| 摘要 |
Aqueous mixtures of succinic, glutaric and adipic acids are separated by contacting the mixture with water-immiscible solvent to give a water to solvent ratio of 0.05 to 2.0, separating into two phases, and recovering adipic acid from the immiscible solvent phase and succinic and glutaric acid from the aqueous phase. The aqueous mixture is particularly, the residue after the crystallization of adipic acid from the oxidation product of cycloparaffins in a two-stage process. The solvents may be aliphatic alcohols with 4-15 carbon atoms and the esters thereof. The immiscible solvent phase is again washed and adipic acid fractionally crystallized from the aqueous stage while the mother liquor is returned to the original aqueous mixture. The succinic and glutaric acids may be recovered in combination from the original aqueous phase, or obtained individually by contacting with a water-immiscible solvent and recovering succinic acid from the resulting aqueous phase and glutaric acid from the solvent phase, preferably by a further extraction with water. |
