Manganese promotion in cobalt-based Fischer-Tropsch catalysis

ABSTRRACT The effect of Mn addition on the catalytic performances of Fischer-Tropsch synthesis was investigated using a series of Co/TiO 2 catalysts prepared by two different preparation methods; incipient wetness impregnation (IWI) and homogeneous deposition precipitation (HDP). Mn was loaded using two different procedures in order to investigate its interaction with Co and TiO 2 . Several characterization techniques, mainly XRD, XPS and TPR, were used to elucidate the Co oxidation state and dispersion and to estimate the Mn location. Fischer-Tropsch synthesis carried out at 1 bar of pressure showed an improvement of the catalytic performance in the Mn-promoted HDP catalyst, whereas no promotion effect was found in Mn-promoted IWI catalyst. This difference can be explained by a different Co-Mn interaction