Acid value (degree) is one of the important control indicators in the refining process. With the increase of heavy oil, the acidity becomes stronger, and there is an urgent need for a product that can quickly and accurately measure the acid value or acidity of petroleum products. Infrared spectroscopy absorption method is a classic fast analysis method. It is an analytical measurement technology that integrates spectral measurement technology, chemometrics, and computer technology, which can quickly and quantitatively analyze samples.

·Principle

The determination of acid value (degree) of petroleum products essentially measures the content of organic acids, which are called carboxylic acids. These organic acids mainly exist in the form of dimers in petroleum products, so the hydroxyl content can be used to characterize the acid value in oil. The known dimer hydroxyl absorption peaks are mostly broad peaks.