The Study of NOx Removal Efficiency by NH3 over V2O5/TiO2

The Study of NOx Removal Efficiency by NH3 over V2O5/TiO2

The selective catalytic reduction (SCR) reaction of promoter catalysts was investigated in this study. TiO2 of pure anatase type was used as support. Activation measurement of prepare catalysts practiced on a fixed reactor packing by the glass bead after fill up catalysts in 1/4 inch stainless tube. The reaction temperature was measured by K-type thermocouple and catalyst was heated by electric furnace. The standard compositions of the simulated flue gas mixture in this study were as follows : NO 1780ppm, NH3 1780ppm, O2 1%, and N2 as balance gas. In this study, gas analyzer was used to measure the outgassing gas. Catalyst bed was handled for 1hr at 450℃, and the reactivity of the various catalyst was determined in a wide temperature range. Conversion of NH3/NO ratio was practiced at 1, 1.5, 2 respectively and conversion of O2 concentration was practiced at respectively and the space velocity were as follows : 10,000, 15,000, 17,000 hr-1 respectively. It was found that the maximum conversion temperature range was in a 50℃, and it was also very sensitive at space velocity, O2 concentration, and NH3/NO ratio. It was found that the maximum conversion temperature of (W, Mo, Sn)-V2O5/TiO2 catalysts was broaden. Specially WO3-V2O5/TiO2 catalyst appeared nearly 100% conversion at not only above 300℃ but also below temperature of 25 0℃. At over 300℃, NH3 oxidation was decreased as decreasing of surface excess oxygen. Also WO3-V2O5/TiO2 catalyst does hardly appear to effect on space velocity, O2 concentration and NH3/NO ratio.