Heteropoly acid precursor to a catalyst for dibenzothiophene hydrodesulfurization

Abstract

A silica-supported monometallic tungstophosphoric heteropoly acid (HPA), H 3PW 12O 40, is a novel and efficient catalyst for the hydrodesulfurization of dibenzothiophene (DBT). Over a 30 wt.% HPA/SiO 2 catalyst in a trickle bed flow reactor at industrially relevant gas and liquid space velocities (GHSV 600 h −1 and LHSV 6 h −1) and an H 2 pressure of 30 bar, the hydrodesulfurization proceeds with a DBT conversion of 58% at 290°C and 80% at 350°C. These values are comparable to the performance of the industrial Co–Mo/Al 2O 3 catalyst. No loss of catalytic activity was observed for a period of 56 h. 31P MAS NMR and thermogravimetric analysis (TGA) data show that the HPA decomposes upon interaction with H 2S/H 2 to yield the active hydrodesulfurization catalyst.