Preparation method for hydrodemetallization catalyst

The invention provides a preparation method for a hydrodemetallization catalyst. The method comprises the following steps: (1) performing acid treatment and hydro-thermal treatment on pseudo-boehmite; (2) mixing the clay after high-temperature treatment and the treated pseudo-boehmite, forming by nipping, drying and baking the formed matter under low temperature, performing alkali treatment, washing, drying and baking the treated material, thereby acquiring an aluminum oxide carrier; (3) performing hydrothermal carbonizing treatment and then drying, thereby acquiring a carrier containing aluminum oxycarbide; (4) using a hydrogenation active component steeping liquor for steeping the carrier acquired in the step (4), drying and baking the material, thereby acquiring the hydrodemetallization catalyst. The carbon content in the catalyst prepared according to the method provided by the invention is distributed in a gradient form, the reaction between the external active component of the catalyst and the carrier i