Preparation method of bromaminic acid sodium salt and intermediate of bromaminic acid sodium salt and solvent recovery method

The invention discloses a preparation method of bromaminic acid sodium salt and an intermediate of the bromaminic acid sodium salt and a solvent recovery method. The preparation method of 1-aminoanthraquinone-2-sulfonic acid comprises the following steps that (1) in an inert solvent, a sulfonation reaction is conducted on 1-aminoanthraquinone and chlorosulfonic acid; (2) secondly, after the sulfonation reaction in the step (1) is ended, layered extraction is conducted with concentrated sulfuric acid, the upper layer is a solvent organic phase layer, and the lower layer is a material layer containing the 1-aminoanthraquinone-2-sulfonic acid and sulfuric acid. By the adoption of the preparation method of the 1-aminoanthraquinone-2-sulfonic acid, the extraction layering is complete, and the yield of the 1-aminoanthraquinone-2-sulfonic acid is high. Meanwhile, a method of recycling the solvent with water is adopted, the recycled solvent can be directly used for preparation of bromamine acid and sodium slat of the bromamine acid, and the bromamine acid is high in yield.