Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Degradation of VOC by Photocatalysts and Dark Discharge Hybrid Systems

광촉매와 암방전(dark discharge) 복합 시스템을 이용한 VOC의 분해

  • Jung, Jihoon (Department of Chemical Engineering, Kyonggi University)
  • 정지훈 (경기대학교 화학공학과)
  • Received : 2008.04.14
  • Accepted : 2008.04.19
  • Published : 2008.10.31
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Abstract

The immobilization technique is important to extend the application field of a photocatalyst. Titanium surface was changed into a $TiO_2$ thin film by the anodizing process. The anodized $TiO_2$ had photocatalytic activity, and showed sponge like shape. The photocatalytic degradation of gas phase acetaldehyde and VOCs by anodized titania has been studied in various initial concentrations, humidity and discharge potentials. The reactivity of anodized titania was increased with relative humidity, but excessive humidity led to a decrease of the reaction rate. The electric dark discharge that was combined with photocatalytic reaction enhanced the decomposition rate of the organic compounds. But excessively applied voltage caused corona discharge, which decreased the reaction rate. Optimum relative humidity was 40% and discharge potential was 5 kV under dark discharge region in photocatalytic reaction.

광촉매의 고정화는 광촉매의 이용범위를 넓히기 위해서 매우 중요한 기술이다. 광촉매를 고정화시키기 위해 티타늄 표면을 양극산화 시켜 $TiO_2$로 전환시킬 수 있다. 양극산화에 의해 제조된 $TiO_2$는 광촉매 활성을 가지고 있으며 표면은 스펀지와 비슷한 형태를 나타내었다. 다양한 초기농도, 습도, 방전전압 하에서 양극산화에 의해 티타니아를 제조 이를 이용하여 기상의 아세트알데히드와 VOC의 광촉매 분해반응을 연구하였다. 양극산화 티타니아의 반응성은 상대습도가 증가함에 따라 증가하였으나 너무 높은 습도는 반응성을 감소시켰다. 광촉매 반응과 전기 방전을 결합시키면 VOC 제거효율이 크게 증가 되었으나, 과도한 전압을 가하여 코로나 방전이 발생되면 반응속도가 오히려 감소되었다. 최적 상대습도는 40%였으며 최적 방전전압은 암방전 영역인 5 kV였다.

Keywords

Acknowledgement

Supported by : 경기대학교

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