Comparison of methods for accurate end-point detection of potentiometric titrations

7th Brazilian Congress on Metrology

Villela, R.L.A.^1 ; Borges, P.P.^2 ; Vyskoil, L.^3

Acoustics and Vibration Metrology Division, National Institute of Metrology Quality and Technology-Inmetro, Av. Nossa Senhora das Graças, RJ, CEP 50, Duque de Caxias

25250-020, Brazil^1

Chemistry Metrology Division, National Institute of Metrology Quality and Technology-Inmetro, Brazil^2

Slovak Institute of Metrology-SMU, Karloveská 63, Bratislava

SK-84255, Slovakia^3

关键词: Comparison of methods;    Coulometric titration;    End point detection;    Levenberg- Marquardt methods;    Measurement uncertainty;    Potentiometric titrations;    Reference material;    Second derivatives;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/575/1/012033/pdf
DOI  :  10.1088/1742-6596/575/1/012033

来源: IOP

【 摘 要 】

Detection of the end point in potentiometric titrations has wide application on experiments that demand very low measurement uncertainties mainly for certifying reference materials. Simulations of experimental coulometric titration data and consequential error analysis of the end-point values were conducted using a programming code. These simulations revealed that the Levenberg-Marquardt method is in general more accurate than the traditional second derivative technique used currently as end-point detection for potentiometric titrations. Performance of the methods will be compared and presented in this paper.