催化汽油脱硫改质新技术进展

New technology progress of desulfurization for FCC gasoline upgrading

简要介绍了汽油质量升级发展历程,比较了目前为适应国Ⅴ汽油标准所采用的各种脱硫技术。依据节能环保理念和汽油升级发展需要,预测了国Ⅵ汽油标准制定的技术思路为:限硫禁锰,优化控制烯烃、芳烃含量及T_(50)温度。国Ⅵ汽油标准将可能把汽油硫质量分数由不大于10μg/g降低到不大于7μg/g;锰质量浓度由不大于2 mg/L降低到检不出;烯烃和芳烃体积分数分别由不大于24%和不大于40%降低到不大于18%和不大于35%;T_(50)馏出温度将从120℃降低到不大于110℃;苯体积分数1%要降低但难以明确降低值;汽油中异构烃的组分要大大增加。根据不同原料催化汽油中脱硫前含硫化合物类型分布以及S Zorb吸附脱硫前后汽油中硫组成数据,若要进一步降低硫化物含量,关键是要提高对烷基噻吩硫的脱除率。为适应国Ⅵ汽油标准发展要求,各种脱硫改质技术将竞相发展,包括多级吸附脱硫、多级催化加氢脱硫、脱硫脱苯保烯留芳的抽提技术、加氢脱硫异构芳构技术、醚化-异构芳构化-加氢脱硫组合技术等。在催化汽油脱硫改质技术的发展趋势中,预计醚化-异构芳构化-加氢脱硫组合工艺将是最具竞争力的技术。

The development process of gasoline upgrading is introduced,and the various desulfurization technologies for the production of Guo Ⅴ standard gasoline are analyzed and compared. Based upon the requirements of environmental protection and gasoline upgrading,it is predicted that the technical concepts for the production of Guo Ⅵ standard gasoline are： S and Mn are limited,contents of olefin,aromatics and T_（50） temperature are controlled,sulfur is reduced to ≤7 μg / g from ≤10 μg / g and Mn is decreased from 0. 002 g / L to that undetectable,olefin and aromatics are reduced to ≤18% and ≤35% from ≤24% and ≤40%respectively,T_（50） temperature is lowered to 120 ℃ from ≤110 ℃,the 1% benzene content must be reduced but it is difficult to clearly define the value,and the isometric hydrocarbons in gasoline must be greatly increased. In addition,according to the distribution of types of sulfur compounds in catalytic gasoline from different feedstocks as well as gasoline sulfur composition data before and after S Zorb adsorption desulfurization,it is pointed out that it is critical to improve the alkyl thiophenic sulfur removal. To meet the development requirements of the Guo Ⅵ gasoline standard,all kinds of desulfurization and quality upgrading processes and technologies will see a great competitive development,including multistage adsorption desulfurization technology,multistage catalytic hydrodesulfurization technology,extraction technology for the desulfurization-debenzolization and retaining olefins and / or aromatics,and combination process of the hydrodesulfurization-etherification-isomerization and aromatization. The integrated hydrodesulfurization-etherification-isomerization and aromatization technology will be the most competitive technology for FCC gasoline desulfurization and upgrading.