Potentiometric Titration of Industrial Samples - End-point Detection by Means of Wavelets

摘要

A continuous wavelet transform with a specially defined dedicated mother wavelet is applied for data treatment as a signal-processing tool in a potentiometric titration. The inflection points of the titration curve are localized in one step of the calculations. The imperfection of signal, random noise, or spikes has no influence on the operation of the procedure. The proposed algorithm does not require any prior information about the nature or the type of analyte and/or the shape of the titration curve. Although the optimization of transformation parameters should be done, they may be chosen from a wide interval.rnThe accuracy and precision of the proposed end-point estimation is examined on several simulated curves and instrumental potentiometric titrations. Under normal working conditions, analyte concentrations with variation coefficients between 1% and 5% have been determined. The procedure based on the wavelets provides an objective criterion for the determination of the end point. It can be reproduced and fully automated, thus contributing to a more versatile titration analysis.