复合分子筛催化剂在正十六烷临氢异构化反应中协同作用的研究

选用SAPO-11分子筛和不同硅铝比的β分子筛,制备了一系列单一分子筛和复合分子筛催化剂。以正十六烷为模型化合物,对催化剂的异构化反应活性和选择性进行对比。结果表明,将硅铝比为700的β分子筛与SAPO-11复合后,复合分子筛催化剂的多支链异构烃收率明显增加,并且随着反应温度的升高,异构烃收率仍可以保持在较高的水平。BET,XRD,NH3-TPD及吡啶吸附的红外光谱表征结果表明,复合分子筛中两分子筛酸性的相对强弱影响协同作用的发挥。

STUDY ON THE SYNERGETIC EFFECT OF COMPOSITE MOLECULAR SIEVE CATALYSTS IN HEXADECANE HYDROISOMERIZATION

Using medium pore molecular sieve SAPO-11 and large pore zeolite β having various Si/Al ratios as active components, a series of catalysts containing composite molecular sieve or single molecular sieve were prepared. The catalysts were characterized by BET, XRD, NH3-TPD and FT-IR techniques. The hydroisomerization activity and selectivity of the catalyst were studied and compared using hexadecane as model compound. Test results showed that catalyst containing β(700) and SAPO-11 composite molecular sieve exhibited good hydroisomerization performance, the yield of multi-branched chain isohydrocanbons increased significantly and the isohydrocanbon yield could keep relatively high with the increase of reaction temperature. The characterization results showed that not only the types of molecular sieve but also the relative acidities of the molecular sieves could have a synergetic effect on catalyst.