Promotion of Mn Doped Co/CNTs Catalysts for CO Hydrogenation to Light Olefins

Abstract

AbstractWith various contents, Mn was introduced into carbon nanotubes (CNTs) supported cobalt catalysts and the obtained Mn‐Co/CNTs catalysts were investigated for CO hydrogenation to light alkenes and characterized by N2 adsorption, X‐ray diffraction (XRD), X‐ray photoelectron spectra (XPS), H2 temperature programmed reduction (TPR), CO temperature programmed desorption (TPD) and transmission electron microscope (TEM). The results indicate that the addition of a small amount of Mn (0.3 wt%) to CNTs‐supported Co catalyst significantly increased the selectivity of C2–C4 olefins and decreased the selectivity of CH4. However, with further addition of Mn to the cobalt catalysts, the CH4 selectivity decreased obviously along with the increase of the C5+ selectivity. Compared with the unpromoted catalysts, the Mn‐promoted cobalt catalysts increased the C2–C4/C20–C40 molar ratio.