Abstract：After the vanadyl sulfate sample was treated by NaOH-H2O2, the acidity of the sample solution was adjusted by acetic acid and the vanadium in it was separated with precipitation by heating in boiling water bath. The content of chloride ion in the filtrate was then determined by silver nitrate turbidimetry. The effect of nitric acid amount, the addition amount of silver nitrate, and determination time, etc. was discussed to determine the optimal determination conditions. It was found that, after the silver chloride turbid liquid formed by silver nitrate and chloride ion was kept in dark for 15 min, the absorbance of chloride ion kept constant at 420 nm, and the content of chloride ion obeyed Beer's law within the range of 0.5-3 μg/mL. The limit of quantification was 0.002%. When the method was applied to determine chloride ion in vanadyl sulfate samples, the results were consistent with those obtained by ion chromatography. The relative standard deviation (RSD, n=8) was less than 5.0% and the standard addition recovery was 99%-102%.
