The invention discloses a method for recovering
precious metal from a waste aluminum-based catalyst and preparing high-purity
alumina. The method mainly comprises the processes of:
roasting, leaching to remove aluminum by using dilute
sulfuric acid, recovering the
precious metal from
slag from which the aluminum is removed by an
aqueous solution chlorination method, adding
ammonia water into
leachate to precipitate an
ammonium aluminum
sulfate coarse
crystal, recrystallizing, and calcining and decomposing to prepare the high-purity
alumina. The method specifically comprises the following steps of: mixing the finely ground waste aluminum-based catalyst (40mu m) and
ammonium sulfate in a weight ratio of 1:(1.3-1.5),
roasting at the temperature of between 300 and 500 DEG C for 2 to 4 hours, performing
fluidization leaching on a
roasting product by using 1mol / L dilute
sulfuric acid for 2 hours, performing
solid-liquid separation, and recovering the
precious metal from the
slag from which the aluminum is removed by the traditional
aqueous solution chlorination method, wherein the
recovery rate of the precious
metal is over 99 percent; and adding the
ammonia water into the
leachate to regulate the pH value and precipitate the
ammonium aluminum
sulfate coarse
crystal, recrystallizing, and calcining and decomposing to prepare the high-purity
alumina, wherein the purity is over 99.99 percent, and the
recovery rate is over 95 percent. The invention has the advantages that: the process is reasonable, the method is easy to operate, the added value of a product is high,
pollution is light,
mass production is convenient to implement, and the like.