A study of hydrocarbon SCR(selective catalytic reduction) on Ag/γ-Al2O3 catalyst

Ag/γ-Al2O3 촉매상에서 탄화수소-SCR(Selective Catalytic Reduction) 연구

  • Received : 2004.09.30
  • Accepted : 2005.03.03
  • Published : 2005.04.25

Abstract

Removal of NO contained in automobile exhaust gas was accomplished by the non-selective catalyst reduction method. The catalysts were prepared through loading of a specific amount of Ag into ${\gamma}-Al_2O_3$. The conversion of $NO_x$ was studied by varying the temperatures, $O_2$ concentrations and $SO_2$ concentrations for the prepared catalysts. The influence of the structure of catalyst to $NO_x$ conversion was followed through the analysis of the physical properties of the prepared catalysts. Experiments were conducted on each of the catalysts by varying the reaction conditions to find an optimum condition. The catalyst $Ag/{\gamma}-Al_2O_3$ shows a highest $NO_x$ conversion when the Ag content was 2 wt% and a reaction temperature of about $450^{\circ}C$. and after conducting the experiments, samples of before and after experiments analyzed using XRD, XPS, TPR, and UV-Vis DRS experiments. The result indicated that when Ag oxide content could not be maintained well at high temperatures $NO_x$ conversion decreased.

Keywords

Catalyst;$NO_x$;$Ag/{\gamma}-Al_2O_3$;$SO_2$ concentration

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