Water in liquids and solids can be determined specifically and selectively, as the determination of water is based on a chemical reaction: SO2 + I2 + 2H2O = H2SO4 + 2HI. Both free (surface adsorbed) and bound (water of crystallisation or water trapped inside the crystal) can be determined. Methanol is used as the solvent, Karl Fischer reagent: HYDRANAL composite, 5 Duration of the titration generally approx. 2 – 5 minutes. The end point is indicated bipotentiometrically at two platinum electrodes
Substances that react with the KF solution themselves, that are difficult to release their moisture or that cannot be introduced into the titration vessel for other reasons can be analysed by thermally driving out their water content in this combustion furnace. The expelled water vapour is transferred through a molecular sieve dried air stream (N2) into the titration cell and titrated there. Shorter titration times can be achieved by increasing the temperature. At the same time, it is guaranteed that the entire water content is expelled. The oven allows temperatures of up to 300°C.