A facile synthesis of mesoporous Mo-Al oxides for desulfurization of dibenzothiophene in the extractive catalytic oxidative desulfurization system

In order to obtain the deep desulfurization in the extractive catalytic oxidative desulfurization (ECODS) system, the evaporation-induced self-assembly (EISA) assisted by cash (combined assembly by soft and hard chemistry) method was applied to prepare mesoporous Mo-Al oxides with the stable catalytic performance when the acetonitrile as the extractant and H2O2 as the oxidant. Their physical chemical properties were also characterized by XRD, N-2 sorption, FT-IR, SEM-EDX, H-2-TPR, and Raman techniques. The characterization results indicated that tetrahedral molybdenum species can be highly dispersed into the meso-structure of gamma-Al2O3, and the stronger interactions would be formed for 25Mo-Al catalyst than the 25Mo-Al-C catalyst prepared by impregnation method resulting in their superior physical chemical properties although the molybdenum species is the same. The 25Mo-Al catalyst showed higher desulfurization ratio than other xMo-Al catalysts and its value can be reached up to 100% at the molar ratio of H2O2 to dibenzothiophene (DBT) 2.3, volume ratio of oil phase to acetonitrile 3, catalyst dosage 0.012 g/mL, reaction temperature 60 degrees C and reaction time 30 min. The 25Mo-Al catalyst also showed good stability even after reaction for 10 recycles.