Ethylenediamine modified Co/SiO2 sol–gel catalysts for non-ASF FT synthesis of middle distillates

Co/SiO2 sol–gel catalysts were prepared in the presence of ethylenediamine under the same pH and characterized to have an insight into the dependence of product distribution on their structures in FT synthesis. Such catalysts prepared at the acid medium possessed high microporosity, which led to a high selectivity for middle distillates in FT synthesis. Furthermore, the activity of catalysts had a volcano-type dependence on the en/Co molar ratios. All those were closely related with the coordination state of Co precursors and their interaction with SiO2.