The total acid number (TAN) is an important quality parameter for engine and hydraulic oils, as it reflects the degree of oil degradation and corrosion potential. Current standard methods for TAN determination, such as ASTM D664, are based on potentiometric titration, which is time-consuming and requires frequent calibration and electrode maintenance. This poster presents a thermometric titration method that overcomes these drawbacks and offers a rapid and reliable way to measure TAN in petroleum products.
Thermometric titration uses a temperature sensor that responds to the exothermic reaction between the acid and the base. The method has excellent reproducibility and accuracy and can be performed in less than a minute per sample. The applicability of thermometric titration is demonstrated for engine and hydraulic oils, and the results are compared with those obtained by the potentiometric method.