Optimization of the Spectrophotometry Analysis Conditions of the Permanganate index

Permanganate index (CODmn) is one of the important indicators used to evaluate the pollution level of the water, the current national standard method is the redox titration. The research of measuring permanganate index using adopting the spectrophotometry by using the strong oxidation characteristics of the potassium permanganate. Through research, the selected optimum analysis parameters: detection wavelength 525 nm, potassium permanganate concentration 0.0025 mol/L , sulfuric acid dosage 5.00 mL, heating temperature 90 degrees C and heating time 30 min. Compared with the national standard method, this method would simplify the reaction process, reduce error and guarantee the test accuracy. The evaluation of this test method confirms it has high accuracy and sensitivity, which is also easy to operate and fulfill the online monitoring.