锌改性HZSM-5催化正构烷烃临氢芳构化性能

采用等体积浸渍法制备不同ZnO负载量的Zn/HZSM-5系列催化剂，采用BET、XRD、TPD和Py-IR等方法对所制备催化剂表征分析；在5 mL固定床小型反应装置上，以正庚烷为原料对所制备的催化剂进行临氢芳构化活性评价，对评价后催化剂积炭形貌、积炭组成等进行分析表征。结果表明:HZSM-5催化剂用Zn改性可以调节酸性质及孔结构性质，晶相结构组成没有变化；正庚烷转化率、液体产物中芳烃含量和BTX的选择性随ZnO负载量的增加先增加后降低，ZnO负载量为5%(质量分数)时Zn/HZSM-5催化剂临氢芳构化性能最好。Zn/HZSM-5催化剂失活主要由积炭引起，并具有较好的再生性能。

Catalytic Performance of Zn Modified HZSM-5 Catalyst in n-Alkane Hydroaromatization

A series of Zn/HZSM-5 catalysts with different ZnO loading contents were prepared by the equal volume impregnation method, and characterized by multiple methods, including BET, XRD, TPD, and Py-IR. The hydro aromatization activity of the prepared catalysts was evaluated on a small 5 mL fixed bed reactor by using n-heptane as raw material, to determine appropriate process conditions. In addition, the morphology and composition of carbon deposit of catalysts was analyzed. Results show that Zn modification can adjust the acid and pore structure properties of the HZSM-5 catalyst, and there is no impact on the crystal phase composition. The conversion of n-heptane, the aromatic content in the liquid product, and the selectivity of BTX are initially increasing and then becoming decreased with the increasing of ZnO content. When the ZnO loading mass fraction is 5%, the highest hydro-aromatization performance of Zn/HZSM-5 catalyst is obtained. The deactivation of Zn/HZSM-5 catalyst is mainly attributed to carbon deposition, and the deactivated catalyst can be well regenerated.