Infrared Spectral Studies of Separation of QAPVA/PMPVA Complex Membrane for Dehydrating Water of 95% Ethanol
MENG Ping-rui1, KANG Zhi-hui1, LI Liang-bo1, RONG Feng-ling1, LI Ruo-xin2
1. School of Chemistry and Chemical Engineering, University of Jinan, Ji’nan 250022, China 2. State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
Abstract:Quaternized polyvinyl alcohol (QAPVA) and phosphate monoester polyvinyl alcohol (PMPVA) were self-assembled into polyion complex (PIC) membrane. The infrared spectra (IR) of PIC membrane dipped in 95% ethanol for 48 h were studied in the temperature range of 20-120 ℃ with an interval of 20 ℃ by analyzing the temperature dependent variations of OH stretch vibration base bands (νOH) at >3 000 cm-1. Hydrogen-bond of water in 95% ethanol with PIC was studied. Since the νOH strongly overlapped at >3 000 cm-1, combined with the static electric effect between water in 95% ethanol and ion-bond of PIC at 1 300-1 700 cm-1, two-dimensional infrared (2DIR) correlation analysis was applied to describe the possible combined modes between PIC and water in water-alcohol. The result shows that the νOH overlapped was distinguished at >3 000 cm-1, the change of water with varing tempertature was earlier than the intra-membrane OH self association and water was desorbed to separate from ethanol. The absorption peak of water and poly-electrolyte group intra-PIC membrane was identified. The water combined with ion-bond in PIC membrane by static electric effect was adsorbed with the temperature going up and separate from ethanol. The present study provides a simple method for investigating the separation performance of PIC membrane used in dehydration of organic compounds.
Key words:95% ethanol-water mixture;PVA polyion complex membrane;IR;Two-dimensional IR correlation analysis;Pervaporation
孟平蕊1,康智慧1,李良波1,荣凤玲1,李若昕2. QAPVA/PMPVA复合物膜对95%乙醇脱水的IR研究[J]. 光谱学与光谱分析, 2008, 28(12): 2812-2815.
MENG Ping-rui1, KANG Zhi-hui1, LI Liang-bo1, RONG Feng-ling1, LI Ruo-xin2. Infrared Spectral Studies of Separation of QAPVA/PMPVA Complex Membrane for Dehydrating Water of 95% Ethanol. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2008, 28(12): 2812-2815.