Synthesis of ternary Ce2O3/La2O3/Fe3O4 oxides as a potential catalyst for SO2 reduction by CH4 to sulfur

In this study, ternary mixed metal oxide (Ce2O3/La2O3/Fe3O4) catalysts were synthesized for reduction of SO2 to sulfur by CH4. The response surface method (RSM) was used to optimize the synthesis conditions. The XRD, FESEM, BET, BJH, EDX and NH3-TPD analyses were performed to characterize the synthesized catalysts. The optimum conditions were obtained for an activated catalyst with 8 wt% La, 16 wt% Fe, and calcination temperature of 650°C. The highest surface area was found to be 71.7 m2.g-1. The validation tests proved that the predicted model was well fitted with the experimental data. Furthermore, the SO2 conversions were compared at various temperatures (550-800 °C) and it was found that the highest reactivity was found for optimum Ce2O3/La2O3/Fe3O4 catalyst. The highest SO2 conversion was found to be 93% at 800 °C. The catalytic results showed that optimum ternary Ce2O3/La2O3/Fe3O4 catalyst had a better performance compared to pure cerium oxide.