CU-SSZ-13分子筛的合成及应用

发布时间：2018-05-13 12:26

  本文选题：Cu-SSZ-13 + 分子筛　； 参考：《天津工业大学》2017年硕士论文

【摘要】：随着石油资源的日益短缺以及乙烯、丙烯需求量的增长,开发出一条替代石油生产乙烯、丙烯的路线受到广泛关注,甲醇制烯烃(MTO)技术就是一条从非石油资源制取烯烃的新路线。甲醇制烯烃工艺的核心是催化剂,主要有SAPO-34分子筛、SSZ-13分子筛等。尽管SSZ-13分子筛在MTO反应中具有优异的催化性能,但是用于合成该分子筛的模板剂N,N,N-三甲基金刚烷铵(TMAdaO-H)价格昂贵且依赖进口。Cu-SSZ-13分子筛在催化氧化还原反应中具有非常好的催化性能和水热稳定性,但目前对Cu-SSZ-13分子筛的研究主要集中在氮氧化物的脱除领域,有关其催化MTO性能的研究,文献报道褥得少。本论文以低廉的铜氨络合物(Cu-TEPA)为模板剂,通过原位水热合成法制备了 Cu-SSZ-13分子筛。系统研究了 Cu-SSZ-13分予筛的合成影响因素,包括氢氧化钠和水的用量、硅铝比以及晶化时间等,得出了合成Cu-SSZ-13分子筛的最优反应原料和反应条件:14℃下晶化4d。当4.7≤n(Na20):n(Al203)≤5,10≤Si/Al≤11.5,185≤n(H2O):n(Al2O3)≤230时,合成的Cu-SSZ-i3分子筛结晶度最高且MTO催化性能最好。考察了硝酸铜和硫酸铜对Cu-SSZ-13分子筛的晶相结构和形貌的影响,测试了两种铜盐制备的Cu-SSZ-13分子筛和金属改性的Cu-SSZ-13分子筛在甲醇制烯烃(MTO)中的催化性能。用X射线荧光光谱(XRF)、X射线衍射(XRD)、扫描电子显微镜(SEM)、N2等温吸附-脱附(BET)和NH3程序升温脱附(NH3-TPD)对催化剂进行了表征。结果表明:在MTO反应中,硝酸铜制备的Cu-SSZ-13分子筛的氢转移反应剧烈,反应初期丙烷选择性达到40%,远高于硫酸铜制备的Cu-SSZ-13分子筛的19%。锰改性的Cu-SSZ-13分子筛明显提高了抗积炭失活能力,在反应温度440℃和质量空速5h-1条件下的催化寿命从未改性的30min延长到 65min。比较了不同浓度的稀硝酸改性的Cu-SSZ-13分子筛与氯化铵处理过的Cu-SSZ-13分子筛的MTO催化性能。结果表明,稀硝酸改性的Cu-SSZ-13分子筛双烯选择性略高于氯化铵处理过的Cu-SSZ-13分子筛。
[Abstract]:With the increasing shortage of petroleum resources and the increasing demand for ethylene and propylene, the route of developing a substitute for petroleum to produce ethylene has received extensive attention. Methanol to olefin (MTO) technology is a new route to produce olefin from non-petroleum resources. The core of methanol to olefin process is catalyst, mainly SAPO-34 molecular sieve SSZ-13 molecular sieve and so on. Although SSZ-13 molecular sieve has excellent catalytic performance in MTO reaction, However, the template for the synthesis of this molecular sieve, NZN- N- trimethyl amantadine (TMAdaO-H), is expensive and dependent on imported. Cu-SSZ-13 molecular sieve has very good catalytic performance and hydrothermal stability in the catalytic redox reaction. However, the research on Cu-SSZ-13 molecular sieve is mainly focused on the removal of nitrogen oxides, and the research on its catalytic MTO performance is seldom reported in the literature. In this paper, Cu-SSZ-13 molecular sieve was prepared by in situ hydrothermal synthesis with cupric ammonia complex (Cu-TEPA) as template. The factors affecting the synthesis of Cu-SSZ-13 sieve were systematically studied, including the amount of sodium hydroxide and water, the ratio of Si to Al and crystallization time, etc. The optimum reaction materials and reaction conditions for the synthesis of Cu-SSZ-13 molecular sieve were obtained. When 4.7 鈮，

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