| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for effectively purifying 1, 6-dihydroxy naphthalene free from water of crystallization. SOLUTION: The invention relates to the method for purification of 1, 6-dihydroxy naphthalene by cooling a hot aqueous solution containing crude 1, 6-dihydroxy naphthalene to precipitate crystal of the 1, 6-dihydroxy naphthalene, wherein the method is characterized by the addition of 3-50 wt.%, based on the hot aqueous solution, of inorganic salts to the hot solution and set starting of the precipitation of the crystal at temperature≥40°C. COPYRIGHT: (C)2007,JPO&INPIT
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