Method of preparation of ex situ selectivated zeolite catalysts for enhanced shape selective applications and methods to increase the activity thereof

摘要

A method of preparing a modified catalytic molecular sieve for enhanced shape selective hydrocarbon conversions in which a catalytic molecular sieve is modified by being exposed to at least one ex situ selectivation sequence, each sequence including an impregnation of the molecular sieve with a selectivating agent in an aqueous emulsion and a subsequent calcination of the impregnated molecular sieve. The selectivating agent compositions for the ex situ selectivation method are also described, including the selectivating agents, the surfactants, and the aqueous components. Also, a method for moderate steaming of the ex situ selectivated molecular sieve. Also a method for in situ trim- selectivating the ex situ selectivated catalytic molecular sieve. Also described is the modified catalytic molecular sieve modified by this method. Also described is a process for shape selective hydrocarbon conversion comprising contacting a hydrocarbon feedstream under conversion conditions with the modified catalytic molecular sieve.