摘要
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、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4.5MPa、反应温度245℃及质量空速0.5h-1的条件下,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反应时副产物多、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。
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 NHa-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.
出处
《石油炼制与化工》
CAS
CSCD
北大核心
2015年第9期7-11,共5页
Petroleum Processing and Petrochemicals