The Research Of Unsupported Catalyst For Distillate Oil Hydrorefining

Hydrorefining technology as one of the important processes for clean diesel production, has the technology advantage that can meet the requirements of lower sulfur, lower nitrogen and lower aromatics clean diesel production, has a broad development prospect. Catalytic materials, active phase of FCC diesel hydrorefining catalyst and hydrogenation reaction influence factors were studied systematically in this thesis. Hydrorefining catalyst was developed. hydrorefining catalyst is a new type high activity unsupported catalyst of W-Mo-Ni system, as well as hydrogenation operating conditions were investigated systematically.Unsupported catalyst precursor was prepared by coprecipitation method, then unsupported catalyst was prepared by adding binder. The influence of temperature and time of coprecipitation reaction, metal ratio and precipitator on the precursor properties were examined in detail. Precursor and catalyst were systematically characterized by using XRD, IR-Py, TG-DTA, SEM-EDS, TPR, HRTEM and N2 adsorption-desorption isotherms techniques, and unsupported catalyst was evaluated using model reactant and FCC diesel as feedstocks. Test results revealed that compared with conventional hydrorefining catalyst, the sulfided active phase of unsupported catalyst which displayed multi-layered bending stacking structures, has more TypeⅡa ctive sites amount. It's relative volume activity is twice that of conventional hydrorefining catalyst, as the same time sulfur and nitrogen content of hydrogenation products were less than 1μg/g.