ZSM-5分子筛催化1-己烯叠合反应的研究

选取一种无胺法合成的ZSM-5分子筛，对其进行不同条件下的酸处理，得到4种不同硅铝比和孔道结构的分子筛样品。采用X射线衍射、X射线荧光光谱分析、SEM扫描电镜、氮气低温物理吸附、NH3-TPD等技术对分子筛样品的结晶度、元素组成、形貌尺寸、孔结构及酸性分布等物化性质进行表征。在反应压力4.5 MPa,反应温度245 ℃及质量空速0.5 h-1条件下，考察处理后分子筛样品对正己烯叠合反应性能的影响。结果表明:正己烯的转化率随硅铝比的增加逐渐降低；目的产物己烯二聚物收率随硅铝比增加呈现先增加后减小的趋势，在硅铝比为102时，己烯二聚物收率达到最大值；低硅铝比分子筛样品中副产物多、积炭量较大。综合考虑目的产物收率及原料的利用率，硅铝比为102的ZSM-5分子筛最适合用于生产喷气燃料组分。

OLIGOMERIZATION OF 1-HEXENE OVER ZSM-5 ZEOLITE

ZSM-5 zeolite synthesized from amine-free system was dealuminated by acid treatment under different conditions. Four ZSM-5 zeolites with different aluminum content and pore structure were prepared. The samples were characterized by XRD, XRF, BET, and NH3-TPD techniques to analyze the crystallinity, element composition, morphology and size, pore structure as well as acidity distribution. The performance of 1-hexene oligomerization was evaluated over ZSM-5 zeolites at the conditions of 4.5 Pa，245 ℃ and mass hourly space velocity of 0.5 h-1. The results show that with increasing the Si/Al ratio，the conversion of 1-hexene decreases while the yield of dimers shows a tendency of firstly increase and then decrease. The maximum yield is obtained at the Si/Al ratio of 102. The ZSM-5 zeolite with lower Si /Al ratio has more by-products and more carbon deposition. From yield of dimers and raw material utility consideration, the ZSM-5 zeolite with Si/Al of 102 is the most suitable catalyst for the production of jet fuel component.