Study On Eu And Ce Modified Iron-Based Catalysts For Fischer-Tropsch Synthesis

The Fischer-Tropsch synthesis(FTS)is the core of indirect coal liquefaction,also an effective way of the clean and efficient utilization of coal and natural gas resources.In this paper,the effects of different loadings of Eu and Ce promoters on iron-based catalysts of FTS were investigated.FeCuEu catalysts were prepared by co-precipitation method.The effect of Eu promoter addition on FeCu catalysts was investigated by N2 adsorption,XRD,H2-TPR and CO-TPD.The addition of Eu inhibited the reduction of iron oxides,facilitated CO adsorption and enhanced CO concentration over the catalysts surface.Under the reaction condition of 325 ?,9000 h-1,1.0 MPa,CO conversion was 96.3%,and olefins selectivity of C2-C4 was 12.9%with 1%Eu loading.FeCuEuSi catalysts were prepared by co-precipitation method.The effect of Eu promoter addition on FeCuSi catalysts was investigated by N2 adsorption,XRD,H2-TPR,CO-TPD and H2-TPD.With the existence of Si,the dispersion of catalysts increased evidently with higher Eu loading.Eu addition improved reduction and promoted adsorption of CO and H2 over the catalysts surface.FeCuCe catalysts were prepared by co-precipitation method.The effect of Ce promoter addition on FeCu catalysts was investigated by N2 adsorption,TEM,XRD,H2-TPR,CO-TPD,H2-TPD,XPS and MES.The addition of Ce enhanced the reduction of Fe2O3?Fe3O4 and inhibited the reduction of Fe3O4?Fe0.Catalysts with proper Ce loading had higher CO adsorbability and stronger Fe-C bond,also had less H2 adsorption and weakened Fe-H bond for the electron donation property of cerium promoter.Under the above reaction condition,CO conversion was 97.2%,and olefins selectivity of C2-C4 was 17.2%with 2%Ce loading.