The Use of Ethanol as an Alternative Solvent to Replace 2-Propanol in the Determination of Total Acid Number in Lubricant by Potentiometric Titration

Abstract

In determining the quality of lubricant, acid content affects the quality of the lubricant. The acid content in the lubricant can be determined by using ASTM D664 Standard Method to determine Total Acid Number. The purposes of this research are to obtain the optimum ratio of a solvent mixture of Toluene and Ethanol to determine the Total Acid Number using the Potentiometric titration method and set the value of its accuracy and precision. This research aims to compare the value of the total acid number of the modified method to the standard method (ASTM D664). The modified method in this research uses toluene and ethanol, with ratios 70 percent: 30 percent. Kolmogorov Smirnov normality test shows that both methods produce normal data, and based on the t-test result, it is showed that both methods produce the results that are not significantly different. Based on the measurement of accuracy and precision, the method generates accurate and precise data. From the overall result, it can be concluded that the solvent mixture of Toluene and Ethanol with ratios 70 percent: 30 percent, can be used as an alternative solvent mixture to replace the solvent mixture in ASTM D664 Standard Method.