Halogens – (Fluorine, Chlorine, Bromine, Iodine)
The halogen analytics is based on the conversion of fluorine, chlorine, bromine or iodine into an analyzable solution. For this purpose, combustion and pyrohydrolysis are used, which are done as tube, Schöniger or Wickbold combustions.
Halogens, which are contained within the combustion products are absorbed by process-depending reagents and converted into fluoride, chloride, bromide or iodide-ions. As detection methods the ICP-AES, ion-sensitive electrodes as well as titrimetric, microcoulometric, and ion-chromatographic measurements are applied.
In the ICP-AES the analyte is detected spectroscopically after exication/ionization in a plasma. The ion-sensitive electrode determines the ion concentration by voltage measurement against a reference electrode. For the titrimetric methods, we have two main approaches availabe. For chlorine and bromine as major or minor component, titrations against standards and color indicators or electrodes are applicable. For detections in the range of traces the microcoulometric titration is applied. Within the ion chromatography, fluoride, chloride, bromide or iodide-ions are separated from other ions and subsequently quantified.