| 摘要 |
Ion-exchange resins and a process employing the resins are provided for separating low molecular weight weak organic acids from liquid mixtures. Exemplary of such acids are those having eight carbon atoms or less such as formic acid, lactic acid, acetic acid, maleic acid, fumaric acid, citric acid and the like. The resins are gel-type, weak-base, anion-exchange resins which are characterized by their being prepared from lightly cross-linked copolymer beads which are subsequently post-polymerization cross-linked in the presence of a Friedel-Crafts catalyst. When functionalized with weak-base exchange groups, the resins exhibit high operating capacity with respect to retention of the weak organic acids. The process may be used to purify, for example, sugar solutions used in preparing foodstuffs like high fructose corn syrups and fruit juices. In another embodiment, the process recovers the weak organic acids from liquid mixtures. |
