QUANTITATIVE-ANALYSIS OF POLYETHOXYLATED OCTYLPHENOL BY CAPILLARY SUPERCRITICAL-FLUID CHROMATOGRAPHY

The rapid separation and quantitative determination of oligomers of polyethoxylated octylphenol surfactants was achieve using capillary supercritical fluid CO2 chromatography. The oligomer distribution of all surfactants studied was graphically depicted, and the average ethylene oxide number of each individual surfactant was calculated. Temperature programming was investigated in combination with linear pressure programming to enhance long-chain surfactant analysis. The effect of the variable chromatographic parameters, including temperature, pressure programming ramp rate, and solvents used to prepare surfactant solutions, on the separation of polyethoxylated octylphenols are discussed. The capillary supercritical fluid chromatographic analysis results were validated by comparing them to the values obtained from C1 reversed-phase HPLC analyses.