| 摘要 |
The synthesis solution is acidifed, then evaporated to achieve a phase separation, and then the organic phase is evaporated to form a residue which is distilled to yield the acid. A method for processing an optionally partially evaporated aqueous synthesis solution containing at least one 1,3-dioxane carboxylic acid, comprises the following steps : (1) acidifying the synthesis solution ; (2) evaporating the acidified solution until it separates into an upper organic phase and a lower aqueous/salt phase ; (3) separating the organic phase and evaporating to form an essentially anhydrous and/or solvent-free residue; (4) distilling the residue at low pressure and a temperature governed by the b.pt. of the 1,3-dioxane carboxylic acid, to give the acid in pure form as a distillate. |
