Improved olefin selectivity during CO hydrogenation on hydrophilic Fe/HAP catalysts

The hydrophilic/hydrophobic properties of catalysts greatly influence product distribution by tuning the secondary reactions during Fischer–Tropsch synthesis. Studies have confirmed that hydrophilic modification can inhibit secondary reactions. Herein, hydroxyapatite (HAP)-supported Fe catalysts (Fe/HAP) were prepared using an impregnation method. The effect of the catalyst surface properties on the product distribution in CO hydrogenation was studied. The surface hydroxyl groups on Fe/HAP promoted the growth of carbon chains and improved olefin selectivity. The addition of Na as a promoter to Fe/HAP suppressed the formation of undesirable CH 4 , further improving the selectivity for light olefins and C 5 + hydrocarbons. Compared with Fe 2 O 3 , Fe/HAP showed lower CH 4 selectivity (15%) and higher C 5 + selectivity (45%). Meanwhile, the Fe/HAP -Na catalysts with a higher selectivity of light olefins (with an O/P ratio reaching 4.51).