高等学校化学学报 ›› 2020, Vol. 41 ›› Issue (12): 2710-2716.doi: 10.7503/cjcu20200465

• 无机化学 • 上一篇    下一篇

CVD法制备Sn掺杂MFI分子筛膜及其对乙醇/水体系的分离性能

彭莉, 吴政奇, 王兴, 王博轩, 顾学红()   

  1. 南京工业大学材料化学工程国家重点实验室, 南京 211816
  • 收稿日期:2020-07-17 出版日期:2020-12-10 发布日期:2020-12-09
  • 通讯作者: 顾学红 E-mail:xhgu@njtech.edu.cn
  • 基金资助:
    国家重点研发计划项目(2018YFB1501701);国家自然科学基金(批准号(22035002);21776128)和材料化学工程国家重点实验室项目(ZK201719)

Preparation of Sn-doped MFI Molecular Sieve Membrane by CVD Method and Its Separation Performance for Ethanol/water System

PENG Li, WU Zhengqi, WANG Xing, WANG Boxuan, GU Xuehong()   

  1. State Key Laboratory of Materials?Oriented Chemical Engineering,Nanjing Tech University,Nanjing 211816,China
  • Received:2020-07-17 Online:2020-12-10 Published:2020-12-09
  • Contact: GU Xuehong E-mail:xhgu@njtech.edu.cn

摘要:

采用化学气相沉积(CVD)法对MFI分子筛膜进行Sn掺杂, 制备了一种Sn-MFI分子筛膜, 并研究了其渗透汽化分离乙醇/水体系的性能. XRD, 29Si NMR, UV-Vis及分离实验结果表明, 采用CVD法在将Sn引入MFI膜时, 膜层结构基本得到保持, Sn可以进入分子筛骨架, 有效地减少了膜表面的硅羟基缺陷, 提高了膜分离乙醇/水体系时的稳定性. 在SnCl4用量为3 mL、 修饰时间为1 h时, 所得到的Sn-MFI分子筛膜的渗透汽化分离性能最佳, 并可在60 ℃下分离5%(质量分数)乙醇/水混合物时保持良好的稳定性. 在经过连续50 h渗透气化分离后, 其渗透通量仅从1.52 kg·m-2·h-1下降至1.38 kg·m-2·h-1, 分离因子从18下降至16.

关键词: MFI分子筛膜, 锡修饰, 化学气相沉积法

Abstract:

Sn-modified MFI zeolite membranes were prepared by chemical vapor deposition(CVD) method using anhydrous SnCl4 as Sn source, and were applied for the separation of alcohol-water mixture by pervaporation. SEM, XRD, 29Si NMR and UV-Vis analyses showed that Sn can be introduced into the framework of MFI zeolite membranes by CVD process with their structure remained. The surface Si—OH groups can be effectively reduced after the incorporation of Sn, and the obtained membranes showed improved stability. The zeolite membrane prepared with 3 mL of SnCl4 at autoclave bottom and the reaction time of 1 h had the best separation performance and also showed a long-term stability for the separation of 5% ethanol/water mixture at 60 ℃. After 50 h, the permeation flux slightly decreased from 1.52 kg·m-2·h-1 to 1.38 kg·m-2·h-1, and the separation factor decreased from 18 to 16.

Key words: MFI molecular sieve membrane, Sn modification, Chemical vapor deposition(CVD) method

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