High activity hydrodesulfurization catalyst, a method of making a high activity hydrodesulfurization catalyst, and a process for manufacturing an ultra-low sulfur distillate product

A method of making a catalyst composition suitable for use in the manufacture of ultra low sulfur diesel, said method comprises:

• mixing a high purity boehmite starting material comprising more than 98 percent alpha alumina monohydrate in the form of a powder with water in a weight ratio of boehmite-to-water of from 0.1:1 to 10:1, wherein said high purity boehmite starting material has impurities of less than 200 ppm silicon dioxide and less than 200 ppm iron oxide;
• forming a shaped particle from said mixture comprising at least 95 weight percent, exclusive of water, boehmite;
• calcining said shaped particle under a controlled temperature condition to convert said boehmite of said shaped particle to gamma-alumina;
• controlling said controlled temperature condition to within a calcination temperature range of from about 850° F. and 950° F. so that essentially all of said boehmite of said shaped particle is converted to gamma-alumina, with less than 5 weight percent of said boehmite of said shaped particle being converted to a crystalline transitional phase other than gamma-alumina to thereby provide a calcined shaped particle;
• impregnating said calcined shaped particle with a hydrogenation catalytic component to thereby provide an impregnated calcined shaped particle;
• and
• calcining said impregnated calcined shaped particle at a temperature of from about 880 ° F. to 990° F. to thereby provide a catalyst composition capable of desulfurizing a distillate feedstock to a sulfur concentration of less than 15 parts per million.