The Preparation Of Collagen Pervaporation Membranes And It’s Application In The Separation Of Ethanol/water

Pervaporation is a membrane separation technology, which were sepreated mainly by using different diffusion rates of different components dissolved in the membrane to reach separation. Pervaporation had the advantage of high single-stage separation performance,low energy consumption,simple process, non-polluting and no other agents added during the process. Pervaporation is commonly used for the separating of close-boiling and azeotropic liquid mixtures, which are difficult to be separated by distilling, distillation and other technique.Collagen as a natural polymer material with good film-forming ability, also has certain heat stability. Modifying the acid soluble collagen was extracted from the bark of grass carp then be modified by glutaraldehyde, used as preparation pervaporation membrane material, which was not only an innovation to membrane industry, but also very meaningful for the application of collagen.Pervaporation membrane was made by collagen modified by glutaraldehyde, and applied to separate in ethanol/water. The experiment reviewed pervaporation separation performance of collagen membranes was affected by the temperature and concentration of ethanol/water solution. The results showed that collagen pervaporation membrane had better performance seperating in ethanol, the collagen had good stain resistance, heat resistance. When the quality ration of collagen with mass fraction 2% and glutaraldehydein with mass fraction 3% was 5:1, the crosslinking temperature was 45 ℃, operating temperature was 50 ℃, the separation factor and flux were relatively good. When separating the ethanol/water with mass fraction 20%, the separation factor could be 2.96,the flux was 92.7 g/(m2·min). Separating the ethanol/water with mass fraction 82%, the separation factor could be 1.87, the flux of was 46.7 g/(m2·min).Collagen(mass ratio(5:1)) after modified by Glutaraldehyde with polyvinyl alcohol(PVA) of 4% were blended, Experimented the prepared pervaporation membrane with different concentrations of ethanol/water, reviewed that if the sperating performance of membranes was affected by concentration of Casting Solution, operating temperature and concentration of ethanol/water. The results showed that blended membranes had better stain resistance, heat resistance. When the mass ration of modified collagen and PVA were5:2, the modification temperature was 45 ℃, operating temperature was 50 ℃, When separating the ethanol / water solution with mass fraction 90%,the separation factor could be reached 6.69, the flux of was 52.53 g/(m2·min). Separating the ethanol/water solutionwith mass fraction 5%, the separation factor was 4.36, the flux of was 82.11 g/(m2·min).