N_2O在锰系低温催化剂上的生成途径

Formation Path of N_2O with Low-Temperature Manganese Catalyst

实验对比了由浸渍法、共沉淀法以及溶胶凝胶法制备的锰系低温催化剂在选择性催化还原(SCR)反应中的差异,发现溶胶凝胶法制备的催化剂在整个测试区间内都具有最高的脱硝效率,但是也有最多的N2O生成.针对溶胶凝胶法,进一步研究了N2O在SCR过程中的生成情况.发现N2O主要来源于NH3的直接氧化以及NH3和NO的反应,后者为N2O的主要生成途径.添加Ce、V后,随着反应温度升高,NH3的直接氧化逐步成为N2O主要来源.

The experiments were conducted to compare low-temperature manganese catalysts prepared by different methods in selective catalytic reduction （SCR） reaction. Results showed that the catalyst prepared by sol-gel method not only had the highest deNOx efficiency but also generated the largest amount of N2O. In addition, further experi- ments showed that the production of N2O was primarily controlled by two paths： the oxidation of NH3 with O2, and the direct reaction between NO and NH3 in which the latter was the main producer. With the addition of Ce and V, the former gradually played a dominant role in the N2O formation with the increasing temperature.