Hydrotreating of Coker Light Gas Oil on MCM-41 Supported Nickel Phosphide Catalysts

Siliceous MCM-41-supported nickel phosphides with a Ni/P atomic ratio of 2 and 0.5 were prepared by Temperature programmed reduction method. The phase purity and structural/surface properties were studied by X-ray diffraction and N-2 sorption measurements respectively. X-ray diffraction (XRD) analysis of the passivated catalysts confirmed the presence of Ni2P and Ni12P5 in all catalysts prepared from oxidic precursors. Supports and catalysts were thoroughly characterized by using other techniques also; such as EDAX, SEM, and TEM. Results from low angle XRD measurements confirm the presence of hexagonally ordered mesoporous structure in MCM-41 material. Hydrotreating experiments were conducted under industrial conditions using Coker light gas oil (CLGO) as feed which contains 2,439 ppm nitrogen 23,420 ppm sulfur respectively. The activities with high Ni/P ratio (Ni/P=2 or Ni12P5/MCM-41 catalyst) exhibited higher hydrotreating activities than the catalysts with lower Ni/P ratio (Ni/P=0.5 or Ni2P/MCM-41 catalyst) due to higher activity of Ni12P5 phosphides. The ratios of HDN over HDS activities are much higher over both phosphide catalysts than over the NiMo reference sample, due to the higher dispersion of metals in the former one. It was confirmed from this research work that Ni12P5/MCM-41 has shown very promising catalytic activity for hydrotreating of Coker light gas oil than the NiMo catalysts prepared by conventional method.