Title of article :
Effects of La2O3-doping on physicochemical surface and catalytic properties of nickel and manganese oxides supported on alumina Original Research Article
Author/Authors :
Nagi R.E Radwan، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2004
Abstract :
The effects of doping of Al2O3-supported nickel and manganese oxides with La2O3 on their surface and catalytic properties were investigated using nitrogen adsorption at −196 °C, the oxidation of CO by O2 at 150–200 °C, and the decomposition of H2O2 at 30–50 °C. The dopant concentration was varied between 1.0 and 6.0 mol%. Pure and variously doped solids were prepared by wet impregnation method using finely powdered Al(OH)3 solid followed by treating with different amounts of lanthanum nitrate. The lanthanum nitrate-treated were divided into two portions. The first portion was treated with a fixed amount of nickel nitrate dissolved in the least amount of distilled water. The second portion was treated with a known amount of manganese nitrate. Pure and doped solids were calcined at 400–700 °C. The results obtained revealed that the doping process of the investigated solids decreased the degree of crystallinity and particle size of both NiO and Mn2O3 phases. La2O3-doping of investigated systems increased their catalytic activities towards CO-oxidation by O2 and H2O2 decomposition to an extent proportional to the amount of dopant added. The doping process did not modify the activation energy of the catalyzed reaction but increased the concentration of catalytically active constituents taking part in the catalytic processes without changing their energetic nature.
Keywords :
Nickel oxide , Manganese oxide , La2O3-doping , CO-oxidation , H2O2-decomposition , Alumina-support
Journal title :
Applied Catalysis A:General
Journal title :
Applied Catalysis A:General