Kinetic and Thermodynamic Studies of Cationic and Anionic Surfactants Adsorption onto Polyethyleneimine-modified Cotton Cloths

Abstract

In order to solve the problem of cationic and anionic surfactants contamination in household wastewater, the adsorption of ionic surfactants from synthetic wastewater by modified cotton cloth was studied. The aim of this work was to investigate the kinetic and thermodynamic adsorption of domiphen bromide (DB) and sodium dodecyl benzene sulfonate (SDBS) on Polyethyleneimine (PEI)-modified cotton cloth. It was found that the SDBS on PEI-treated cotton cloth was higher than that on the untreated cotton cloth 20 % approximately. The results also revealed that DB and SDBS adsorption on both cotton cloth and PEI-modified cotton cloth were Langmuir type and Freundlich type, respectively. The results of zeta potential measurement indicated that the adsorption of surfactants on cotton cloth and PEI-modified cotton cloth lead to decreasing of electrical charge on the surface. The adsorptions of both surfactants were found to follow the pseudo-second order model. Results of the experiments and studies of kinetic and thermodynamic parameters showed that the adsorption processes of DB and SDBS on cotton cloth and PEI-modified cotton cloth were spontaneous and exothermic. The adsorption activation energy was found to be 86.40 kJ mol-1 and 52.13 kJ mol-1for DB and SDBS adsorption on PEI-modified cotton cloth, respectively.