Many organic substances in natural waters are amphipathic; i.e., they contain both a hydrophobic and a hydrophilic moiety. To assess the adsorptive behavior of such substances and to appreciate the factors that influence the distribution between particles and water, we need to understand how these substances interact with polar or nonpolar interfaces. To gain such an understanding, the adsorption of fatty acids of various chain lengths has been investigated on two model surfaces: (1) on a Hg electrode and (2) on δ-Al₂O₃ particles. While hydrophobic expulsion dominates the adsorption on the nonpolar Hg surface, the adsorption of short-chain fatty acids (<8 carbon atoms) on the surface of hydrous Al₂O₃ is characterized by specific coordinative interaction. Phase-selective polarography is a convenient tool to measure the extent and kinetics of adsorption of those amphipathic substances that become adsorbed primarily because of hydrophobic expulsion.
No takes yet. Share an insight, caveat, or question.
Ulrich et al. (1988) studied this question.