Study on the structure and properties of alumina support with double pore distribution and hydrodemetallization catalyst

Gamma-alumina support with micron-sized porous was hydrothermally modified with ammonium bicarbonate solutionto prepare the alumina support with double pore distribution, and the alumina was used as the support to prepare the hydrodemetallization catalyst. The structure and properties of the alumina support and the hydrodemetallization catalyst were analyzed by SEM, N₂ adsorption-desorption, TPR, in situ CO adsorption techniques. It was found that after hydrothermal modification, a large number of micron rod-like particles were formed on the surface of alumina support and in micron-sized channels, and the alumina support has a concentrated 10-15 nm channel distribution and a suitable 1-2μm channel content. Compared with unmodified alumina support, the peak temperature of programmed reduction of the hydrodemetallization catalyst was decreased, the relative content of octahedral molybdenum and the Ni-Mo-S activity number were increased, the hydrodemetallization activity and hydrodenitrification activity were improved obviously.