关键词: 渗透汽化, 海藻酸钠, 磷钨酸, 甲醇水溶液, 活化能

Abstract: Highly water selective pervaporation hybrid membranes were prepared by incorporating phosphotungstic acid (PTA) into sodium alginate (SA). The resulting membranes were characterized by thermogravimetric analysis (TGA). The membranes were tested for pervaporation dehydration of methanol at a higher methanol concentration of 80%─95% in the temperature range of 30～60℃. Experimental results demonstrated that with the addition of PTA the separation performance of hybrid membranes was notably improved. With 6% addition of PTA, the membrane separated 5% water solution at 30 ℃, total flux was 318.2g/(m2?h) and separation factor was 656.9, improved by more than 3.7 times and 26.3 times respectively. From the temperature dependency and permeation values, the Arrhenius activation parameters were estimated. The activation energy of all membranes decreased with increasing amount of PTA. It suggested that permeation was more easy through the hybrid membranes with the addition of PTA.

Key words: pervaporation, sodium alginate, phosphotungstic acid, water-methanol mixtures, activation energy