Adsorption of Neonol AF 9-9 on the surface of intercalated and thermally expanded graphite

Abstract

A comparative study of the sorption properties of intercalated and thermally expanded graphite with re-spect to the nonionic surfactant neonol AF 9-9, which is an oxyethylatedmonoalkyl phenol, was carried out using the tensiometer method. It was experimentally established that the adsorption process on both materials is described by the Freundlich isotherm. This indicates the physical nature of sorption and the energy heterogeneity of the surface of inter-calated and thermally expanded graphite. Since heat treatment leads to a significant change in the structure of the mate-rial ‒ the formation of a developed system of micropores and an increase in the specific surface ‒ thermally expanded graphite demonstrates a 4-fold greater adsorption capacity compared to the intercalated form. The results obtained are of great importance for the development of effective sorption methods for cleaning industrial wastewater from toxic surfactants.Keywords: