The modification of zinc tungstate by doping rare earth elements is an effective way to improve its luminescent properties.
In life, silver-nickel contact materials are widely used in relays, circuit breakers for low current ratings because of their good ductility and low contact resistance.
The contradiction between the increase of organic nitrides and sulfides in oil and the heavy crude oil.
With the continuous strengthening of human environmental awareness, the quality of living environment has aroused widespread concern.
All countries have formulated strict standards for the quality indicators of sulfur, nitrogen and other harmful substances in petroleum products. The clean production process and green products have become the mainstream trend in the development of petroleum refining and chemical production. In recent years, the transition metal nitrides hydrotreating catalyst has become a hot topic in the field of new catalysts because of its excellent deep hydrodesulfurization, denitrification activity and selectivity.
Some scholars believe that the current research on oil desulfurization catalyst is too focused on the cobalt molybdenum series earlier, and has excellent mechanical and thermal stability and anti poisoning characteristics of nickel tungsten catalysts study less, but in fact, the nickel tungsten nitrogen catalyst has more potential applications.
By using temperature programmed reduction technology and r-Al2O3 as carrier, the nickel tungsten hydrofining catalyst NiWN/r-Al2O3 with different metal loading was prepared by impregnation method, and its hydrodesulfurization test was carried out.
The size of the desulfurization activity level and surface acidity of catalyst was correspondence, namely catalyst surface acidity high desulfurization activity of catalyst, desulfurization activity of small low surface acidity. The surface acidity of catalysts, in addition to direct hydrogenolysis and hydrogenation desulfurization desulfurization, isomerization and cracking degree of strengthening, for deep desulfurization, and high desulfurization activity. The test found in NiWN/r-Al2O3 than the surface of the product is 149.5, surface acidity was 0.205, in the process of cracking gasoline showed good catalytic performance, surface acidity of benzothiophene on two is enough to produce catalytic desulfurization effect, the desulfurization rate is only about 91.2%. In this regard, scholars believe that nickel tungsten nitrogen catalyst can be used for catalytic desulfurization of oil, but there is still room for improvement and improvement.
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