CAJ | 학술논문

采用沉淀法制备磁性γ-Fe2O3脱硝催化剂，通过瞬态动力学方法考察 NH3、O2气体浓度对催化剂选择性催化还原(SCR)脱硝率的影响，在消除内外扩散阻力基础上应用稳态动力学研究方法构建SCR脱硝本征反应动力学模型。实验结果表明：NH3能快速在催化剂表面活性位上吸附活化；NO 的吸附及其活性过渡中间体的形成在 SCR 反应中起控制作用；O2浓度小于1%时，其浓度的提高促进了磁性γ-Fe2O3催化剂SCR反应进行；在试验条件下，磁性γ-Fe2O3催化剂的NO、NH3、O2的反应级数分别为0.41、0、0.27，但当O2浓度>1%时，其反应级数为0，研究得到磁性γ-Fe2O3催化剂SCR表观反应活化能为28.77 kJ/mol。
채용침정법제비자성γ-Fe2O3탈초최화제，통과순태동역학방법고찰 NH3、O2기체농도대최화제선택성최화환원(SCR)탈초솔적영향，재소제내외확산조력기출상응용은태동역학연구방법구건SCR탈초본정반응동역학모형。실험결과표명：NH3능쾌속재최화제표면활성위상흡부활화；NO 적흡부급기활성과도중간체적형성재 SCR 반응중기공제작용；O2농도소우1%시，기농도적제고촉진료자성γ-Fe2O3최화제SCR반응진행；재시험조건하，자성γ-Fe2O3최화제적NO、NH3、O2적반응급수분별위0.41、0、0.27，단당O2농도>1%시，기반응급수위0，연구득도자성γ-Fe2O3최화제SCR표관반응활화능위28.77 kJ/mol。
ABSTRACT:Magneticγ-Fe2O3 catalysts were prepared by precipitation. The effect of NH3 and O2 on selective catalytic reduction (SCR) was investigated through the switching off and on method. And the intrinsic kinetics model for magneticγ-Fe2O3catalyst was built in the absence of internal and external diffusion by the way of steady-state dynamics. NH3 is absorbed and activated quickly on the active sites of catalyst surface; the adsorption of NO and the formation of its active transition species is the rate-determining step of SCR; the SCR reaction is promoted by O2 when it is less than 1%. It is also found that on the test condition the SCR reaction order with respect to NO, NH3, O2is 0.41,0 and 0.27 respectively, but the reaction order with respect to O2is 0 When O2 exceeds 1%.The derived apparent activation energy of magneticγ-Fe2O3 catalysts is 28.77 kJ/mol, which is much lower than the apparent activation energy of Vanadium titanium base catalyst.