Development of an analytical procedure for the measurement of nonionic aliphatic polyethoxylated surfactants in raw wastewater

Abstract

Abstract. An analytical procedure has been developed for determining aliphatic alcohol ethoxylates (AAEs) in raw wastewater. AAEs were isolated by solid-phase extraction on a styrenedivinylbenzene disk. The maximum volume that was processed without plugging of the disk was 20 mL. Then AAEs were desorbed with methanol and, after evaporation to dryness, the residue was analyzed by reversed-phase liquid chromatography coupled to mass spectrometry via atmospheric pressure interface. Two desorption temperatures (ambient and 100 °C), two organic modifiers of the mobile phase (methanol and acetonitrile) and two atmospheric pressure interfaces (electrospray and atmospheric pressure chemical ionization) were tested. The lowest coefficients of variation for replicate measurements were obtained by desorbing AAEs from the extraction disk at 100°C and by using methanol-based mobile phase with atmospheric pressure chemical ionization source for extract analysis. Under these conditions, all the analytes (ranging in size from 10 to 16 alkyl carbons and from 1 to 25 ethoxylate groups) were recovered at more than 70 % and the limit of quantification (signal-to-noise ratio = 10) ranged between 0.05 and 4 µg L -1 .

Analytical characterization of PEG polymers by MEKC

“…For these reasons, a derivatization procedure addressed to add a chromophore or a charge to the oligomers, previous to the separation by CE, was needed. Derivatizing reagents such as 3,5‐dinitrobenzoyl chloride 1, 27, 28, phthalic anhydride 11, 12, 29, PIC 30–32, 1‐naphthylisocyanate 33, 1,2,4‐benzenetricarboxylic anhydride 3 and FMOC‐Cl 34 have been used. In all cases, high temperatures and long reaction times are required, as well as the presence of catalysts.…”

Analytical Methods for Polar Pollutants

“…The chromatographic separation of alcohol ethoxylates (AEOs) by RPLC strongly depends upon the organic modifier used: with a water/methanol gradient, AEOs are separated according to the length of the hydrophobic alkyl chain [178][179][180], whereas a water/acetonitrile gradient also provides some separation according to the number of ethoxy groups [155,180]. Alkylpolyglycosides (surfactants based on sugars and fatty alcohols) have a hydrophobic alkyl chain of 8 to 16 carbons that mediates retardation on RPLC [181,182].…”

Quantification of Binary and Ternary Mixtures of Homologous Nonylphenol Polyethoxylates Using the Potentiometric Sensor Array

“…Then they were desorbed with methanol and, after evaporation to dryness, the residue was analyzed by reversedphase liquid chromatography coupled to mass spectrometry via atmospheric pressure interface. The limit of quantification ranged between 0.05 and 4 mg L À1 [25]. The capillary supercritical fluid chromatographic analysis was applied for surfactant (polyethoxylated octyl-and nonylphenol) quantitation.…”