Many researchers have performed typical catalytic hydrogenation of 1-methylnaphthalene to 1-methyltetrahydronaphthalene and 5-methylhydronaphthalene. The results show that the hydrogenation conversion rate of nanometer molybdenum disulfide is 5 times that of micron molybdenum disulfide at 350℃ using the same amount of micron (about 26 μm) molybdenum disulfide and 40nm molybdenum disulfide catalyst. The ratio of 1- methyltetraphthalene and 5- methyltetraphthalene in hydrogenated products was almost constant. The catalytic hydrogenation of naphthalene methylbenzyl showed that the activity of nano-molybdenum disulfide on C-C bond cleavage and aromatic ring hydrogenation was much higher than that of micron molybdenum disulfide. The hydrodesulfurization test of p-dibenthiophene showed that nanometer molybdenum disulfide had higher activity and better selectivity than micron molybdenum disulfide.
The catalytic activity of nanometer molybdenum disulfide hydrodesulfurization is higher than that of micron molybdenum disulfide mainly due to the difference in crystal structure and morphology between nanometer molybdenum disulfide and micron molybdenum disulfide. The results show that the main catalytic activity of molybdenum disulfide occurs on the crystal edge surface, while the layered molybdenum disulfide base surface has almost no hydrogenation activity. The catalytic hydrogenation activity and hydrodesulfurization activity mainly occurred at the molybdenum site of molybdenum disulfide rather than at the sulfur site. The research reveals that nano molybdenum disulphide will have a wide application prospect in the field of hydrodesulfurization, hydrodenitrification in petroleum refining, various chemical industry, synthetic chemical industry, coal liquefaction industry, high pressure synthetic diamond and other fields.
Nanometer molybdenum disulfide due to small particle size, larger than the surface, filling ability is strong, can also be used as lubricants, lubricating grease antifriction agent, anti-wear agent and extreme pressure agent. The tribological properties of nanometer molybdenum disulfide combined with dialkyl dithiophosphate have been tested and some results have been obtained. Using chemical vapor phase method or physical deposition method, such as molybdenum pentachloride reaction with hydrogen sulfide or molybdenum pentachloride reaction with sulfur will deposit nanometer molybdenum disulfide in cutting tools, deep drawing mechanical parts, drilling head, especially the molybdenum disulfide deposition on the hard TiN coating of these parts can improve the machining efficiency of cutting tools, drilling tools, broach, this kind of CVD coating has a broad application prospect.
