Preparation and characteristics of ferrite catalysts for reduction of CO 2

Abstract

To reduce CO 2 gas, high specific surface and high activity of (Mn x Zn 1− x )Fe 2O 4 and (Mn x Ni 1− x )Fe 2O 4 nano-sized powders were synthesized by the hydrothermal process and used as catalysts. Effects of the composition of synthesized ferrites, the activated time of the catalysts, and the flow rate of carbon dioxide on the decomposition of carbon dioxide were investigated. The crystalline Mn–Zn ferrite catalysts with 21–29 nm nano-scale particle size and 73–143 m 2 g −1 specific surface area were synthesized by hydrothermal process at 150 °C for 2 h. The (Mn 0.33Zn 0.67)Fe 2O 4 catalyst shows the best CO 2 decomposition performance after reduction in H 2 at 300 °C for 4 h. The crystalline Mn–Ni ferrite catalysts with 18–24 nm nano-scale particle size and 107–153 m 2 g −1 specific surface area were synthesized by hydrothermal process at 140 °C for 2 h. The (Mn 0.67Ni 0.33)Fe 2O 4 catalyst shows the best CO 2 decomposition performance after reduction in H 2 300 °C for 2 h. The Mn–Zn ferrite showed a better CO 2 decomposition efficiency than that of Mn–Ni catalyst with the same Mn content.