摘要 |
597502 A method of purifying acetic acid containing terpene and terpenoid impurities, provided that the acetic acid is not glacial acetic acid, comprising: (a) combining acetic acid containing terpene and terpenoid impurities, provided that the acetic acid is not substantially dry, water and a suitable organic solvent, which is substantially immiscible with acetic acid and water, to form a separating composite extraction medium wherein the weight ratio of acetic acid: water is at least 1: 1, and said acetic acid supplied to the separating composite extraction medium contains more than 200 ppm terpene and terpenoid impurities, based on the combined weight of acid and impurities only; (b) separating the components of step (a) into an organic phase and an aqueous acid phase, wherein the terpene and terpenoid impurities are concentrated in the organic phase and the aqueous acid phase is purified of terpene and terpenoid impurities, and the purified acid contains less than 50 ppm terpene and terpenoid impurities based on the weight of acid and impurities only; (c) recovering the purified aqueous acid phase; and (d) drying the purified acetic acid.
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