SEPARATION OF OCTYLPHENOL POLYETHER ALCOHOLS SURFACTANTS BY CAPILLARY COLUMN SFC AND HPLC

摘要

Separation of nonionic octylphenol polyether alcohols (OPA) by supercritical fluid chromatography (SFC) and HPLC is described. Using a density programming and a 50-mu m i.d. capillary column, a total of 18 group oligomers was separated. The effects of the operating parameters, such as temperatures of mobile phase, flame ionization detector (FID) and injector, on SFC analysis were investigated. The results demonstrated that the separation efficiency is better when mobile phase temperature is above 100 degrees C, which must be due to the higher volatility of the oligomers. The results also demonstrated that the change of FID temperature from 300 degrees C to 420 degrees C has no effect on the total peak response. The study shows that injector cooling is not necessary when the analyte is in methanol. The total peak response was lower when the injector temperature was changed from 21 degrees C to 10 degrees C. A group of polar oligomers was found in OPA in HPLC analysis, not found in SFC. The result indicates that the polar oligomers present in OPA were not soluble in supercritical fluid carbon dioxide and, therefore, not observed in SFC.