发明名称 |
Process for producing highly pure terephthalic acid |
摘要 |
There is disclosed a process for producing highly pure terephthalic acid by converting a slurry of terephthalic acid crystals in acetic acid solvent which crystals are obtained by liquid-phase oxidation of p-alkylbenzene, into a slurry thereof in water solvent by mother liquor replacement and then subjecting the latter slurry to a catalytic hydrogenation treatment which process comprises the steps of introducing the slurry of terephthalic acid crystals in acetic acid into a mother liquor replacement column at the top portion; forming an accumulation layer of the terephthalic acid crystals at the bottom portion by the sedimentation of the crystals; feeding replacing water sufficient for the formation of upward rising stream of water to the inside of the column at the bottom portion; and withdrawing the accumulation layer of the crystals from the bottom portion of the column. The accumulation layer is kept at a slightly fluidized stable state and is smoothly withdrawn from the bottom of the column by slowly rotating an arm-type agitation blade placed in the layer or by feeding the replacing water dividedly into two trains.
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申请公布号 |
US5684187(A) |
申请公布日期 |
1997.11.04 |
申请号 |
US19960639966 |
申请日期 |
1996.04.29 |
申请人 |
MITSUBISHI GAS CHEMICAL CO., INC.;TOYO BOSEKI KABUSHIKI KAISHA;MIZUSHIMA AROMA CO., LTD. |
发明人 |
OHKOSHI, FUMIO;INARY, MASATO;ZAIMA, FUMIYA |
分类号 |
C07C51/487;C07C51/43;C07C63/26;(IPC1-7):C07C51/42 |
主分类号 |
C07C51/487 |
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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