A STUDY ON THE REDUCTION BEHAVIOR OF SILICA-SUPPORTED IRON AND PLATINUM-IRON CATALYSTS

The reduction behavior of silica supported iron and platinum-iron cata lysts were studied by combined in situ temperature programmed reductio n (TPR)-Mossbauer Spectroscopy (MBS). The results indicated that the T PR profiles of the supported Fe catalysts were different from that of bulk alpha-Fe2O3. There existed an interaction between the Pt and Fe m etals and the SiO2 support for the Pt-Fe/SiO2 catalyst. On the support ed iron-containing catalysts, the Fe3+ species were highly dispersed o n the SiO2 support before reduction. No Fe-0 and Fe2+ in octahedral va cancy were found in the reduction of SiO2 supported iron-containing ca talysts. Addition of Pt to the Fe/SiO2 catalyst could promote the redu ction of the iron species.