The permeability coefficients K for permeation of air through Newton black foam films (bilayer films) from sodium dodecyl sulfate plus sodium chloride aqueous solutions have been measured. The dependencies of the permeability coefficienta on surfactant concentration C at temperatures 23,25,27, and 30 O C have been obtained. The K values strongly depend on C at low concentrations, but they remain constant at higher C. The permeability increases with increasing temperature. The experimental data have been discussed on the basis of the nucleation theory of fluctuational formation of holes in amphiphile bilayers. The results are in favor of an essential contribution of hole-mediated permeability at low surfactant concentrations and higher temperatures.
Nonionic ethoxylated surfactants, including ethoxylated nonylphenols, can be considered as neutral oxygen-containing extraction reagents, the formation of delamination systems with which is possible when salting-out with inorganic salts. In this work, the distribution of halide and thiocyanate acid complexes of thallium (III), iron (III), indium and gallium in the water – ethoxylated nonylphenol (neonol AF 9-12) – ammonium sulfate system at 25°C was investigated. It is established that thallium (III) is quantitatively extracted in the form of tetrahalidetallate-ion with an acidity of more than 0.1 mol/l, extraction of other metals is not quantitative. Among the thiocyanate acid complexes, zinc, cobalt and copper (II) are quantitatively concentrated, which can be used for group concentration of these metals or their extraction-spectrophotometric determination methods
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