Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Photochemical Conversion of NOX in Atmosphere by Photocatalyst Coated Mortar

광촉매 코팅한 모르타르를 이용한 대기 중 NOX의 광화학적 변환

  • Hyeon Jin (Department of Chemical Engineering, Kangwon National University) ;
  • Kyong Ku Yun (Department of Civil Engineering, Kangwon National University) ;
  • Hajin Choi (School of Architecture, Soongsil University) ;
  • Kyo-Seon Kim (Department of Chemical Engineering, Kangwon National University)
  • 진현 (강원대학교 화학공학과) ;
  • 윤경구 (강원대학교 토목공학과) ;
  • 최하진 (숭실대학교 건축학부) ;
  • 김교선 (강원대학교 화학공학과)
  • Received : 2022.10.14
  • Accepted : 2022.12.08
  • Published : 2023.05.01
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Abstract

This study was performed to convert NOx in atmosphere by photochemical reaction utilizing the eco-friendly solar energy. The mortar specimen coated with photocatalyst was fabricated and the photochemical conversion efficiency of NOx was analyzed. The photocatalyst coated concrete was fabricated by first adding TiO2 photocatalyst on the bottom of mold first and next adding cement mortar and, then, curing the concrete mortar. The grease was sprayed on the bottom of mold in advance so that the concrete can be demolded easily after curing. The conversion efficiencies of NOx by photochemical reactions were investigated systematically by changing the process variable conditions of amount of TiO2 coating, UV-A light intensity, total gas flow rate, relative humidity and initial NOx concentration. It was confirmed that the photocatalyst coated concrete fabricated in this study could convert NOx successfully for various process conditions in atmosphere. In future, we believe this research result can be utilized as basic data to design the infrastructure of building, tunnel and road for controlling efficiently the air pollutants such as NOx, SOx, and VOCs.

친환경적인 태양에너지를 사용하여 대기오염물질인 NOx를 광화학적 반응으로 변환시키는 연구를 수행하였으며 광촉매를 모르타르 표면에 코팅한 시편을 제조하여 NOx의 광화학적 전환율을 분석하였다. TiO2 광촉매를 거푸집의 하부에 먼저 넣고 시멘트 모르타르를 넣은 후 시멘트 모르타르를 양생시켜 광촉매 코팅된 콘크리트를 제조하였다. 거푸집 바닥에 미리 grease를 도포함으로써 양생 후에 콘크리트가 쉽게 탈형될 수 있도록 하였다. TiO2 코팅 양, UV-A 광 세기, 전체 기체 유량, 상대 습도, 그리고 초기 NOx 농도와 같은 공정 변수를 체계적으로 변화시켜서 광촉매 반응에 의한 NOx의 전환율을 조사하였다. 제조된 광촉매 코팅된 콘크리트가 다양한 공기 중의 공정 변수 조건에서 NOx를 성공적으로 전환시키는 것을 확인하였다. 본 연구 결과는 향후 NOx, SOx, VOCs 등의 대기오염물질을 효과적으로 제어하기 위한 건물, 터널, 또는 도로와 같은 인프라 시설의 설계를 위한 기초 자료로 활용될 수 있을 것으로 본다.

Keywords

Acknowledgement

본 연구는 2022년도 정부(산업통상자원부)의 재원으로 한국에너지기술평가원의 지원을 받아 수행된 연구입니다(20229A10100120). NOX 농도 분석을 위한 NO-NO2-NOX 분석기 사용을 허락해 주신 이대원 교수님께 감사 드립니다.

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