Abstract
Alumina-supported NiMoPOx catalysts have been prepared using urea matrix combustion-decomposition method. The effect of urea/metal ratios on the metal oxide dispersion, the conversion of the metal precursor to oxide and the structure and catalyst performance for diesel HDS has been studied. It is shown that the addition of urea adjusts the metal-support interaction, leading to the easy reduction of the metal oxide over the catalyst surface. It also changes the surface cluster of the oxide and the oxide structure. The addition of urea to metal matrix significantly improves the catalytic diesel HDS performance and increases the catalyst stability. The urea to Ni metal ratio of 2 gives the highest sulfur removal rate in the real diesel HDS process.