Simultaneous Measurements of Arsenic, Bromine, and Iodine in Coal and Coke by Inductively Coupled Plasma-Mass Spectrometer
Abstract Using high pressure and closed microwave digestion technology, the imports and exports of coal and coke samples from different countries were digested quickly with mixed acids of nitric acid, hydrofluoric acid, and hydrogen peroxide solution, with the help of Inductively Coupled Plasma Mass Spectrometer (ICP-MS), a method was established for simultaneous determination of trace elements, such as, arsenic (As), bromine (Br) and iodine (I) in coal and coke. The influence of the medium of nitric acid and other acids on the determined elements was researched. The unstable mass signal of bromine and iodine on account of different valencies could be made stable by adding sodium persulfate. And the silver ion could catalyze and accelerate the reaction mentioned earlier. High memory effect of halogen was effectively decreased by a washing step with neutral mixed lotion. The low detection limits were in the range of 0.1–5.0 μg l−1 with relative standard deviations of 1.5%–12.0%, and the recoveries were in the range of 80%–106.7%. The analysis results were satisfactory.