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A series of different transition metals(V,Co,Cr,Mn,Fe,Ni,Cu and Zn) promoted H-ZSM-5 catalysts were prepared by impregnation method and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The catalytic activity of these catalysts was evaluated for the selective catalytic reduction(SCR) of NO with NH_3 as reductant in the presence of oxygen.The results revealed that the catalytic activity of Cu-ZSM-5 nanocatalyst for NO conversion to N_2 was 80%at 300 ℃,which was the best among various promoted metals.Design of experiments(DOEs) with Taguchi method was employed to optimize NH_3-SCR process parameters such as NH_3/NO ratio,O_2 concentration,and gas hourly space velocity(GHSV) over Cu-ZSM-5 nanocatalyst at 250 and 300 ℃.Results showed that the most important parameter in NH_3-SCR of NO is O_2 concentration;followed by NH_3/NO ratio and GHSV has little importance.The NO conversion to N_2 of 63.1%and 94.86%was observed at 250℃ and 300℃,respectively under the obtained optimum conditions.
A series of different transition metals (V, Co, Cr, Mn, Fe, Ni, Cu and Zn) promoted H-ZSM-5 catalysts were characterized by X-ray diffraction SEM) and transmission electron microscopy (TEM). The catalytic activity of these catalysts was evaluated for the selective catalytic reduction (SCR) of NO with NH_3 as reductant in the presence of oxygen. The results revealed that the catalytic activity of Cu-ZSM- 5 nanocatalyst for NO conversion to N_2 was 80% at 300 ° C, which was the best among various promoted metals. Design of experiments (DOEs) with Taguchi method was employed to optimize NH 3-SCR process parameters such as NH 3 / NO ratio, O 2 concentration , and gas hourly space velocity (GHSV) over Cu-ZSM-5 nanocatalyst at 250 and 300 ° C. Results showed that the most important parameter in NH_3-SCR of NO is O_2 concentration; followed by NH_3 / NO ratio and GHSV has little importance The NO conversion to N_2 of 63.1% and 94.86% was observed at 2 50 ℃ and 300 ℃, respectively under the optimized optimum conditions.