Comparison of reduction behavior of Fe 2O 3, ZnO and ZnFe 2O 4 by TPR technique

Abstract

Advanced integrated gasification combined cycle (IGCC) power generation systems require the development of high-temperature, regenerable, desulfurization sorbents capable of removing hydrogen sulfide from coal gasifier gas to very low levels. As a sort of effective desufurizer, such as Fe 2O 3, ZnO and ZnFe 2O 4, it will endure strong reducing atmosphere in desulfurization process. The reduced degree of desufurizer can have an effect on its desulfurization reactivity. In this paper, Fe 2O 3, ZnO and ZnFe 2O 4 were synthesized by precipitation or co-precipitation at constant pH. After aging, washing and drying, the solids were calcined at 800 °C. The reduction behaviors of sample were characterized by temperature-programmed reduction (TPR). It is found that there are two reduction peaks for Fe 2O 3 in TPR, and whereas no reduction peaks for ZnO are found. The reduction process of ZnFe 2O 4 prepared by co-precipitation is different from that of Fe 2O 3. ZnFe 2O 4 is easier to be reduced than Fe 2O 3. The activation energy of reduction process for Fe 2O 3 and ZnFe 2O 4 is obtained at different reduction periods.