The carbon dioxide decomposition reactions on Ni and Cu-ferrite fine powders

초록

The mechanism of reduction and oxidation on Ni-ferrites, Cu-ferrites and those solid solution powders were investigated for the carbon dioxide(CO2) gas decomposition. The carbon dioxide into carbon or carbon mono oxide has been one of the possible target technologies for the utilization of carbon dioxide and the mitigation of green-house effects. Cu-ferrite showed excellent redox properties compared to those of Ni-ferrite. Cu-ferrite lost its oxygen atoms from the lattice by the H2 reduction at 473K, which was 150K lower than the temperature at which Ni-ferrite did. The reduction of Cu-ferrite at 1073K formed the mixture of metallic Cu, FeO, and Fe, while Ni-ferrite gave Ni-Fe alloy at the same temperature. Reaction of reduced ferrites with carbon dioxidecarbon dioxide oxidized the ferrites by supplying oxygen atoms from carbon dioxide. The oxidation temperature of the reduced Cu-ferrite was 200K lower, and weight recovery was faster than those of Ni-ferrites. The Ni and Cu-ferrite solid solutions were prepared by co-precipitated method and the mechanism of redox behaviors were investigated and a new mechanism for the carbon dioxide decomposition reaction was proposed.