Analysis for trace halogens (chlorine, bromine and iodine) and trace halides (chloride, bromide and iodide) is conducted on a Total Organic Halogen (TOX) Analyzer. This instrument heats the sample in a quartz combustion tube to 950ºC in an oxygen atmosphere. During combustion, halogens are converted to halides and oxyhalides that are transported to an absorber solution within a coulometric cell. Halides are then titrated against silver to the potentiometric endpoint. For total halide analysis of the sample, the combustion step is by-passed and the sample is added directly to the coulometric cell for titration.
Note: this test gives aggregate results for total halogens or total halides, it does not provide individual results for each element. If you need individual results, the sample should be analyzed individually for each element.
Sample Preparation Trace Halogens and Halides
For total halogens, samples are weighed into a quartz boat. For total halides, the sample is weighed or transferred through a microsyringe directly to the coulometric cell.
Galbraith’s method is based on industry accepted methods (EPA and ASTM). It also includes additional QC requirements to ensure the accuracy of results. The method name and number is indicated below along with a link to its method summary:
This method is susceptible to interferences from high concentrations of sulfur, which titrate with silver. If your sample contains high concentrations of sulfur, an alternate path is required..
Low ppm values are obtainable by this method. The final LOQ is a function of the mass of sample that can be taken for the analysis. Results below the quantitation limit are reported as a less than value, i.e. <10 ppm. Trace Halogens and Halides
Results are reported in ppm (wt/wt basis) unless another unit is requested. Trace Halogens and Halides