Journal of Korean Society of Environmental Engineers (대한환경공학회지)

Korean Society of Environmental Engineers (대한환경공학회)
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Formation Mechanism of Chlorate ($ClO_3\;^-$) by Electrochemical Process

전기화학적 공정에 의한 클로레이트의 생성메커니즘

  • Baek, Ko-Woon (Department of Environmental Engineering, Yonsei University, YIEST) ;
  • Jung, Yeon-Jung (Department of Environmental Engineering, Yonsei University, YIEST) ;
  • Kang, Joon-Wun (Department of Environmental Engineering, Yonsei University, YIEST) ;
  • Oh, Byung-Soo (Gwangju Institute of Science and Technology, Center for Seawater Desalination Plant)
  • 백고운 (연세대학교 환경공학과, 환경과학기술연구소) ;
  • 정연정 (연세대학교 환경공학과, 환경과학기술연구소) ;
  • 강준원 (연세대학교 환경공학과, 환경과학기술연구소) ;
  • 오병수 (광주과학기술원, 해수담수화 플랜트 사업단)
  • Received : 2009.01.13
  • Accepted : 2009.07.22
  • Published : 2009.08.31
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Abstract

This study was done to find out the formation mechanism of chlorate by electrochemical process using chloride ion ($Cl^-$) as an electrolyte. Firstly, the effective factors such as pH and initial chloride concentration were figured out to see the formation property of chlorate during electrolysis. And the relation of free chlorine, and mixed oxidants such as OH radical and ozone with chlorate were estimated to concretize the formation mechanism. As a result, it was found that the major reaction of chlorate formation would be electrochemical reaction with free chlorine, and also the direct oxidation of chloride ion and the reaction by OH radical were participated in the formation of chlorate. Moreover, it was observed that formed chlorate was oxidized to perchlorate. Lastly, the optimum condition was recommended by comparing free chlorine with chlorate concentration during the electrochemical process with the different electrode separation.

본 연구는 염화 이온 ($Cl^-$)을 전해질로 이용하는 전기화학적 공정에서 생성되는 염소산화부산물인 클로레이트 ($ClO_3\;^-$, 염소산염)의 생성 메커니즘을 알아보기 위해 수행되었다. 우선, pH 및 초기농도에 따른 생성 특성을 살펴보았으며, 유리염소 생성과의 관련성 및 오존, OH 라디칼 등의 혼합산화제의 영향을 간접 평가하여 클로레이트의 생성 메커니즘을 구체화하였다. 그 결과, 클로레이트의 생성은 유리염소 (HOCl/$OCl^-$)의 전기화학적 반응을 주된 반응으로 하며, 염화 이온의 직접 양극산화 반응 및 OH 라디칼에 의한 경로가 있음을 확인하였다. 이어서 생성된 클로레이트가 퍼클로레이트로 산화되는 반응도 볼 수 있었다. 또한, 전극 간격에 따른 생성 농도를 유리염소 생성과 함께 평가하여, 유리염소 생성 효율은 극대화 시키되 클로레이트의 발생을 최소화 할 수 있는 최적조건을 찾는 방안을 제시하였다.

Keywords

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