| 초록 |
A study was carried out to attempt the recovery of phosphoric acid from waste etching solutions of acetic, nitric, and phosphoric acid, by using a solvent extraction process. Experimental parameters, such as the concentration of the extractant and the phase ratio, were analyzed. Phosphoric acid was extracted using trioctyl phosphate of the phosphate extractant. The effects of phosphate concentration, stirring time, and speed, on the solvent extraction of the waste etching solution was examined. The extraction behaviors of acetic, nitric, and phosphoric acids were investigated according to the changes of extractant concentration, stirring time, and speed. Experimental results showed that acetic acid and nitric acid could be separated and extracted by using a phosphate-based extractant. The content of the extractant was 50% of the organic phase. The stirring speed and time did not have a significant influence. Acetic acid and nitric acid were completely extracted and separated at seven stages of A / O = 1/3. Phosphoric acid could be recovered from the extraction residue. |
