Highly active dispersed MoS2 catalyst prepared by hydrothermal synthesis for hydrodesulfurization of 4,6-dimethyldibenzothiophene

This presentation discusses the development of highly active dispersed molybdenum sulfide MoS2-based catalysts for hydrodesulfurization. In an exploratory study in our early work, we found that water addition has a dramatic promoting effect on coal liquefaction using ammonium tetrathiomolybdate [Song et al., Energy & Fuels, 1995; Fuel, 2000]. In the efforts to understand the origin of such promoting effects, we found that with a suitable amount of water, highly active catalyst particles are generated in-situ [Yoneyama and Song, Catalysis Today, 1999; Energy & Fuels, 2002]. Further study in our recent work reveal that highly dispersed, nano-sized MoS2 particles with lower level of stacking (as examined by TEM and XRD) and higher surface area is produced in the presence of water and an organic solvent under hydrogen, which shows higher catalytic activity towards HDS of 4,6-dimethyldibenzothiophene (4,6-DMDBT) in the presence of the unsubstituted dibenzothiophene (DBT). The higher conversion of 4,6-DMDBT compared with that of DBT in the simultaneous HDS indicates that novel catalysts can be developed which promote the conversion of the more refractory sulfur compounds that are more difficult to desulfurize with the conventional hydrotreating catalysts.