| 摘要 |
<p>A method comprising the steps of (a) forming a suspension of diacetyl rhein in a mixture of an organic solvent and water; (b) adding a tertiary amine; (c) adding an alkali metal or alkaline-earth metal acid salt to the resulting solution; (d) performing hydrolysis in a weakly acidic medium; and (e) recovering the purified diacetyl rhein by filtration.</p> |
