Determination of Acid Number (AN) with Titration and NIR Spectroscopy
WP-053
ja
The acid number (AN) is a measure for the quality of oils and their potential to enhance corrosion. When analyzing fresh, unused oils, the AN is used to ensure the specified quality from the manufacturer, whereas for used oils the AN is determined to observe its increase until a critical level is reached. Although it is generally assumed that the AN correlates to the corrosive potential of the oil, this is not exactly correct, as it is the change of the AN value which indicates this issue. Therefore it is necessary to determine the AN on a regular basis.Several standards already exist to determine AN via titration methods, however it is also possible to measure this parameter via spectroscopic (NIRS) methodology. No matter which technique you choose, Metrohm has you covered with high-performance instruments suitable for these published norms.
The acid number (AN) is an important parameter for assessing the quality and corrosiveness of oils. It indicates the amount of acidic compounds in the oil, which can degrade the oil’s performance and damage costly equipment. The AN can be measured by different methods, such as titration or near-infrared spectroscopy (NIRS). This White Paper presents the principles and advantages of both techniques, as well as the relevant standards and instruments from Metrohm. Ultimately, this provides an overview of the options and considerations for determining the AN of oils using titration or near-infrared spectroscopy (NIRS).