论文部分内容阅读
背景:有机高分子膜中添加无机物可以改善渗透汽化膜性能,但添加物对物料渗透膜的影响及其相关机理尚需进一步的研究。目的:采用液相共混的方法制备了ZSM-5分子筛填充壳聚糖膜。考察了填充膜中分子筛对渗透汽化膜分离性能的影响。设计:对比观察实验。单位:中国科学院大连化学物理研究所。材料:实验于2006-05在中国科学院大连化学物理研究所新型膜分离技术实验室完成。壳聚糖,脱乙酰度为75%~85%,购自美国Aldrich Chemical Company;碳酸二甲酯购自美国Fluka公司,纯度99%;ZSM-5分子筛由大连化学物理研究所提供;甲醇由沈阳市联邦试剂厂提供,纯度>99.5%。方法:用液相共混的方法制备ZSM-5分子筛填充壳聚糖膜。主要观察指标:①填充膜在碳酸二甲酯/甲醇混合液中的溶胀和吸附行为。②填充膜分子筛含量及操作温度对渗透汽化膜分离性能的影响。结果:①扫描电镜表征表明分子筛在膜中分散均匀,膜表面没有明显缺陷。②膜优先吸附甲醇,其分离性能主要由溶解过程控制。③随着膜中分子筛含量的增加,膜的溶胀度增大,渗透通量大幅度提高。④渗透通量与操作温度符合Arrhenius关系式。结论:ZSM-5分子筛填充壳聚糖膜渗透汽化分离甲醇/碳酸二甲酯混合物,大大提高了壳聚糖膜的渗透通量,渗透汽化分离指数远远大于壳聚糖均质膜,具有良好的分离效果。
BACKGROUND: The addition of inorganic substances to organic polymer films can improve the performance of pervaporation membranes. However, the influence of additives on the material permeable membranes and their related mechanisms need further study. OBJECTIVE: ZSM-5 zeolite filled chitosan membrane was prepared by liquid-phase blending method. The effect of molecular sieves on the separation performance of pervaporation membranes was investigated. Design: Contrast observation experiment. Unit: Dalian Institute of Chemical Physics, Chinese Academy of Sciences. MATERIALS: Experiments were performed in a new membrane separation technology laboratory of Dalian Institute of Chemical Physics, Chinese Academy of Sciences in 2006-05. Chitosan, degree of deacetylation of 75% ~ 85%, from the United States Aldrich Chemical Company; dimethyl carbonate was purchased from Fluka Corporation, Purity 99%; ZSM-5 molecular sieve provided by the Dalian Institute of Chemical Physics; methanol from Shenyang City Federal Reagent Factory to provide, purity> 99.5%. Methods: ZSM-5 zeolite filled chitosan membrane was prepared by liquid-phase blending. MAIN OUTCOME MEASURES: ① swelling and adsorption behavior of filled membrane in dimethyl carbonate / methanol mixture. ② filler film molecular sieve content and operating temperature on the pervaporation membrane separation performance. Results: ① Scanning electron microscopy showed molecular sieve dispersed in the membrane, the membrane surface without obvious defects. ② preferential adsorption of methanol membrane, the separation performance mainly controlled by the dissolution process. ③ With the increase of molecular sieve content in the membrane, the swelling degree of the membrane increases, and the permeate flux greatly increases. ④ permeate flux and operating temperature in line with the Arrhenius relationship. CONCLUSION: Permeation and vaporization of ZSM-5 zeolite-packed chitosan membrane can significantly improve the permeation flux of chitosan membrane. The pervaporation separation index is much larger than that of chitosan homogeneous membrane and has good The separation effect.