Interaction behavior in ultrafiltration of nonionic surfactant micelles by adsorption.
Adsorption of nonionic surfactant micelles onto ultrafiltration (UF), membranes was studied. Two homologous series of nonionic surfactants, namely, Tritons (alkylphenol ethoxylates) and Neodols (alcohol ethoxylates), were used to characterize surface properties of two polymeric ultrafiltration membranes with 20,000 nominal cutoff. Particularly, a cellulose acetate and a polysulfone membrane were investigated. Static adsorption experiments were carried out using surfactant solutions at concentrations above their critical micelle concentration. The characterization of surface properties of UF membranes was based on the adsorption behavior of surfactant species. The adsorption extent on UF membranes was affected by the hydrophobicity-to-hydrophilicity ratio mainly determining the interactions developed at the membrane-surfactant species interface. Adsorption experimental data seem generally to fit the Langmuir isotherm model. Atomic force microscopy was used to examine the alteration of the top membrane surface morphology.
Laboratory of Organic Chemical Technology, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 9 Iroon Politechniou, GR-15780 Athens, Greece.
Ioannis
I
Xiarchos
Danae
D
Doulia