In/H-Beta modified by Co3O4 and its superior performance in the presence of H2O and SO2 for selective catalytic reduction of NO with CH4
Jiuhu Zhao, Zhengzhong Wen, Rongshu Zhu, Zhi Li, Ran Ding, Yongji Zhu, Tingkun Gu, Rong Yang, Zhenye Zhu
Abstract
In this paper, In-metal oxide/H-Beta catalysts were synthesized by ion exchange method and In-Co3O4/H-Beta exhibited the highest catalytic activity for the selective catalytic reduction of NOx with CH4 in presence of H2O and SO2. Thus, the synthesis conditions of In-Co3O4/H-Beta were optimized. The results showed that In-Co3O4/H-Beta exhibited excellent catalytic performance and high CH4 selectively when the synthesis was carried out by ion exchange method, the ratio of Si and Al in H-Beta was 25, the ratio of Co3O4 and H-Beta was 5:40, the concentration of ion exchange liquid was 0.033 M and calcination temperature was 500 °C. The NOx removal efficiency was about 87.6 % and N2 selectivity could reach 96.3% in the presence of H2O and SO2. Through a series of characterizations, it was concluded that In-Co3O4/H-Beta owned stable catalyst structure, abundant Brønsted acid sites and the highest ratio of InO+/In2O3 under the optimal synthesis conditions. In addition, the doped of Co3O4 could inhibit the adsorption of sulfate species on the surface of In/H-Beta catalyst, leading to the excellent H2O and SO2 resistance property.