Ni ZnO-Zn ZSM-5双功能耦合催化剂的制备及反应吸附脱硫耦合芳构化反应性能研究

PREPARATION OF Ni ZnO-Zn ZSM-5 BIFUNCTIONAL COUPLING CATALYST AND COUPLED AROMATIZATION DURING REACTIVE ADSORPTIVE DESULPHURIZATION

在催化裂化汽油深度脱硫过程中,采用传统的Ni/ZnO吸附剂存在烯烃饱和现象,造成辛烷值损失。针对上述问题,通过在Ni/ZnO吸附剂中引入Zn/ZSM-5芳构化组分,研究催化裂化汽油反应吸附脱硫耦合烯烃芳构化反应性能。采用等体积浸渍法制备了Ni/ZnO-Zn/ZSM-5双功能耦合催化剂,评价了耦合催化剂的脱硫、烯烃芳构化性能,考察了Ni含量及Ni在ZnO和Zn/ZSM-5上的分配比对其催化性能的影响。结果表明:在反应温度450℃条件下,催化剂在Ni质量分数为6%、Ni在ZnO和Zn/ZSM-5上的分配比为1∶1时的性能最优,芳构化率为38.58%,液体收率为88.33%。优化反应的温度条件,在温度为420℃时,6%Ni/ZnO-Zn/ZSM-5(1∶1)催化剂的脱硫率可达98.7%,烯烃转化率为54.0%,芳构化率为29.7%,与常规Ni/ZnO吸附剂相比,6%Ni/ZnO-Zn/ZSM-5(1∶1)催化剂作用下的辛烷值损失降低0.69。

In the process of fluid catalytic cracking(FCC)gasoline deep desulfurization,olefin saturation exists in the traditional Ni/ZnO adsorbent,which results in the loss of octane number.In order to solve this problem,reactive adsorptive desulfurization coupling olefin aromatization reaction was attempted by introducing Zn-ZSM-5 into Ni/ZnO component.Bifunctional coupled Ni/ZnO-Zn/ZSM-5 catalyst was prepared by the equal volume impregnation method,the performances of coupling catalysts for desulfurization and olefin aromatization were evaluated,and the effects of Ni content and Ni partition ratio on ZnO and Zn/ZSM-5 were investigated.The results showed that the catalyst had the best catalytic performance at a reaction temperature of 450℃when the mass fraction of Ni content was 6%and the ratio of Ni to ZnO and Zn/ZSM-5 was 1∶1.The aromatics generation rate of 38.58%and the liquid yield rate of 88.33%could be achieved.The operating temperature of the process was optimized and the regeneration performance of the catalyst was examined.At 420℃,the desulphurization rate,olefin conversion rate and aromatics generation rate of 6%Ni/ZnO-Zn/ZSM-5(1∶1)catalyst were 98.7%,54.0%and 29.7%,respectively,and the loss of octane number was reduced by 0.69 compared with that of the conventional Ni/ZnO desulphurization reaction.In addition,the process exhibited excellent desulfurization and aromatization performance in multiple regeneration cycles,demonstrating the feasibility of continuous processing.