Study on determination of iodide in pharmaceutical waste water by improved spectrophotometry

By optimizing reaction time and the innovative using of mixed acid which were constituted by arsenious acid,sulfuric acid and sodium,as while as the mixed chromogenic agent which were constituted by ammonium ferrous sulfate and potassium rhodanate to instead of traditional chemical reagent,the method had been greatly ameliorate at operability,controllability,and reduce uncertainty. Under the optimal experiment conditions,the limit of detection for iodide was 5 μg /L,the recovery was 93. 1% ~ 99. 3%. The proposed method was proved to be suitable for the iodide in kinds of waste water.