A potentiometric titration for H2O2 determination in the presence of organic compounds

A new method for the quantitative analysis of hydrogen peroxide in the presence of organic substances is described and discussed. The method is based on the potentiometric titration of hydrogen peroxide with sodium hydrogen sulphite and has been successfully applied to the detection and quantification of the remaining peroxide content in the oxidation of glycerol by H2O2. This method has been tested: the linear range covered was between 17.750 and 0.079 mM. The standard deviation for the low range studied (0.234-0.079 mM) was 0.001 mM, and the limit of quantification (LOQ) obtained for the proposed method was 0.02 mM. The acidity of the peroxide solution showed no influence on the developed method and was sufficient to prevent H2O2 decomposition, while neutral or alkaline pH caused partial decomposition of H2O2. The metrology, including accuracy, precision or relative error and reproducibility of the measurements, is discussed.