Microwave-assisted Photocatalytic Degradation of Methylene Blue

마이크로웨이브가 부가된 광촉매에 의한 메틸렌블루의 분해

  • Kim, Yu-Bong (Department of Environmental Engineering, Sunchon National University) ;
  • Jo, A-Ra (Department of Environmental Engineering, Sunchon National University) ;
  • Ra, Deog-Gwan (Department of Environmental Engineering, Sunchon National University) ;
  • Park, Jae-Hyeon (Clean Energy System Research Center, Korea Institute of Energy Research) ;
  • Kim, Sun-Jae (Department of Nano Science and Technology, Sejong University) ;
  • Jung, Sang-Chul (Department of Environmental Engineering, Sunchon National University)
  • 김유봉 (순천대학교 환경공학과) ;
  • 조아라 (순천대학교 환경공학과) ;
  • 라덕관 (순천대학교 환경공학과) ;
  • 박재현 (에너지기술연구원 청정시스템연구센터) ;
  • 김선재 (세종대학교 나노공학과) ;
  • 정상철 (순천대학교 환경공학과)
  • Published : 2008.08.31

Abstract

In this study, the photocatalytic degradation of methylene blue in TiO$_2$ particles-dispersed water solution was carried out by irradiating microwave and UV light simultaneously. A microwave-discharged electrodeless UV lamp was developed to use microwave and UV simultaneously for photocatalytic reactions. The results of photocatalytic degradation of methylene blue showed that the decomposition rate increased with the microwave intensity, the circulating fluid velocity, and the amount of TiO$_2$ particles and auxiliary oxidizing agents added. Especially, the rate constant of H$_2$O$_2$-added photocatalytic reaction increased about three times from 0.0075 min$^{-1}$ to 0.0250 min$^{-1}$ when microwave was additionally irradiated. This study demonstrates that the microwave irradiation can play a very important role in photocatalytic degradation using peroxides although it is not easy to quantitatively assess the effect of microwave on photocatalytic reactions from the experimental data of this study.

Microwave와 자외선을 동시에 조사하여 광촉매분말이 분산된 메틸렌블루수용액의 분해실험을 하였다. 광촉매반응에 microwave와 자외선을 같이 사용하기 위하여 microwave에 의해 방전되는 무전극자외선램프를 제작하였다. 실험결과 microwave의 강도, 반응수용액의 순환유속, TiO$_2$ 분말의 첨가량 그리고 산화보조제의 첨가량이 증가할수록 광촉매분해속도가 증가하였다. 특히 과산화수소를 첨가한 광촉매반응에 microwave를 부가한 실험의 반응속도상수는 0.0250 min$^{-1}$이고 광촉매반응에 과산화수소만을 첨가한 경우의 속도상수는 0.0075 min$^{-1}$로 약 3배 정도 높은 값을 나타내었다. 본 연구의 결과로부터 광촉매반응에 microwave가 미치는 영향을 정량적으로 평가하기는 어렵지만, 과산화수소가 첨가되는 광촉매반응에 microwave의 조사가 매우 중요한 인자인 것을 알 수 있었다.

Keywords

References

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