Preparation method of mesoporous nickel-magnesium-aluminum oxide with high specific surface area

The invention mainly relates to a preparation method of a nickel-magnesium-aluminum composite oxide with a high specific surface area, and belongs to the technical field of inorganic nano materials. The preparation method comprises the following steps: firstly, mixing aluminum salt, nickel salt and magnesium salt according to a certain proportion, i.e. the mole ratio of the aluminum salt to the nickel salt to the magnesium salt being (0.1-1) to (0.1-1) to 1; then dissolving in a certain amount of deionized water, so as to prepare a stock solution; dropwise adding an 1-4 mol/L ammonium carbonate solution into the stock solution at 30 to 90 DEG C, and controlling the mole ratio of ammonium carbonate to aluminum ions to be (1.0-1.3) to 1; transferring colloid formed after dripping into an oven and drying for 12 to 24 hours at 80 DEG C to 100 DEG C; roasting for 10 hours at 400 DEG C to 700 DEG C at a heating rate of 10 DEG C/min; and grinding, so as to obtain nickel-magnesium-aluminum composite oxide with the su