The preparation of 3.0F-Co3O4 catalyst with “Yardang Landform” structure and its performance for catalyzing N2O decomposition

Abstract

In this work, the 3.0F-Co3O4 catalyst was synthesized by sol-gel method with the assistance of F127 and used for eliminating the N2O pollution from nitric acid plants. Research indicated that the presence of F127 in the preparation process endowed the 3.0F-Co3O4 catalyst with unique “Yardang Landform” microstructure, which possessed a rich number of “edges and corners”. The unique microstructure enables the 3.0F-Co3O4 catalyst to mainly expose highly active (400) and (511) crystal planes. Based on this unique microstructure, the surface active site density for 3.0F-Co3O4 catalyst was 7.62 µmol g−1 m2, which was about 9 times that of Co3O4(CP) catalyst prepared by traditional co-precipitation method. In addition, the 3.0F-Co3O4 catalyst demonstrated high catalytic activity and stability for the reaction in presence of impurity gases. For example, the catalyst can maintain a conversion of more than 60% for N2O at least 10 h in the feed stream of 2000 ppmv N2O/Ar with 5 vol% O2, 100 ppmv NO and 2 vol% H2O at 400 °C and GHSV = 20,000 h−1.