Molybdenum oxide catalysts for metathesis of higher 1-alkenes via supporting MoO2(acetylacetonate)2 and MoO2(glycolate)2 on SBA-15 mesoporous molecular sieves

摘要

New heterogeneous catalysts for alkene metathesis were prepared by immobilization of molybdenum dioxide bis(acetylacetonate) and molybdenum dioxide bis(glycolate) on mesoporous molecular sieve SBA-15. Thermal spreading (TS) method and wet impregnation (WI) followed by calcinations were employed as synthesis approaches. These new catalysts represent inexpensive, easy-to-prepare and highly active and selective heterogeneous catalysts for metathesis of higher linear 1 -alkenes applicable under mild reaction conditions without the necessity of solvent or co-catalyst in the reaction mixture. In metathesis of 1-octene, these catalysts showed up to four times higher activity compared with MoO3 supported on conventional silica as well as on SBA-15. This is probably due to the better dispersion of the molybdenum oxide phase on the mesoporous support surface. In metathesis of 1-dodecene and 1-tetradecene these catalysts based on SBA-15 exhibited a significantly higher activity than corresponding catalysts on MCM-41, probably due to the larger pores.