Hexagonal mesoporous silicas with and without Zr as supports for HDS catalysts

Hexagonal mesoporous materials (HMS) with and without zirconium were used a s supports for preparation of HDS catalysts, The catalysts prepared by modi fication of the supports with 12-phosphomolybdic acid (HPMo) were character ised by nitrogen adsorption, IR spectroscopy, TPD of ammonia, TPR and catal ytic activity in thiophene hydrodesulphurisation. Parent silicas showed mes oporous structure with BET surface area between 1200 and 800 m(2) g(-1), po re size diameter around 3.3 nm and acidity around 0.3 mmol NH3 g(-1). Molyb denum catalysts possess stronger acidity than the supports used. The cataly tic activities in hydrodesulphurisation of thiophene of the molybdenum cont aining catalysts prepared with HMS were higher than the activity of the cat alyst prepared with amorphous silica. Higher acidity of Zr-HMS supports lea d to lower stability in the thiophene conversion. (C) 2001 Elsevier Science B.V. All rights reserved.