分子筛膜的性能和制备研究进展

本文介绍了近年来分子筛膜研究的新进展,内容包括分子筛膜的分离机理、分子筛膜的种类,制备方法和它的应用研究,同时对分子筛膜的缺陷和清除方法,分子筛膜研究中目前存在的问题进行了评述与讨论。     

分子筛膜的制备和研究进展

本文综述了分子筛膜的各种制备方法,如原位水热合成法、晶种法、微波加热法、化学气相沉积法、脉冲激光蒸镀法等,介绍了分子筛膜在物质分离和膜催化反应等方面的应用,同时讨论了在分子筛膜制备过程中膜缺陷的形成及其消除方法,最后提出了分子筛膜的研究展望。     

分子筛膜的研究及进展

本文从载体选择、膜的制主表征、分子筛膜在气液分离、反应过程等方面总结了领域研究现状及进展情况。重点介绍了全硅沸石、ＺＳＭ＝５沸石膜的备、表征方法、并提出了一些关于开展分子筛膜制备及工业性应用研究方面的看法。     

无机膜制备技术的进展

以无机膜的制备技术为重点,综述了近１０年来无机膜的制备技术工艺、基础理论和应用研究取得的进展 。     

分子筛膜的合成与应用研究进展

介绍了分子筛膜的合成方法,如水热合成法、二次生长法、连续流合成法、微波辅助合成法、杂原子掺杂法、混合基质法等,阐述了分子筛膜在分离和催化中的应用,并对分子筛膜的发展方向进行了展望,认为加强分子筛膜的成膜机理和改性研究,并深入开发分子筛膜在催化及分离中的应用,制备出具有工业应用价值的分子筛膜.     

热缩聚煤沥青压型制备分子筛炭膜：炭膜基板的制备（Ⅰ）

以一种热缩聚煤沥青为原料制务炭膜基板，考察了预氧化、炭化条件对炭膜基板的气体透过性和选择性的影响。结果表明：炭膜基板对ＣＯ_２／Ｈ_２及Ｎ_２／Ｈ_２有一定的分离能力，分离系数在３．０左右，气体的透过速率在１０~（－３）ｃｍ~３（ＳＴＰ）／（ｃｍ~２·ｓ·ｃｍＨｇ）数量级，同时，还考察了炭化温度对炭膜基板的机械强度、失重和收缩程度的影响。     

Silicalite-1分子筛膜用于渗透汽化分离

渗透汽化分离是新型的膜分离技术，它具有低能耗、低设备投资及容易工业放大等优点。以往在渗透汽化分离中多使用有机膜，但在分离中有机膜难免有溶涨的缺点。无机膜在此方面有着有机膜无可比拟的优势。另外，在渗透汽化分离中很少对提取有机物进行研究。利用Silicalitc-1分子筛膜可以从有机物／水混合物中提取有机物。     

炭膜的制备研究

本文在大量文献及作者工作的基础上,对炭膜的分离机理、应用、制备方法以及制备工艺参数与膜性能的关系进行了综述.     

NaA型分子筛膜合成及应用进展

介绍了NaA型分子筛膜在合成及应用方面的研究进展,重点介绍了NaA型分子筛膜在渗透汽化分离方面的实际应用,展望了NaA型分子筛膜的应用前景。     

分子筛复合膜

本文综述了分子筛复合膜的制备方法，介绍了分子筛复合膜在混保气体分离中的应用及分离机理。     

沸石膜渗透蒸发性能研究进展

渗透蒸发由于其对近沸物和恒沸混合物高效的分离性能而成为当今一个基本的分离操作单元。本文首先对渗透蒸发装置及分离性能表征简要总结,然后重点概述了对沸石膜的渗透蒸发应用和渗透蒸发过程影响因素,最后针对当前研究现状,展望了沸石膜在渗透蒸发方面的发展前景。     

在粗孔a-Al_2O_3载体上合成NaA沸石膜

采用稀释的水玻璃作为分散介质配成0.5%(w)的NaA沸石悬浮液,对粗孔a-Al2O3(孔径3~5 mm)载体管修饰并预涂晶种,进一步采取原位水热晶化法在a-Al2O3载体管外表面制备NaA沸石膜. 重复合成5次后,在载体表面形成一层致密、连续的沸石晶体层. 由XRD确定该晶体为A型沸石,由SEM可观察到膜厚约15~20 mm,膜表面上的沸石晶体大小约为3~5 mm,晶体之间紧密孪生在一起,看不出晶间空隙. 制备的NaA沸石膜的H2渗透率为3.0510-6 mol/(m2sPa), 对H2/N2和H2/C3H8的理想分离因数分别为6.9和15.6,超过对应的努森扩散值3.74和4.69,说明所制备的NaA沸石膜具有分子筛分性能.     

