A Direct Infrared Method for Determining 4-Methyl-2,6-Ditertiarybutylphenol in Mineral Oil

Abstract

A convenient and rapid direct infrared method for determining 4-methyl-2,6-ditertiarybutylphenol in mineral oil has been developed that uses the 2.74-micron hydroxyl band. The spectrum of the sample is recorded between 2.65 and 2.85 microns to obtain a pair of absorbances from which the phenol concentration is determined. The corresponding phenol-free oil is not needed, and no sample preparation is required when other substances containing the hydroxyl group are absent. The method is accurate to 0.01% phenol; instrument time is about five minutes.