A series of MgFeMn-HTLcs (hydrotalcite-like compounds) precursors with different Mg/Fe/Mn molar ratios were prepared by coprecipitation-hydrothermal method

which were then calcined and modified with K impregnation to be used as catalysts for light olefin synthesis from CO hydrogenation. The catalysts were characterized by XRD

SEM

TG

N2 adsorption-desorption

H2-TPR and XPS techniques. The results showed that MgFeMn-HTLcs precursors had typical layered structures of hydrotalcite and reduced crystallinity by Mn addition. After calcination

MgO was only detected from Mg-Fe precursors whereas Mg2MnO4

MgO and MgFe2O4 were co-existed from Mg-Fe-Mn precursors. After CO hydrogenation

main phases were MgCO3 and FeCO3

accompanied by formation of FeO-MnO and little FexCy. Mn addition further promoted Fe dispersion and increased reduction from Fe2O3 to Fe3O4

compared to those of K/Mg-Fe catalysts. With Mn increase and its electron donating effect

binding energies of Fe 2p were shifted to lower values. In CO hydrogenation

all prepared K/Mg-Fe-Mn catalysts showed high activity and C2=-C4= selectivity. O/P value of 5.20 and C2=-C4= fraction of 43.03% were achieved with low methane selectivity over K/3Mg-1Fe-2Mn catalyst.