Functional Polymeric Membrane Containing Inorganic Nanoparticle: Recent Advances and Applications

Considerable industrial and academic interest is garnered by polymer/inorganic nanoparticle composites in technical applications. In this respect, inorganic nanoparticles such as silica, titania, and zinc oxide are dispersed in polymer matrices. Tribological behavior and high-impact resistance of nanoparticles have opened new opportunities for polymeric membranes. Current article overviews research in the field of inorganic nanoparticle-reinforced polyetherimide, polyvinyl alcohol, poly(etheretherketone), polylactic acid, and polyvinyl chloride. The membranes were fabricated through distillation precipitation, solution casting, and microwave-assisted protocol. Property–structure relationship of polymer/inorganic nanoparticle membranes and potential applications in medical, fuel cell, and gas separation have been discussed.     

Preparation of Palladium-Silica Conjugated Membrane for Selective Hydrogen Permeation

Palladium membranes were prepared on an a-alumina support by metal-organic compound chemical vapor deposition (MOCVD) method from palladium(Ⅱ) acetate precursor. Permeation properties of hydrogen and helium gas were studied as a function of the number of times of deposition of palladium on the peeling off phenomenon of palladium, which is common in electroless plated membrane, was observed. Silica was introduced into the pores to prevent the palladium grain from peeling off. The palladium-silica conjugated membrane does not show the peeling off phenomenon and can withstand the high temperature up to 800CCCC which is the upper limit of our apparatus. The separation factor for hydrogen gas over carbon dioxide gas was improved with the increase of number of times of silica coating by sacrificing the H2 permeation and finally increased to four times. The improvement on the separation of hydrogen gas over carbon dioxide for palladium-silica conjugated membrane was evaluated and a model of permeation pattern     

Pd-SiO2复合膜的氢气选择渗透特性

Palladium membranes were prepared on an a-alumina support by metal-organic compound chemical vapor deposition (MOCVD) method from palladium(Ⅲ) acetate precursor. Permeation properties of hydrogen and helium gas were studied as a function of the number of times of deposition of palladium on the peeling off phenomenon of palladium, which is common in electroless plated membrane, was observed. Silica was introduced into the pores to prevent the palladium grain from peeling off. The palladium-silica conjugated membrane does not show the peeling off phenomenon and can withstand the high temperature up to 800℃ which is the upper limit of our apparatus.The separation factor for hydrogen gas over carbon dioxide gas was improved with the increase of number of times of silica coating by sacrificing the H2 permeation and finally increased to four times. The improvement on the separation of hydrogen gas over carbon dioxide for pulladium-silica conjugated membrane was evaluated and a model of permeation pattern (palladium and silica) was proposed. This model suggests that the separation factor for hydrogen over carbon dioxide could be improved by introducing silica layer because the silica layer fills the pores and reduces the gas permeation without sacrificing the hydrogen permeation through the palladium region. These results indicate that the introduction of silica into the palladium grain is a promising means to improve the hydrogen separation performance of palladium based composite membranes.     

沸石晶种层形成的影响因素及其对Silicalite-1型沸石膜生长的影响

研究了晶种二次成膜法中提拉法晶种涂层形成的主要影响因素,如载体性质、晶种大小和涂层溶剂及晶种层质量对Silicalite-1沸石水热生长成膜的影响.SEM和XRD分析表明,载体的性质、晶种大小及涂层溶剂对晶种层的形成均有很大影响.晶种在平整的小孔径陶瓷载体上易沉积形成连续晶种层,不平整的大孔载体上难以形成连续晶种层.弱极性的乙醇晶种悬浮液有利于晶种粒子的沉积;疏水性的炭载体不宜采用强极性的水作为溶剂进行晶种涂层,而宜在乙醇悬浮液中进行晶种涂层;纳米级小晶粒晶种易形成连续、均匀的晶种层,大晶粒(600 nm和2.2μm)晶种不易在大孔载体上沉积.用小晶粒晶种形成的连续晶种层,沸石生长形成的膜质量好.结果表明,沸石膜的质量取决于晶种层的质量.     

沸石分子筛膜的应用与研究进展

介绍了NaA沸石分子筛膜的合成方法以及NaA沸石分子筛膜在液体分离、气体分离、催化反应,光学及光催化反应等高新技术领域的应用,提出了沸石分子筛膜面临的问题与挑战。     

沸石膜的合成最新进展

介绍了合成沸石膜的常用方法,如：原位水热合成法、二次生长法、微波法及脉冲激光烧蚀法,并对各种方法进行了比较,指出了其优缺点。提出了沸石膜合成的目标：合成由小晶粒组成的薄而连续的定向膜。对载体的选择及处理方法进行了总绔,并对沸石膜的合成方法进行了展望。