Metal uptake system with surfactant layer on silica gel - Adsorption and desorption behavior in preparation steps

PAN (1-(2-pyridylazo)-2-naphthol) was immobilized into admicelles of nonionic surfactant (Triton X-100) on silica gel. In this work, the interesting interfacial phenomena in preparation of a metal uptake system using the admicelles were investigated. It was clear that adsorption of micelles of Triton X-100 was significantly affected by both kind and amount of alcohol. The adsorption amount of Triton X-100 micelles increased with the following order: methanol > ethanol > 2-propanol > 1-propanol > tert-butanol. The order was well correlated by the octanol-water partition coefficients of these alcohols. The stability of the system was examined under various environmental factors for its practical use. The system was very stable under normal conditions, e.g. temperature, 298-318 K; time course, 0-52 hours; pH, 2.5-12.0. Although the system was not stable under a severe condition of pH (<2.5 and >12.0).