发明名称 |
Process for isolation of dicarboxylic acids and hydroxycarboxlic acids |
摘要 |
A first process involves the partial electrodialysis of a dialkali metal salt of an aromatic hydroxycarboxylic acid or a dicarboxylic acid to produce the approximate monoalkali metal salt and the alkali metal hydroxide. The monoalkali metal salt is then treated with an acid such as a bisulfate to recover the aromatic hydroxycarboxylic acid or dicarboxylic acid. The resulting inorganic salt such as sodium sulfate may then be electrolyzed to sodium bisulfate and NaOH. A second process involves the electrodialysis at elevated temperatures of a (di)alkali metal salt of p-hydroxybenzoic acid produce free p-hydroxybenzoic acid and the alkali metal hydroxide. These are efficient and economical methods for recovering the acid and alkali metal hydroxide values, as well as the parent organic compound, from these dialkali metal salts.
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申请公布号 |
US6444108(B1) |
申请公布日期 |
2002.09.03 |
申请号 |
US20000591479 |
申请日期 |
2000.06.09 |
申请人 |
E. I. DU PONT DE NEMOURS AND COMPANY |
发明人 |
CITRON JOEL DAVID;SAMUELS MICHAEL ROBERT |
分类号 |
B01D61/44;C07C51/02;C07C51/15;C07C65/03;F26B11/12;F26B21/14;(IPC1-7):B01D61/44 |
主分类号 |
B01D61/44 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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