Catalysts based on molybdenum and tungsten heteropoly compounds for the hydrotreatment of oil fractions

Abstract

The results from 15 years of studies performed at the Samara State Technical University in the field of developing highly active sulfide catalysts for the hydrotreatment of straight-run and refractory low-grade oil fractions with the use of molybdenum and tungsten heteropoly compounds (HPCs) as precursors are presented. A wide range of HPCs with Anderson and Keggin structures is studied in the synthesis of sulfide catalysts. The order of activities in the hydrodesulfurization of sulfur compounds and the hydrogenation of unsaturated hydrocarbons are established for the heteroelements incorporated into HPCs. Catalytic activity—HPC heteroatom electronegativity correlations are revealed. Special attention is given to controlling the selectivity of catalysts with respect to parallel hydrogenation and hydrodesulfurization reactions. A wide variety of highly active sulfide catalysts for the hydrotreatment of diesel fuel, catalytic cracking gasoline, vacuum gas oil, and lube feedstocks is developed. The techniques for their synthesis and activation (sulfidation) are substantiated. The developments are patented and are close to being introduced at oil refineries whenever they are ready.