Método alternativo para a determinação do ponto de equivalência da curva obtida no processo de titulação

Abstract

Titration is a technique of qualitative and quantitative analysis, widely used in laboratories in academic level and industries. In most cases, this type of test is done manually, which requires some experience of the analyst for a better interpretation of the end point in the titration. Automating this type of analysis requires financial investment, that in certain situations the laboratory as a whole does not have this feature. Faced with this problem, the objective of this work is to propose an alternative method for determining the end point, and compare their effectiveness with some existing methods, in such a way that produces a result with the best possible approximation of the actual value. For the purposes of understanding and comparing the methods discussed are: geometric methods, numerical and curve fitting. The end point of the titration was estimated for various titrations according to the characteristic of each method. The method proposed by curve fitting is based on a linearization of the titration curve (logistic curve) and starting from empirical data, it is possible to get as reliable result when compared to that obtained by the methods listed above and to the potentiometric titrator.