PROCESS FOR PRODUCTION OF 1-AMINOANTHRAQUINONE

摘要

A process for producing 1-aminoanthraquinone, which comprises (a) a step of oxidizing 1-nitronaphthalene in the liquid phase with an acidic aqueous solution containing a ceric ion as an oxidizing agent and separating crystals containing 5-nitro-1,4-naphthoquinone and the acidic aqueous solution containing a cerium ion from the resulting reaction mixture, (b) a step of subjecting the 5-nitro-1,4-naphthoquinone obtained in step (a) to Diels-Alder reaction with 1,3-butadiene in a solvent, precipitating crystals containing the resulting 5-nitro-1,4,4a,9a-tetra-hydroanthraquinone, separating them by filtration, separating and recovering the unreacted 1-nitronaphthalene and the solvent in the filtrate in a separation tower, and recycling 1-nitronaphthalene to step (a) for use as the starting material and re-using the recovered solvent for the Diels-Alder reaction, (c) a step of reducing 5-nitro-1,4,4a,9a-tetra-hydroanthraquinone obtained in step (b), separating crystals containing 1-aminoanthraquinone and purifying them, and (d) a step of electrolytically oxidizing the acidic aqueous solution containing a cerium ion separated in step (a) to convert the cerous ion in the acidic aqueous solution to a ceric ion and recycling the resulting acidic aqueous solution containing a ceric ion to step (a) for re-use as the oxidizing agent.