多层结构钛硅（TS-1）分子筛膜的制备

发布时间：2018-01-16 20:09

本文关键词：多层结构钛硅（TS-1）分子筛膜的制备　出处：《青岛科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：TS-1分子筛具有MFI拓扑结构,因其在温和条件下优越的择形氧化性能而被人们所熟知。尽管TS-1分子筛在许多有机化合物的氧化反应中表现出良好的活性,但其微孔孔径大小只有约为0.5 nm。因此,较大分子尺寸的基质不能进入通道,它们只能与分子筛表面活性中心接触反应。因而,本文旨在改善TS-1分子筛及TS-1分子筛膜的孔道结构,进而改善其性能。具体研究内容如下:(1)通过碱处理制得具有丰富次生孔隙的多级孔TS-1分子筛。脱除模板剂后的TS-1分子筛通过TPAOH后处理可形成多级孔TS-1分子筛。催化加氢裂化法和焙烧法都能脱除TS-1分子筛中的模板剂,但前者对应的多级孔TS-1分子筛具有更高的比表面积和孔容。此外,TPAOH浓度也影响多级孔TS-1分子筛的形成。随着碱浓度的增加,溶蚀-再结晶过程加剧,空心孔隙体积增加。在分子筛/TPAOH/H2O质量比为1/3/5时,BET比表面积和孔容可达460 cm2/g和0.61 cm3/g。(2)传统的二次生长法只能制备单层的TS-1分子筛膜。基于传统的二次生长法,我们提出了周期性二次生长法用来制备双层TS-1分子筛膜,周期性二次生长法可以制得双层结构的TS-1分子筛膜。这种新型的周期性二次生长法包含两到几个周期(多个周期),每个周期包含三步,首先升温到特定温度,然后保温一段时间,最后降温到室温。通过SEM,EDS,气体渗透和脱盐测试可知,双层TS-1分子筛膜具有较好的完备性和疏水性能。由此说明通过周期性二次生长法能够合成具有更优越性能的TS-1分子筛膜。(3)通过溶解-再结晶机制在碱性悬浮液中对TS-1分子筛膜进行处理,成功制得了多级孔结构TS-1分子筛膜。通过XRD,SEM和EDS测试分析了制得的HTS-1分子筛膜的结构和组成。可以观察到HTS-1分子筛膜中存在一定量的孔洞,悬浮液中的TS-1分子筛颗粒,TPAOH模板剂和水对孔洞的形成有一定的影响。气体渗透性能和脱盐测试结果表明,具有多级孔结构的TS-1分子筛膜比传统的TS-1分子筛膜具有更好的气体/水渗透性。这对于提高膜通量的工作提供了新的见解。
[Abstract]:TS-1 molecular sieve has MFI topology. TS-1 molecular sieves are well known for their superior shape selective oxidation properties under mild conditions, although TS-1 molecular sieves exhibit good activity in the oxidation of many organic compounds. But its pore size is only about 0.5 nm. Therefore, the larger molecular size of the matrix can not enter the channel, they can only contact with the molecular sieve surface active center reaction. The purpose of this paper is to improve the pore structure of TS-1 molecular sieve and TS-1 molecular sieve membrane. Then improve its performance. The specific research contents are as follows: 1). The multiporous TS-1 molecular sieve with abundant secondary pores was prepared by alkali treatment. The TS-1 molecular sieve after removing the template was treated with TPAOH to form the multiporous TS-1 molecular sieve. The catalytic hydrogenation cracking was carried out. The template of TS-1 molecular sieve can be removed by both chemical method and roasting method. However, the former has higher specific surface area and higher pore volume. In addition, the concentration of TPAOH also affects the formation of multiporous TS-1 molecular sieve. When the mass ratio of molecular sieve / TPAOH / H _ 2O is 1 / 3 / 5, the volume of hollow pore increases. The specific surface area and pore volume of BET can reach 460 cm2/g and 0.61 cm 3 / g 路m2). The traditional secondary growth method can only produce monolayer TS-1 molecular sieve membranes, based on the traditional secondary growth method. A periodic secondary growth method was proposed to prepare bilayer TS-1 molecular sieve membranes. Double layer TS-1 molecular sieve membranes can be prepared by periodic quadratic growth method, which consists of two or several cycles (multiple cycles, each cycle consists of three steps). First to a specific temperature, then to hold it for a period of time, finally to the room temperature. Through SEMN EDS, gas permeation and desalination tests know. The bilayer TS-1 molecular sieve membrane has good completeness and hydrophobicity, which shows that the TS-1 molecular sieve membrane with better performance can be synthesized by periodic secondary growth method. TS-1 molecular sieve membranes were treated in alkaline suspensions by solution-recrystallization mechanism. TS-1 molecular sieve membrane with multilevel pore structure was successfully prepared by XRD. The structure and composition of the HTS-1 molecular sieve membrane were analyzed by SEM and EDS. A certain number of pores and TS-1 particles in the suspension of HTS-1 molecular sieve membrane were observed. TPAOH template and water have a certain effect on the formation of pores. The gas permeability and desalination test results show that. The gas / water permeability of the TS-1 molecular sieve membrane with multilevel pore structure is better than that of the traditional TS-1 molecular sieve membrane, which provides a new insight for improving the membrane flux.
【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X78

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