Effect of Promoter on Carbon Monoxide Oxidizing Performance of Molded Caialyst Composed of Calcium Aluminate-Silicon Dioxide-Manganese Dioxide

Abstract

We have studied and developed the molded metal oxides catalyst bound by calcium aluminate which is composed of EMD (stand for electrolytic manganese dioxide), AC (stand for alumipa, cement, calcium aluminate), Si0₂ and promoters such as Cub and Fe₂0₃. It has been commercially available as a home-use catalyst. The purpose of the paper is to stud y the molded metal oxides catalyst, especially EMD, and promoters like CuOx and FeOx, bound by calcium aluminate. The relationships among CO conversion efficiency, the molded catalysts composed of EMD-AC-Si0₂-promoter such as CuOx and FeOx, optimum amounts as promoter in molded catalyst, and most suitable calcined temperature of molded catalyst have been investigated. The main results obtained were as follows. 1) The mold ed catalysts composed of EMD-AC and EMD-AC-Si0₂ showect h igh CO conversion efficiency at 200 to 400°C. 2) Verdigris and copper nitrate are suitable for promoter out of copper compounds, but we selected finally the verdigris as optimum promoter, which meet with high CO conversion, mechanical strength of catalyst and reasonable cost. 3) We also studied the iron compounds as promoter such as FeO(OH), Fe(COOH)₂, Fe(OH)₃, Fe₂0₃ and Fe₃0₄, and FeO(OH) is adopted as promoter out of them. 4) The best component for the molded catalyst was EMD: 60, AC: 25, Si0₂: 5, CuCO₃Cu(OH)2. H₂0: 5 and Fe0(OH): 5.