A Study on Chlorine Resistance Improvement of Reverse Osmosis Membrane by Surface Modification

역삼투 분리막의 표면개질을 이용한 내염소성 향상에 관한 연구

  • Kim, Younggil (College of Environment and Applied Chemistry, Kyung Hee University) ;
  • Kim, Nowon (Department of Environmental Engineering, Dongeui University) ;
  • Lee, Yong-Taek (College of Environment and Applied Chemistry, Kyung Hee University)
  • 김영길 (경희대학교 환경응용화학대학) ;
  • 김노원 (동의대학교 환경공학과) ;
  • 이용택 (경희대학교 환경응용화학대학)
  • Published : 2005.12.01

Abstract

Polyamide membrane degradation by chlorine has been studied to improve membrane durability. In this study, it was found that the salt rejection was reduced rapidly and flux of the membrane was increased slowly far membrane treated under chlorine condition. In order to improve resistance to chlorine of the polyamide reverse osmosis membrane, fluorine-containing silane coupling agent (FSCA) was introduced to surface modification. Surface properties and chlorine resistance of silane modified membrane were compared with virgin membrane. It was found that the surface of silane modified membrane has dense structure according to FSCA concentration increasing. The results of surface analysis suggest that FSCA retrieved a severe change in the hydrophobicity and surface roughness. In addition, it appears that FSCA can enhance chlorine resistance due to the interaction of such substance with free radical chlorine.

본 연구에서는 polyamide계 방향족 역삼투막이 염소 라디칼에 의해 polyamide 결합이 분해되어 염배제율이 급격히 감소되는 반면 수투과도는 증가되는 것을 확인하였다 이러한 polyamide 역삼투막의 염소에 대한 저항성을 향상시키기 위해서 불소기 함유 실란커플링제(fluorine-containing silane coupling agent, FSCA)를 이용하여 역삼투막 표면 개질 후 막에 대한 표면 특성 및 내염소성 변화를 관찰하였다. 그 결과 FSCA의 농도가 증가될수록 막 표면이 dense하게 도포되었으며, 원소분석을 통해 FSCA가 부착되어 있음을 확인하였다. 또한 개질한 막 표면 조도는 감소되고 표면의 소수성이 증가됨을 접촉각의 증가로 확인 할 수 있었다. 이 결과를 종합하여 볼 때, 역삼투막을 FSCA로 표면개질 함으로써 개질막의 염소에 대한 저항성을 향상시킬 수 있었다.

Keywords

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