The invention discloses a method for recovering metallic
tin from aluminum-
tin alloy waste, which comprises the following steps: electrochemically dissolving the aluminum-
tin alloy waste in a
sulfuric acid solution with the
mass concentration of 20-30%, carrying out electrolytic deposition on tin on a
cathode to recover metallic tin with the purity of more than 99%, leaving aluminum in an
electrolyte in the form of aluminum
sulfate, and after
electrolysis is finished, recovering the metallic tin from the aluminum-tin
alloy waste. The method comprises the following steps: adding
metal aluminum sheets or aluminum
powder into an aluminum
sulfate solution to replace residual
metal impurities such as tin and
nickel in a reaction solution, filtering to obtain a primary filtrate, adding
activated carbon to adsorb and remove organic impurities such as oil stains to obtain a secondary purified solution, and carrying out
evaporation concentration, cooling
crystallization and other steps on the secondary purified solution to obtain aluminum
sulfate octadecahydrate. The aluminum sulfate octadecahydrate can meet the requirements of water purifying agents and
nickel-
cobalt-aluminum-
lithium battery raw materials, compared with the prior art,
metal aluminum and metal tin in the aluminum-tin alloy waste can be thoroughly separated, the purity of the recycled metal tin is high, the quality of byproduct aluminum sulfate is good, high economic value is achieved, and the whole process is small in
pollution and quite
environmentally friendly.