猪粪生物质炭低温SCR催化剂制备及其性能研究

The preparation of low temperature SCR catalysts from swine manure biochar and its properties

利用猪粪生物质炭制备了SM700、SM700A和Mn/SM700A三种催化剂,考察了猪粪生物质炭催化剂的低温SCR脱硝性能,分析了硝酸处理和负载Mn对催化剂性能的影响,采用多种方法表征了不同催化剂的物理化学特性。结果表明:与SM700相比,SM700A的比表面积和总孔容增加,平均孔径和灰分含量降低;负载Mn后,催化剂的比表面积和总孔容进一步增大。Mn/SM700A的NH_(3)-SCR活性最高,150℃时的氮氧化物转化率、氮气选择性和氨气消耗率分别为63%,97%和77%。与SM700A催化剂相比,Mn/SM700A催化剂的表面吸附氧的含量明显增多,O_(α)/O_(β)显著增加;负载的Mn离子在催化剂表面分散均匀,Mn^(4+)/Mn^(3+)具有较强氧化还原能力,从而促使Mn/SM700A表现出较高的催化活性。

Three kinds of catalysts,SM700,SM700A and Mn/SM700A,were prepared from swine manure biochar to study their SCR performance at low temperature.The effects of nitric acid treatment and Mn loading on the performance of the catalysts were analyzed.The physicochemical properties of the catalysts were studied by various characterization methods.The results showed that compared with SM700,the specific surface area and total pore volume of SM700A increased,while its average pore size and ash content decreased.When loaded with Mn,the specific surface area and total pore volume of SM700A increased more obviously.Mn/SM700A had the highest activity for NH_(3)-SCR with 63% NO_(X) conversion,97% N_(2) selectivity and 77% NH_(3) consumption at 150℃.Compared with SM700A,the adsorbed oxygen content on the surface of Mn/SM700A catalyst and O_(α)/O_(β) increased significantly.The Mn ions on the surface of Mn/SM700A catalyst were extremely dispersed,and Mn^(4+)/Mn^(3+) had strong redox ability.Therefore,Mn/SM700A showed high catalytic activity for NH_(3)-SCR.