia thermodesorptlon methods were used to determine surface acidity of the catalysts. 89

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