One-step Synthesis of Methanethiol with Mixture Gases (CO/H2S/H2) over SBA-15 Supported Mo-based Catalysts

Kn-Mo/SBA-15 catalysts prepared via incipient-wetness impregnation by using K2CO3 and (NH4)6Mo7O24
• 4H2O as precursors were tested for synthesizing CH3SH with mixture gases (CO/H2S/H2) and the parameters of pretreatment and reaction conditions were investigated in detail. After pretreatment under the optimal conditions (reduction temperature of 400 oC, vulcanization temperature of 280 oC and vulcanization time of 6 h), Kn-Mo/SBA-15 catalysts exhibit a highest performances for CH3SH synthesis at reaction conditions of CO/H2S/H2=1/1/2, 0.2 MPa, 1000 h-1 and 300 oC. It was found that the optimal K/Mo molar ratio of Kn-Mo/SBA-15 is 2.0. On the basis of H2-TPR and XRD characterization results, it can be concluded that the addition of K would lead to the transformation of Mo6+ from octahedral Mo (Oh) into tetrahedron Mo (Td). The promoting effect of K was achieved by interaction between K and Mo species to form the single molybdenum K2MoO4, which is beneficial to the formation of CH3SH.