Effect of the nature of zeolite and modifying additives on the activity of zeolite-containing catalysts in n-butane isomerization

Article abstract of DOI:10.1007/BF02495288

Isomerization of n-butane on various types of zeolites (ZVM, ZVK, mordenite, and Y) modified with transition metals and cationic and anionic additives was investigated. Under the conditions studied, H-forms of zeolites are inactive. Pt-containing systems based on the H-form of ZVM (HZVM) are the most efficient catalysts for n-butane isomerization, and the yield of isobutane reaches 20-26 wt.% at a selectivity of 40-45%. Modification of this catalyst with Ga and Fe compounds or with an aqueous solution of HCl increases the selectivity with respect to isobutane up to 70-90%. Introduction of Zn²⁺ cations or F^- and SO₄^2- anions into the Pt-containing HZVM system decreases the selectivity and yield of isobutane due to the formation of very strong acidic centers on which disproportionation and hydrocracking of n-butane mainly occur.