Promotion effects of plasma treatment on silica supports and catalyst precursors for cobalt Fischer–Tropsch catalysts

Abstract

The glow discharge plasma technique was applied to decorate the silica support and to decompose the precursors of cobalt-based catalysts. The catalysts were characterized by N₂-physisorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), hydrogen temperature-programmed reduction (H₂-TPR), temperature programmed desorption of H₂ (H₂-TPD) and O₂-titration. The results confirmed that plasma decoration would modify both the SiO₂ pore structure and surface properties. Compared with the calcined catalysts, plasma treated samples had a much higher cobalt dispersion and good cobalt reducibility, leading to an apparently improved FTS activity.