Method for recovering arsenic from high-concentration arsenic-containing wastewater

The invention provides a method for recovering arsenic from high-concentration arsenic-containing wastewater, which comprises the following steps of: a) mixing the high-concentration arsenic-containing wastewater and concentrated sulfuric acid for the first time, and distilling for the first time to respectively obtain first acid liquor and first arsenic-rich liquor; and b) mixing the first arsenic-rich liquid obtained in the step a) with concentrated sulfuric acid for the second time, and distilling for the second time to respectively obtain second acid liquid and arsenic trichloride. Compared with the prior art, the method comprises the following steps: mixing concentrated sulfuric acid with high-concentration arsenic-containing wastewater, distilling to obtain a first arsenic-rich liquid, mixing the first arsenic-rich liquid with concentrated sulfuric acid, and distilling to obtain arsenic trichloride; the method is simple in process and easy to operate, the used sulfuric acid can be recycled after dehydra