The antimony-rich layer created by thermal-spreading of Sb2O3 on Fe2O3 surface

The thermal-spreading of Sb2O3 was found to be an easy way to create an antimony-rich surface layer on metal oxides, this clean process could be used to produce or to activate the antimony-based catalysts without generation of liquid or gas waste. In prepared mixtures of Sb2O4 and Fe2O3, the antimony spreading over Fe2O3 surface has been investigated by SEM and XPS, etc. A model is proposed to determine the antimony concentration in the surface layer of Fe2O3 particles, and it is found to increase dramatically after antimony thermal-spreading treatment, e.g., in the studied mixtures of Sb2O4 and Fe2O3 with a Sb/Fe atomic ratio of approximately 0.3, the SbSb+Fe×100% achieves up to 90% in the surface layer of Fe2O3.