Abstract:
Under laboratory conditions, nitrogen adsorption from the coking wax oil was studied respectively by D72 and D001-CC cationic activation resins as adsorbents in a continuous fixed bed reactor. Micro reaction system of fluid catalytic cracking unit was used to study the catalytic cracking reaction performance of coking wax oil after denitrification. Adsorption properties of two kinds of activation resin were compared by studing the adsorption breakthrough curve in the fixed bed, the dynamic adsorption properties of alkaline nitrogen compounds in the coking wax oil and the affect of the adsorption temperature on the removal rate of basic nitrogen compounds. Catalytic cracking performances of coking wax oil before and after denitrification were finally compared with catalytic cracking experiments. Results of experiments showed that the optimum adsorption temperature of D001-CC activation resin was 70℃, the adsorption capacity was saturated 6 hours later, and the saturated adsorption capacity is 19.35 mg/g. The optimum adsorption temperature of D72 activation resin was 60℃, the adsorption capacity was saturated 5 hours later, and the saturated adsorption capacity was 7.75 mg/g. The degree of catalytic cracking of coking wax oil deepened and the conversion rate improved after dealing with the resin denitrification. When the reaction temperature was 400℃, the conversion rate of coking wax oil without denitrification was 44%. The conversion rate of coking wax oil reached 81.5% after 30 minute's adsorption denitrification treatment. The influences of alkaline nitrogen content on catalyst activity were more sensitive at higher reaction temperature. The more substantially decrease of alkaline nitrogen content in the coking wax oil, the more significantly increases of catalytic cracking conversion rates.