In situ XAFS Analysis for Thermochemical Conversion Process of CoCl2 on SiO2

Abstract

The thermochemical conversion processes, in which CoCl2 supported on silica is reduced to Co(0) by gaseous H2 and Co(0) is chlorinated to CoCl2 by gaseous Cl2, were analyzed by means of in situ XAFS method. It was found that both the reduction and the chlorination process between CoCl2 and Co(0) proceed in a single step. The temperature of reduction of CoCl2 is lower than that of CoO, and the temperature of chlorination of Co(0) is higher than that of oxidation. The results indicate that there are differences in reactivity in conversion depending on the type of anion.