Analysis principle:

The 4100TI potassium permanganate index online analyzer adds sulfuric acid and excess potassium permanganate solution to the sample. After digestion at a set temperature for a period of time, organic pollutants and reducing inorganic substances in the sample will be oxidized by potassium permanganate. Then, excess sodium oxalate solution is added to react the remaining potassium permanganate. Finally, the excess sodium oxalate solution is titrated back with potassium permanganate. Calculate the volume of the titration endpoint based on the change in oxidation-reduction potential during the titration process, and calculate the permanganate index value accordingly. The calculation result is expressed in milligrams of oxygen consumed per liter of sample.