不同硅/铝比La/ZSM-5分子筛对催化裂化轻汽油异构化/芳构化性能的影响  

Effect of La/ZSM-5 Zeolites With Different SiO_(2)/Al_(2)O_(3) Ratios on the Isomerization/Aromatization Performance of FCC Light Gasoline

作　　者：宋绍彤 李天舒 鞠雅娜 李阳 吴培 孙长宇[1] 段爱军[1] SONG Shaotong;LI Tianshu;JU Ya′na;LI Yang;WU Pei;SUN Changyu;DUAN Aijun(State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing 102249,China;Petrochemical Research Institute,CNPC,Beijing 102206,China)

机构地区：[1]中国石油大学(北京)重质油国家重点实验室,北京102249 [2]中国石油石油化工研究院,北京102206

出　　处：《石油学报（石油加工）》2022年第3期553-563,共11页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家重点研发计划项目(2019YFC1907602)基金资助。

摘　　要：分别以硅/铝摩尔比为40、200、300、400的ZSM-5分子筛为载体,以金属镧为活性组分,制备一系列催化裂化(FCC)轻汽油异构化/芳构化催化剂,通过X射线衍射(XRD)、N_(2)吸附-脱附、^(27)Al MAS NMR、氨气程序升温脱附(NH_(3)-TPD)、吡啶红外吸附(Py-FTIR)、扫描电镜(SEM)等手段对其进行表征。以FCC轻汽油为原料,研究了La/ZSM-5分子筛硅/铝摩尔比变化对异构化/芳构化反应性能的影响。结果表明:随着ZSM-5硅/铝摩尔比的增加,其酸强度逐渐降低,B酸与L酸酸量比值减小,芳烃产率呈现先增加后减少的趋势;当硅/铝摩尔比为200时,Bronsted(B)酸与Lewis(L)酸酸量比值最低,FCC轻汽油异构化/芳构化性能最高;在反应温度380℃、压力1.0 MPa、氢/油体积比100和体积空速1.0 h^(-1)的条件下,La/ZSM-5-200分子筛催化剂作用下异构化/芳构化产品与反应原料相比,烯烃体积分数降低32.81百分点,异构烷烃体积分数增加18.24百分点,芳烃体积分数增加到5.97%,辛烷值降低5.38个单位,达成以芳构/异构反应为主的大幅度降烯烃的目标,为京Ⅵ(B)汽油标准的实施提供了技术支持。A series of fluid catalytic cracking(FCC)light gasoline aromatization catalysts were prepared separately using ZSM-5 zeolites with different silica/alumina mole ratios(40,200,300 and 400)as the carrier and lanthanum(La)as an active component.The catalysts were characterized by means of X-ray diffraction(XRD),N_(2)adsorption and desorption,^(27)Al MAS NMR,ammonia temperature programmed desorption(NH_(3)-TPD),pyridine infrared absorption(Py-FTIR)and scanning electron microscopy(SEM).The effect of changes in the silica/alumina ratio of La/ZSM-5 zeolite on the isomerization/aromatization performance was studied using FCC light gasoline as raw material.The results show that as the silica/alumina mole ratio of ZSM-5 zeolite increases,the acid strength gradually decreases,the Bronsted/Lewis(B/L)acid amount ratio decreases,and the aromatics yield tends to increase after a decrease;when the silica/alumina mole ratio reaches 200,the B/L acid amount ratio hits the bottom and the aromatization performance of FCC light gasoline achieves the peak;at the reaction temperature of 380℃,the pressure of 1.0 MPa and the space velocity of 1.0 h^(-1),by comparing the isomerization/aromatization products under the catalyst action of La/ZSM-5-200 zeolite with the raw material,it can be found that the volume fraction of olefin reduces by 32.81 percentage,that of isoparaffin increases by 18.24 percentage,that of aromatics increases by 5.97 percentage,while octane number reduces by 5.38 percentage,which have achieved the substantially lowering of olefin mainly by aromatization/isomerization,providing technical support for the implementation of BeijingⅥ(B)gasoline fuel standard.

关 键 词：La/ZSM-5分子筛 硅/铝摩尔比 异构化 芳构化 酸性 

分 类 号：TE6[石油与天然气工程—油气加工工程]