Determination of Iodine in Phosphate Ores by Inductively Coupled-PlasmaMass Spectrometry

A method for the determination of iodine in phosphate ores by inductively coupled plasma mass spectrometry (ICP-MS) was developed. Sample was decomposed by H3PO4-HClO4 and sample solution was adjusted to weak alkaline using ammonia solution. Then the sample solution was directly determined by inductively coupled plasma mass spectrometry (ICP-MS). The detection limit of the method for iodine is 0.33 μg/g and the recoveries are 95.0%～97.4%. The method has been applied to the determination of iodine in National Standard Materials GBW 07210 and GBW 07211 and the results are in agreement with certified values with precision of 2.77%～3.17%RSD