Effect of Mn on Co/HMS-Mn and Co/SiO2-Mn catalysts for the Fischer-Tropsch reaction

•The Mn was introduced in the supports SiO2 and HMS during the synthesis step.•At low Mn contents, a fraction was incorporated into the framework of the HMS support.•The presence of Mn promoted a “wetting-like” effect of Co on the support surface.•The use of Mn as promoter resulted in an increment in the selectivity toward C5+ compounds.