| Abstrakt: |
A micro quantity of perchlorate ions is extracted into chlorobenzene with crystal violet. The absorbance maximum of the extract in the organic layer is found to be at 595 mµ. The maximum and the constant extraction was obtained in the pH range of 2–7. In order to ascertain the optimum conditions for the determination of perchlorate ions, various factors have been studied: the effects of the concentration of the dyestuff, the pH of the solution, the standing time of the solution, the times of the extraction, and the presence of diverse ions. The recommended procedure for the calibration curve is as follows: Two milliliters of a crystal violet solution (1×10-3m), 5 mlof a potassium phosphate buffer solution (1 m, pH 5.8), and various volumes (0–10 ml) of a standard perchlorate solution (2×10-5mol/l) are mixed. The mixed solution is diluted to 25 mlwith water. An aliquot (10 ml) of the solution is then poured into a separatory funnel and is shaken for 5 min with 10 mlof chlorobenzene. The absorbance of the organic layer is measured at 595 mµ against the reagent blank solution. Beer’s law is obeyed in the perchlorate range of 10-7–8×106mol/lin the aqueous layer before the extraction. Considerable amounts of chloride, iodate, and sulfate ions do not interfere. |
