HYDROTREATING CATALYTIC FUNCTIONALITIES OF SBA-16 SUPPORTED Mo, CoMo, AND NiMo CATALYSTS

摘要

More active HDS catalysts are one of the main goals of thenmodern refining industry. Such a demanding task requires catalystsnthat are several times more active than the presently used catalysts.1nThese catalysts should have high activity as well as different activitynprofiles with respect to different functionalities. In recent years, innorder to improve the activity of hydrotreating catalysts, manynapproaches like (i) Preparation methods, (ii) Support modification andn(iii) Altering the active component have been followed. Among thesenapproaches, variation of support is an important one.2,3 Differentnsupports such as oxides, mixed oxides, zeolites, mesoporous materialsnhave been studied as supports for hydrotreating catalysts.4-10 Amongndifferent supports and their combinations, ordered mesoporous silicansuch as HMS, MCM-41 and SBA-15 has attracted considerablenattention due to their high surface area, large volume, orderednmesopores and diverse morphology. MCM-41 supported CoMo andnNiMo catalysts are reported superior activity in HDN and HDSnreactions with model compounds.11 However MCM-41 type materialsnhave poor hydrothermal stability, which represents a serious limitationnto their practical applications. SBA-15 type materials have largernpores, thicker pore walls and higher hydrothermal stability comparednto MCM-41. Purely siliceous SBA-15 has been tested as support fornFeW, NiW, CoMo and NiMo12-13 and their hydrotreating activity hasnbeen determined using model compounds such as thiophene,ndibenzothiophene and real feeds. These studies evidenced the superiornactivity of SBA-15 supported catalysts than the conventional γ-Al2O3nsupported catalysts