Adsorption of sorbitan fatty acid esters and a sucrose mono-alkanoate at the nitrobenzene-water interface and its effect on the rate of ion transfer across the interface

✍ Scribed by Takashi Kakiuchi; Yoshikazu Teranishi; Katsumi Niki

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 567 KB
• Volume: 40
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(95)00215-z

✦ Synopsis

Adsorption properties of two non-oxyethylene-type nonionic surfactants, sorbitan fatty acid esters (SF) and a sucrose alkanoate (SA), have been studied at the polarized nitrobenzene-water interface by measuring the double layer capacitance (C,,). Both SF and SA lower C,, in the range of applied potential with no sign of desorption nor of facilitation of ion transfer across the interface. The rate of transfer of tetraethylammonium ion across the interface is not appreciably affected by the presence of surfactant adsorption. Both SF and SA are effective for suppressing convective motions of the solutions in the vicinity of the liquid-liquid interface.