Simultaneous determination of mixtures of acids by potentiometric titration

Multivariate calibration methods were used for the determination of mixtures of acids by potentiometric titration. The linear titration equation of mixtures of acids was derived and the potentiometric data obtained were processed by multivariate calibration approaches such as class least squares (CLS), principal component regression (PCR) and partial least squares (PLS). These models for multivariate calibration were obtained from the potentiometric titration data of a set of samples with known composition and were then used to predict the concentrations of components in unknown samples. The practical utility of this method was demonstrated for the simultaneous determination of two five-component systems with concentration ranges 2.5 x 10(-4)-1.5 x 10(-3) mol l(-1) and acceptable results were obtained. (C) 1998 Elsevier Science B.V.