Impact of linker molecules on adsolubilization of organic compounds by using hydrophobic silica modified with EO/PO triblock copolymers

Abstract

For the past decade, the use of an adsolubilization process to adsorb organic compounds has drawn increasing attention. The process has been found to be useful in applications for the removal of organic compounds from waste water by using solid particles modified with various types of surfactants. Recently, Ethylene Oxide/Propylene Oxide triblock copolymers, a nonionic macromolecular surfactants, which have a good detergency property, low toxicity and low desorption, have been used to adsorb onto various solid surfaces such as hydrophobic silica in order to study the adsolubilization of various organic compounds. The adsorption of EO/PO triblock copolymers (P123, L64, 25R4) onto hydrophobic silica by using both a lipophilic linker (tetradecanol) and a combined linker (sodium dodecyl benzene sulfonate/dodecanol), and the adsolubilization behavior of the modified hydrophobic silica for model organic compounds (phenol, 2-naphthol, and naphthalene) were studied. The results showed that by having the linker molecules in the system, the adsorption of almost all the triblock copolymers, used in this study, onto the hydrophobic silica surface increased. In the adsolubilization study, the results showed that the modified hydrophobic silica in the systems with linker molecules showed higher adsolubilized amounts of the model aromatic organic molecules than the systems without linker molecules.