V2O5/TiO2계 촉매상에서 NH3에 의한 NOx의 선택적환원은 310의 지구온난화지수를 갖는 N2O의 또 다른 인위적인 배출원이 될 수 있는 것으로 보고되고 있으므로, 본 총설은 화석연료를 연소시키는 화력발전소용 상기 촉매상에서 SCR 탈질반응 동안에 N2O 생성과 관계되는 주요 변수들의 유의성을 다루고자 한다. NH3-SCR 탈질반응에서 N2O 배출은 NH3 산화반응에 더하여 반응 중에 존재하는 NOx와 NH3 간의 부반응을 통해 일어나고. 이 부반응들의 정도는 SCR 촉매의 활성성분인 V2O5의 함량과 조촉매의 종류(WO3와 MoO3), 반응온도, NO2/NOx 비율, 산소농도, 공간속도, 수분함량, 열처리 등과 같은 유입가스 조건과 운전변수 및 화력발전소 현장에 설치된 상용 SCR 탈질공정에서 격은 촉매의 이력에 크게 의존한다. 상기의 모든 변수들이 탈질반응에서 N2O 생성과 관계된다고 할지라도, 몇몇 핵심변수들이 N2O 생성에 미치는 영향과 상용 SCR 공정에서 N2O 생성을 억제할 수 있는 방안이 고찰되었다.

Selective catalytic reduction of NOx by NH3 (NH3-SCR) over V2O5/TiO2-based catalysts is recently reported to be an anthropogenic emitter of N2O that is a global warming gas with a global warming potential of 310. Therefore, this review will get a touch on significance of some parameters regarding N2O formation in the deNOxing reaction for fossil fuels-fired power plants applications. The N2O production in NH3-SCR reaction with such catalysts occurs via side reactions between NOx and NH3 in addition to NH3 oxidation, and the extent of these undesired reactions depends strongly on the loadings of V2O5 as a primary active component and the promoter as a secondary one (WO3 and MoO3) in the SCR catalysts, the feed and operating variables such as reaction temperature, NO2/NOx ratio, oxygen concentration, gas hourly space velocity, water content and thermal excursion, and the physical and chemical histories of the catalysts on site. Although all these parameters are associated with the N2O formation in deNOxing reaction, details of some of them have been discussed and a better way of suppressing the N2O production in commercial SCR plants has been proposed.

Nitrous Oxide (N2O) Nitrogen Oxides (NOx) Selective Catalytic Reduction Titania-supported Vanadia-based Catalysts Side Reactions

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