Study On Preparation Of AgY Zeolites And Its Adsorptive Desulfurization Performance

The adsorptive desulfurization technology of AgY zeolite were researched in this article. The effects of different factors on the desulfurization were studied and proper desulfurization conditions were found out. At the same time the competition adsorptive of nitrogen compounds and aromatic compound were studied and the adsorptive desulfurization process kinetic model had a prelinibary exploration.The experiment of adsorptive desulfurization, AgYIE zeolite was prepared by ion exchange method. The effects of different factors on desulfurization with the thiophene/petroleumether model oil as feedstock were investigated. The result shows that the AgY zeolite with AgNO3 solution concentration of 0.25 mol/L and dosage of 20 mL, ion exchange time of 24 h and calcination temperature of 500℃exhibited the best desulfurization performance. Under the conditions of thiophene/petroleumether model oil 10 mL, adsorbents 0.2 g, adsorptive temperature 40℃, adsorptive time 30 min, the highest desulfurization rate is 93.81% and the static saturated equilibrium sulfur adsorption capacity was 0.8523 mmol/g. The dynamic saturated adsorption capacities of AgY zeolite was 1.2188 mmol/g at ambient temperature and pressure. Kinetics of adsorptive desulfurization over AgY zeolites meet the pesudo-second order model with the equilibrium adsorption capacity q2=181.83 mg/g and the initial adsorption rate k2=0.015 g/(mg·min). The competition absorptive of nitrogen compounds and aromatic compound have greet influence on absorptive desulfurization and nitrogen compounds has more influence than aromatic compound.The experiment of adsorptive desulfurization, AgYMW zeolite was prepared by microwave assist ion exchange method. The effects of different factors on desulfurization with the thiophene/petroleumether model oil as feedstock were investigated. The result shows that the AgY zeolite with AgNO3 solution concentration of 0.2 mol/L, microwave power of 240 W, microwave irradiation time of 20 min as well as calcined at 500℃was found to be optimal. Under the conditions of thiophene/petroleumether model oil 10 ml, adsorbents 0.2 g, adsorptive temperature 40℃, adsorptive time 30 min, the highest desulfurization rate is 90.28% and the static saturated equilibrium sulfur adsorption capacity was 0.7970 mmol/g. The dynamic saturated adsorption capacities of AgY zeolite was 1.0938 mmol/g at ambient temperature and pressure. Kinetics of adsorptive desulfurization over AgY zeolites meet the pesudo-second order model with the equilibrium adsorption capacity q2=170.03 mg/g and the initial adsorption rate k2=0.018 g/(mg·min). The competition absorptive of nitrogen compounds and aromatic compound have greet influence on absorptive desulfurization and nitrogen compounds has more influence than aromatic compound.