Simultaneous determination of chlorite, chlorate, perchlorate and bromate in ozonated saline by using IC-MS

A simple, accurate and reliable analytical method for simultaneous determination of chlorite, chlorate, perchlorate and bromate in ozonated saline by using ion chromatography coupled with triple quadrupole mass spectrometry (IC-MS) has been developed. The use of silver (Ag) and hydrogen (H) OnGuard cartridges and 100-fold dilution were found to be simple and effective for sample pretreatment. Under optimized MS parameters, method validation was convincingly confirmed. A good linearity was obtained with regression correlation coefficients (R-2) larger than 0.999. The mean relative recoveries of chlorite (ClO2-), chlorate (ClO3-), perchlorate (ClO4-), and bromate (BrO3-) ranged from 79.96 to 97.63%. The obtained limit of detection (LOD) was 1.00 mu g L-1 for ClO2-, 0.10 mu g L-1 for ClO3-, 0.04 mu g L-1 for ClO4-, and 0.50 mu g L-1 for BrO3-. Chlorate and bromate were only detected in ozonated samples. In addition, the concentration of chlorate and bromate was in direct proportion to the amount of ozone in saline.