Patent ID: 6294498
Filing Date: 2001-09-25
Classification: B01J,C10G

Abstract:
A process comprising:a) providing an inert coating material capable of functioning as a protective layer against oxygen and water and also being removable during refining or a hydrocarbon conversion reaction;b) applying said coating material on heterogeneous porous hydrocarbon conversion catalyst particles, said catalyst comprising a support and a pair of catalyst metals selected from the group consisting of CoMo, NiMo and NiW under conditions wherein the coating material is present in a quantity corresponding to less than about half of the catalyst pore volume;c) wherein said coating material is1. atomized or dispersed on the catalyst by continuously stirring the catalyst and keeping it at a temperature that is below the crystallization point of the coating material, or2. a solution that contains the material is atomized, sprayed or dispersed by continuously stirring the catalyst at a temperature that is above the boiling point of the solvent of said solution; andd) wherein the coating on the particle exhibits a concentration gradient which decreases from the periphery of the particle towards the center of the particle.