Comparison of the iso-structural H-SAPO-37 and H-faujasite as catalysts for the isobutane/2-butene alkylation

doi:10.1016/0926-860X(96)00113-5

Applied Catalysis A: General

Volume 144, Issues 1–2, 2 September 1996, Pages 305-317

https://doi.org/10.1016/0926-860X(96)00113-5 Get rights and content

Abstract

The alkylation of isobutane with 2-butene has been studied in a slurry reactor on the iso-structural H-SAPO-37 and dealuminated faujasite (FAU) catalysts. It was found that mainly dimerization takes place on H-SAPO-37 by producing C₈ olefins. In the small fraction of C₈ paraffins, the 3,4-dimethylhexane (3,4 DMH) was the most abundant compound. The dealuminated H-FAU catalyst, on the other hand, produced mainly the desired trimethylpentanes (TMPs). The number and strength of the acid sites in H-SAPO-37 and dealuminated H-FAU were investigated by NH₃-TPD and IR spectroscopy, revealing a considerably higher relative concentration of strong acid sites in the dealuminated H-FAU catalyst compared to H-SAPO-37. Using the ratio of pyridine adsorbed at 400°C and 250°C as a measure of the ratio of strong to weak acid sites in the samples, ratios of 0.40 and 0.65 were obtained for the H-SAPO-37 and dealuminated H-FAU, respectively, ranking the dealuminated H-FAU as a much better catalyst than H-SAPO-37 in the isobutane/2-butene alkylation reaction.

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Comparison of the iso-structural H-SAPO-37 and H-faujasite as catalysts for the isobutane/2-butene alkylation

Abstract

Zeolites

Appl. Catal. A

Appl. Catal. A: General

Zeolites

J. Catal.

Microporous Mater.

J. Catal.

Catal. Rev.