Water content analysis is performed using the Karl Fischer titration technique through the following steps:
Sample Preparation: The sample is weighed or measured and then dissolved or homogenized in an appropriate solvent to ensure a homogeneous mixture.
Titration: The sample is introduced into the Karl Fischer titration vessel, and the Karl Fischer reagent is added. The reagent contains iodine, sulfur dioxide, a base, and a solvent. The iodine reacts quantitatively with the water present in the sample.
Endpoint Detection: The titration is continued until the endpoint is reached. This is typically detected by a color change in the reaction mixture for volumetric Karl Fischer titration or by a coulometric method where the amount of electricity required to generate iodine is stoichiometrically equivalent to the amount of water present in the sample.
Calculation: The amount of water in the sample is calculated from the volume or coulombs of the Karl Fischer reagent used and the known concentration of the reagent.
These steps may vary slightly depending on the specific Karl Fischer titration method and instrument being used.