Aluminum phosphate as active matrix of fluid catalytic cracking catalysts: Y zeolite stabilization

Abstract The development of new matrices can improve the hydrothermal stability of fluid catalytic cracking catalysts and provide better selectivity to cracking products. Amorphous, mesoporous and stoichiometric aluminum phosphate (AlPO4) was investigated as active matrix to achieve these purposes. In its gel form, the material was initially added to ultra-stabilized Y zeolite to generate composites with mass ratio of about 1:1. The interaction between AlPO4 and Y zeolite avoided AlPO4 crystallization during steaming and increased framework aluminum retention, preserving more Bronsted acid sites. A spray-dried catalyst containing AlPO4 was steam deactivated and tested by vacuum gas oil cracking, being compared with an alumina-containing catalyst and a reference without active matrix. AlPO4-containing catalyst presented tolerance to contaminant metals, higher selectivity to naphtha yields and exhibited a higher hydrogen transfer reaction rate, leading to the increase in isoparaffins and aromatics yields and the increase in the motor octane number in the cracked naphtha.