1-Nitroanthraquinone → 1-Aminoanthraquinone

Participants

Reaction Steps

5,500 Parts of water was added to a mixture of 200 parts of the nitroanthraquinone (98.0% 1-nitro content) used in Example 4 and 400 parts of 32% sodium sulfide and the mixed solution was heated from room temperature till boiling by spending 70 minutes. A part of the reaction mixture was sampled out and the heating was continued until substantially no unreacted nitro component became detectable by gas-chromatography. Approximately 3 hours was required for this treatment. Thereafter the reaction mixture was cooled to 70° C., filtered, sufficiently washed and dried to obtain 171 parts of 1-aminoanthraquinone. The purity of 1-aminoanthraquinone as determined by gas-chromatography was 98.1%, and the yield of 1-aminoanthraquinone from 1-nitroanthraquinoen was 97.1%. The thus obtained 1-aminoanthraquinone crystals were the substantially same size as those obtained in Referential Example 1, and because of poor filterability, a great deal of time and labor were required for separating them from waste water of reduction.

Provenance & Evidence