摘要
将聚乙烯醇（PVA）聚离子复合物（PIC）膜在95％乙醇中浸泡48h，在20—120℃（间隔20℃）下测定吸水后PIC膜的红外光谱，分析了3000cm^-1以上羟基伸缩振动基频随温度的变化情况，探讨了水与PIC膜中羟基的氢键作用。由于羟基谱带在3000cm^-1以上重叠比较严重，结合1000～1700cm^-1水与PIC膜中离子键之间的静电作用，采用二维相关分析提高光谱分辨率，定性地描述了95％乙醇中水与PIC膜之间的结合方式。结果表明：〉3000cm^-1羟基的重叠谱带得到了分辨，证明了水与膜内羟基缔合优先吸附渗透，随温度变化早于膜内羟基自缔合被解吸与乙醇分离；确认了水和PIC膜内聚电解质基的吸收，证明了水与聚电解质基团靠静电作用被吸附，随温度升高被解吸与乙醇分离。为PIC膜对95％乙醇脱水分离性能研究提供了一种新方法。
The infrared spectra（IR） of polyvinyl alcohol （PVA） polyion complex（PIC） membrane dipped in 95% ethanol for 48 h were studied in the temperature range of 20 -100℃ with an interval of 20℃ by analysing the temperature dependent variations of OH stretch vibration base bands at 〉 3000 cm^-1. Hydrogen-bond of water in 95% ethanol with PIC was studied. Since the OH bands strongly overlapped at 〉 3000 cm^-1 , combine with the static electricity effect between water in 95% ethanol and ion-bond of PIC at 1000 - 1700 -1 cm , two-dimensional infrared （2DIR） correlation analysis was applied to describe the possible combined modes between PIC and water in water-alcohol. The result showed： the OH bands overlapped was distinguish- ed at 〉 3000 cm^-1, the change of water with vary of tempertature was earlier than the intra-membrane OH self association and water was desorped to separate with ethanol. The absorption peak of water and poly-electrolyte group intra-PIC membrane was identified. The water combined with ion-bond in PIC memrane by static electricity effect was adsorbed with the temperature going up and separate with ethanol. The present study provides a novel method for investigating the separation performance of PIC membrane used in dehydration of 95% ethanol.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2007年第12期1791-1794,共4页
Chinese Journal of Analytical Chemistry
基金
国家重点基础研究发展计划"973计划"基金(No.2003CB615701)
关键词
聚乙烯醇聚离子复合物膜
95%乙醇
水分离分析
二维红外相关分析
渗透汽化
膜分离
Polyviny alcohol polyion complex membrane, ethanol-water mixture, water seperation and analysis, two-dimensional infrared correlation analysis, pervaporation, membrane separation
