WANG Luyuan, CHENG Xingxing, ZHANG Xingyu, et al. Mechanism of nitric oxides reduction by carbon monoxide over cobalt oxides supported by CeO2 nanorod[J]. CIESC Journal, 2016, (S1): 260-269. DOI: 10.11949/j.issn.0438-1157.20151657.
WANG Luyuan, CHENG Xingxing, ZHANG Xingyu, et al. Mechanism of nitric oxides reduction by carbon monoxide over cobalt oxides supported by CeO2 nanorod[J]. CIESC Journal, 2016, (S1): 260-269. DOI: 10.11949/j.issn.0438-1157.20151657.DOI:
以碱法水热合成径向尺寸6~10 nm的CeO2纳米棒,采用湿法浸渍在纳米棒上负载不同含量的Co氧化物。通过实验探究Co含量改变对脱硝性能的影响原理,实验结果显示浸渍方案为3 g CeO2∶30 ml 10%(质量分数) 硝酸钴溶液时,脱硝效率最高,在NO与CO摩尔比为1∶5,体积空速为30000 h-1,无氧状态下,250℃ 即能达到70%以上的效率。采用氮气吸附、XPS、TEM以及XRD测试不同钴含量催化剂的物化性质,与催化性能结果比对分析后得出Co的添加是通过改变催化剂表面的活性官能团来提高效率,其中Co2O3对于催化CO与NOx进行反应具有较高的效率,提高催化剂中Co2O3的比重可以将高效率温度段降低,CoO在一定程度上对CO与NOx反应具有负面作用,而Co3O4对低温阶段N2O选择性影响较大。
Abstract
CeO2 nanorod was synthesized by a hydrothermal method in alkaline solution and cobalt oxides were loaded on CeO2 via wet impregnation methods. In order to study the effects of precursor concentration
the catalytic performances and chemical-physical characteristics of catalysts were investigated. The results indicated that the optimal precursor concentration was 10% (mass). After systematically comparing chemical-physical properties detected by nitrogen physisorption
XRD
XPS
TEM
with deNOx performance
it can be found that Co2O3 was most effective component in the catalysts and increasing its fraction could greatly promote the deNOx activity. The existence of the CoO had negative effect to the CO and NOx reaction while Co3O4 caused N2O generated at a lower temperature.