发明名称 |
Method for separating and purifying catechol mixtures |
摘要 |
An extractive distillation process using a high boiling polyol such as glycerol is employed for separating high purity catechol, 3-methylcatechol and 4-methylcatechol from a high boiling, pitch-like dihydric phenol fraction. Fractional distillation first separates an impure overhead mixture of the catechol and 3-methylcatechol and an impure 4-methylcatechol bottoms. The impure overhead is extractively distilled to remove impurities and then extractively distilled again to separate the catechol and 3-methylcatechol. This produces a pure overhead of 3-methylcatechol and a bottoms of catechol and polyol which is distilled to recover the catechol and recycle the polyol. The impure 4-methylcatechol is distilled to remove residual material and then extractively distilled to remove impurities. The resulting mixture of 4-methylcatechol and polyol is distilled to recover the pure 4-methylcatechol and to recycle the polyol.
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申请公布号 |
US5679223(A) |
申请公布日期 |
1997.10.21 |
申请号 |
US19950490780 |
申请日期 |
1995.06.15 |
申请人 |
DAKOTA GASIFICATION COMPANY |
发明人 |
DUNCAN, DAVID H.;BAKER, GENE G.;MAAS, DANA J.;MOHL, KEVIN M.;KUHN, ALFRED K. |
分类号 |
B01D3/40;C07C37/68;C07C37/74;C07C37/80;(IPC1-7):B01D3/40 |
主分类号 |
B01D3/40 |
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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