화학공학소재연구정보센터
Molecular Crystals and Liquid Crystals, Vol.672, No.1, 142-149, 2018
Comparison of Metachromatic Dyes Used for Determination of Surfactants by Means of Photometric Titration
Two thiazine dyes were used for quantitation of anionic surfactants. The analytical procedure consists in titration of surfactant solution with cationic dye, registering absorbance at specific wavelength. Optimal wavelengths are 640nm for the o-Toluidine Blue dye and 666nm for the Methylene Blue dye. The registered absorbance values are dependent on surfactant concentration because of formation of low-soluble ion pairs. Analytical signal is titrant volume needed to reach the previously selected absorbance value. The main advantage of the proposed method is that no toxic chloroorganic solvents are used. The additional advantage is that the spectrophotometric titrations may be carried out in semi-automatic mode.