Selective recovery method for valuable metal from spent SCR catalyst using alkali fusion

摘要

According to the present invention, a method of selectively recovering a valuable metal from a waste denitrification catalyst using alkali fusion comprises: (a) a step of adding an alkali metal to a waste denitrification catalyst, and mixing the alkali metal and the waste denitrification catalyst to perform alkali fusion to create a calcination product; (b) a step of water-leaching the calcination product to recover an alkali leach solution and a residue; (c) a step of adding a precipitator to the alkali leach solution and agitating the precipitator and the alkali leach solution to allow calcium metavanadate (Ca(VO_3)_2) or calcium tungstate (CaWO_4) to precipitate to recover the calcium metavanadate or the calcium tungstate; and (d) a step of acid-hydrolyzing the recovered calcium tungstate to manufacture tungstic acid. As such, vanadium and tungsten is able to be recovered at high efficiency by adding an excess amount of alkali metal to a waste denitrification catalyst, and calcinating the alkali metal to add a precipitator of a water-leached leach solution and adjusting a speed of reaction.