HWAHAK KONGHAK, Vol.21, No.4, 211-219, August, 1983
역삼투 법을 이용한 유기물의 분리-셀루로오즈 아세테이트 및 PVA 막의 경우
Reverse Osmosis Separation of Organic Solutes with Cellulose Acetate and Polyvinyl Alcohol Membranes
초록
수축 온도 60 ℃에서 처리한 cellulose acetate 막(CA-I), 90 ℃에서 처리한 cellulose acetate 막(CA-II) 그리고 formalin으로 가교결합시킨 PVA막을 사용하여 100기압하의 연속식 조업 조건에서 수용액상의 여러 유기물들의 투과 거부도(rejection) 및 용액 투과량(solution flux)을 조사하였다. CA-I, CA-II와 PVA막은 1 % NaCl 용액에 대해 4 %, 12 % 및 0 %의 투과 거부도와 1,700 l, 210 l, and 290 l/㎡·day의 투과량을 보였다. 알콜류의 경우 투과 거부도는 일반적으로 낮았으며 이는 아마 물과 유사한 성질 때문으로 생각되며 메타놀, 에타놀, 이소푸로파놀의 순서로 투과 거부도는 증가하며 투과량은 줄어 들었다. 각종 당류와 아미노산은 NaCl과 유사한 성질을 보였는데 조금씩의 차이는 이들 용질과 용액, 용질과 막과의 상호작용에 의한 것으로 생각된다. 모든 용질중에서 계면 활성제인 TWeen-80은 특별한 성질을 보였는데 CA-I에서 96 %의 투과거부도와 540 l/㎡·day의 용액 투과량을 보여막 표면에 dynamic membrane을 형성하는 것으로 보인다. PVA막은 일반적으로 cellulose acetate막에 비해 거부도와 용액 투과량이 다같이 낮았다.
Permeabilities and fluxes of many organic solutions were tested under continuous reverse osmosis system at pressure of 100 atm using cellulose acetate membranes shrunk at 60 ℃(CA-I), 90 ℃(CA-II) and PVA membrane crosslinked with formalin.
CA-I, CA-II and PVC membranes were characterized by rejections of 16 %, 96 % and 14 % and water fluxes of 1,700 l, 210 l and 290 l/㎡·day respectively against 1 % NaCl testing Solution.
Alcohols showed lower rejection than other solutes due to the similarity of their chemical properties to water (CA-I, 4 %; CA-II, 12 %; PVC, 0 %). In the order of methanol, ethanol and i-chropanol, gradual rise in rejection and decrease in flux with molecular weight were observed. Various sugars and amino acids were rejected similarly to NaCl even though slight differences in rejections and fluxes were considered to be attributed to the interacion of solute molecules with membranes and solvent. Among all, surfactant Tween-80 showed peculiar behavior that even in CA-I rejections were 96 % and fluxes were 540 l/㎡day. in this case CA-I membrane behaved like CA-II perhaps due to the formation of dynamic membrane on the surface. The rejections and fluxes by PVA membrane were lower than those by cellulose acetate membranes.
CA-I, CA-II and PVC membranes were characterized by rejections of 16 %, 96 % and 14 % and water fluxes of 1,700 l, 210 l and 290 l/㎡·day respectively against 1 % NaCl testing Solution.
Alcohols showed lower rejection than other solutes due to the similarity of their chemical properties to water (CA-I, 4 %; CA-II, 12 %; PVC, 0 %). In the order of methanol, ethanol and i-chropanol, gradual rise in rejection and decrease in flux with molecular weight were observed. Various sugars and amino acids were rejected similarly to NaCl even though slight differences in rejections and fluxes were considered to be attributed to the interacion of solute molecules with membranes and solvent. Among all, surfactant Tween-80 showed peculiar behavior that even in CA-I rejections were 96 % and fluxes were 540 l/㎡day. in this case CA-I membrane behaved like CA-II perhaps due to the formation of dynamic membrane on the surface. The rejections and fluxes by PVA membrane were lower than those by cellulose acetate membranes.