Method for separating and recovering titanium dioxide from metal tailings

The invention discloses a method for separating and recovering titanium dioxide from metal tailings. The method separates and extracts titanium, aluminum, iron and other components to obtain titaniumdioxide, a water purifying agent and other high-added-value products while effectively reducing the stockpiling amount of the metal tailings, thereby realizing efficient recovery and utilization of the metal tailings. The method mainly comprises the following steps: (a) uniformly mixing the metal tailings and mixed acid (formed by mixing oxalic acid, citric acid and sulfuric acid) according to a solid-to-liquid ratio of 1: (5-50) g/ml, conducting leaching, and performing filtering to obtain an acid leaching solution A and acid leaching residues; (b) adding sulfuric acid into the acid leachingsolution A, carrying out hydrolyzing and filtering to obtain a precipitate and a filtrate B, and drying and calcining the precipitate to obtain titanium dioxide; (c) adding mixed acid into the filtrate B, and repeating the ste