生产低硫汽油的新型催化裂化工艺研究

Research on Novel FCC Technology for Reducing Sulfur Content in Gasoline

通过调变催化剂中V的价态,借助X射线光电子能谱(XPS)分析、小型固定床和中型提升管装置实验,开发了以自制催化剂c为基础、再生斜管部分增加H_2还原预处理器的催化裂化(FCC)新工艺。催化剂经H_2还原预处理后,其所含V由5价态降为4价、3价,甚至更低价态,在催化反应中可与氧化态硫接触反应,从而降低FCC汽油硫含量。经H_2还原预处理的自制催化剂c(V质量分数0.6%)的催化脱硫效果显著,适宜的H_2预还原温度为550℃,预还原时间为20 min。采用自制催化剂c,在H_2预还原温度650℃、还原时间20 min、H_2流量40 L/h、反应温度500℃、再生温度690℃、剂/油质量比6的条件下,新工艺的FCC汽油S质量浓度由880μg/mL降至515μg/mL。

The performance of novel FCC technology for reducing sulfur content in gasoline was developed on the investigation of XPS spectroscopy and the experiments in a fixed bed and a riser pilot plant unit. The developed novel FCC technology included the use of self-prepared catalyst c and the equipment of H2 reduction pretreatment part in the regenerated catalyst line of FCC unit. The V element in FCC catalyst was reduced to low valence state after H2 reduction pretreatment, which could react with sulfur of catalytic oxidation state during the catalytic reaction, resulting in the reduction of the sulfur content in FCC gasoline. The optimal conditions for catalyst c （vanadium mass fraction is 0.6%） were the hydrogen reduction pretreatment temperature of 550℃, space time of 20 rain. With the novel FCC technology and catalyst c, under the H2 reduction pretreatment temperature and space time of 650℃ and 20 min, H2 flow rate of 40 L/h, reaction temperature of 500℃, regeneration temperature of 690℃, catalyst to oil ratio of 6, the sulfur mass concentration of gasoline decreased from 880 tLg/mL to 515 ug/mL.