EFFECT OF PREPARATION CONDITIONS ON THE CATALYTIC OXIDATION OF NO OVER Mn-Fe-O_x

摘要

The manganese and ferric oxides (Mn-Fe-O_x) catalysts were prepared by organic solvent method which mixing the aqueous solutions of Mn- and Fe-salts, and the calcinations of the product thereof. The catalytic activities of the prepared catalyst were investigated on the oxidation of NO. The effects of the preparation conditions, such as washing solutions, order of feeding the reactants, the methods of combining the reactants, and the precursors, on NO-conversion are discussed in this study. The results show that the Mn-Fe-O_x catalyst with quasi-crystalline structure has the notable activity for the NO-oxidation. In our work, more than 90% NO could be converted to NO_2 over the Mn-Fe-Ox catalysts at 125 at a space velocity of 45000 h~(-1). The characterization of the catalysts was carried out by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The characterized physicochemical properties of the prepared catalysts showed that the specific crystal structure and the microstructure of the catalysts were greatly affected by the prepared conditions, especially by the combination-methods, and precursors.