HDS & deep HDS activity of Co/Mo/S-mesostructured synthetic clays

The HDS and deep HDS activity of Co/Mo/S-mesostructured synthetic clays was studied. For HDS, the conversion of dibenzothiophene (DBT) to biphenyl was examined at 400°C using Co/Mo/S-loaded mesostructured clay supports. Activity was compared to a Crosfield 465 commercial catalyst. No hydrogenation was observed with any of the clay supports. The most active clay was derived from ludox silica sol AS-30, with an activity of 65% DBT conversion (86% for Crosfield 465). For deep HDS, the conversion of 4,6-dimethyldibenzothiophene was tested at 325° and 350°C and compared to a Criterion 344 commercial catalyst. At 325°C, Cr344 displayed 11.4% conversion. This value was nearly attained for the Co/Mo/S-loaded mesostructured clay derived from AM30 silica sol (10.5%). The commercially available synthetic hectorite called Laponite had very low activity (3%), indicating that the unique morphology of the mesostructured clays is important. Hydrogenolysis vs. hydrogenation pathways were compared for the deep HDS reaction. This is an abstract of a paper presented at the ACS Fuel Chemistry Meeting (San Diego, CA Spring 2005).