| 摘要 |
PURPOSE:To recover phosphoric acid as the aq. free acid soln. by loading a waste acidic soln. contg. salts and phosphoric acid on a strongly basic anion- exchange resin in the second operating cycle onward and using an inorg. strong acid firstly and water secondly as the developer. CONSTITUTION:A waste acidic soln. contg. salts and phosphoric acid is separated into the aq. salt soln. and aq. acidic soln. by the chromatographic separation technique using a strongly basic anion-exchange resin, and the process is repeated. In this case, the waste soln. is loaded on the anion-exchange resin at least in the second cycle onward, and an inorg. strong acid is used firstly and water secondly as the developer. As a result, the phosphoric acid in the waste soln. is recovered not as an aq. phosphate soln. but as the aq. free acid soln. Since phopshoric acid is recovered as expensive phosphoric acid in the form of the mixture with the inorg. strong acids such as hydrochloric acid, the process greatly contributes to the industrial world. |
