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

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 N-2-physisorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), hydrogen temperature-programmed reduction (H-2-TPR), temperature programmed desorption of H-2 (H-2-TPD) and O-2-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.