Sorption of Sodium Dodecyl Sulfate on Amberlite XAD-2 Resin

TLDR: In this article, the authors described the high affinity of SDS for XAD-2 copolymer over a wide pH range and the distribution of humic acid and SDS in fractions of the column eluate.

Abstract: Among the members of the nonionic macroporous Amberlite XAD series, the styrene-divinylbenzene copolymer XAD-2 and methacrylate-based copolymer XAD-8 have been most commonly used for the preconcentration of aquatic humic substances.'-4 They collect humic and fulvic acids more selectively than macroreticular anion exchangers such as diethylaminoethyl (DEAF)-celluloses and DEAE-Sephadex A-25.6 The desorption recovery, however, is often poor, probably because of the presence of irreversible sorption sites, especially when microgram amounts of humic acid are desorbed from the XAD-2 resin.' Previously, we proposed the use of sodium dodecyl sulfate (SDS) for the enhancement of desorption efficiency.' The function of SDS and its behavior on the resin were not clear, however. The present communication describes the high affinity of SDS for XAD-2. Milligram quantities of SDS were strongly sorbed on the resin over a wide pH range. The distribution of humic acid and SDS in fractions of the column eluate was also studied.