发明授权
- 专利标题: Process for isolation of dicarboxylic acids and hydroxycarboxlic acids
- 专利标题(中): 分离二羧酸和羟基羧酸的方法
-
申请号: US09591479申请日: 2000-06-09
-
公开(公告)号: US06444108B1公开(公告)日: 2002-09-03
- 发明人: Joel David Citron , Michael Robert Samuels
- 申请人: Joel David Citron , Michael Robert Samuels
- 主分类号: B01D6144
- IPC分类号: B01D6144
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.
信息查询