Method of obtaining dried terephthalic acid
AssigneesJgc Corporation, Orient Kagaku Kogyo K.K.
InventorsFujio Tsuchiya, Kenzo Yamamoto, Katsunobu Yamaguchi, Akio Okagami
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Abstract
Terephthalic acid produced by oxidizing paraxylene can be obtained in the form of dried powder from the slurry containing terephthalic acid and acetic acid and/or water by using combination of a tubular type heater having at least one heating tube and a separation chamber in which the heating tube(s) open(s) at one end(s) thereof. Critical slurry concentrations for smooth operation are given.
Claims9
A method of obtaining dried terephthalic acid by removing acetic acid and/or water from a slurry containing terephthalic acid and acetic acid and/or water, characterized by feeding the slurry to a tubular type heater having at least one heating tube which opens at one end in a separation chamber to change the slurry to a solid-gas mixture in the heating tube, discharging the mixture into the separation chamber to separate the solid component and the gas component, thus obtaining terephthalic acid in the form of dried powder;
- and terephthalic acid content in the slurry being less than the value "C" defined by the formula:
- C=(2.5.theta..sup.0.4 +66).alpha.+(3.2.theta..sup.0.35 +74)(1-.alpha.)
- wherein C is expressed as % by weight, .theta. is temperature (.degree.C.) of the heating tube, .theta. is molar ratio of water in the slurry medium and (1-.alpha.) is molar ratio of acetic acid in the slurry medium.
Dependencies are inferred from the claim text.