Method for purifying lead electrolytic refining waste liquid of methanesulfonic acid system

The invention provides a method for purifying lead electrolytic refining waste liquid of a methanesulfonic acid system, and belongs to the technical field of non-ferrous metal hydrometallurgy. The method comprises the following steps: firstly, adjusting the pH value of the lead electrolytic refining waste liquid to 1-3 to obtain an adjusted liquid; adding sulfuric acid to precipitate Pb < 2 + > ions in the regulating liquid in the form of PbSO4, and taking lead-containing filter residues after liquid-solid separation as lead smelting raw materials; oxidizing Sn < 2 + > ions into Sn < 4 + > ions in the obtained filtrate by using an oxidizing agent to obtain an oxidized solution; adding a calcium precipitant into the oxidation liquid, precipitating Sn < 4 + > ions in the oxidation liquid in the form of CaSnO3, carrying out liquid-solid separation to obtain tin-containing filter residues as a tin smelting raw material, carrying out ion exchange adsorption deep purification and impurity removal on the tin-removed