Preparation of Deep Hydrodesulfurzation Catalysts for Diesel Fuel using Organic Matrix Decomposition Method

Abstract

In this work, a series of supported CoMo or NiMo HDS catalysts have been prepared based on the organic-metal matrix decomposition method and tested for diesel deep HDS with minimum hydrogen consumption under relatively low hydrogen partial pressure conditions. The aim is to develop a HDS catalyst which can reduce sulphur in diesel fuel from 5000ppm down to 50 ppm in a single pass with minimum hydrogen consumption under the conditions of 340oC, 35 bar, LHSV 1.2 h-1 with low H2/oil ratio. The catalysts preparation process was monitored and the resultant catalyst samples before and after the HDS performance test have been characterised, some interesting results have been obtained. The presence of citric acid as organic additive/dispersing agent/chelating agent in the impregnation solution improved HDS activity compared to the equivalent CoMo catalyst prepared without citric acid, The order of activity of the cobalt precursors is Co citrate > Co acetate > Co nitrate.