Surfactants modified egg shells for removal of methyl violet from aqueous solutions

摘要

Two surfactant-modified egg shells were prepared and characterized by XRD patterns, FT-TR spectra and scanning electron microscopy (SEM). SEM images showed surfactants-modified egg shells were with more clear porous structures. The methyl violet (MV) removal using egg shell and surfactant-modified egg shells were compared. The MV removal of surfactant-modified egg shells showed better, and that of potassium perfluorooctanesulfonate (PFOS)-modified egg shell is better than that of Sodium octanesulfonate (SOS)-modified one. It can be concluded that the MV removal of surfacant modified egg shell is better when surfactant is more hydrophobic. The adsorption of egg shell fits the pseudo-first-order kinetic model and surfactant modified egg shells fit pseudo-second-order kinetic model. All adsorptions fit Freundlich isotherm. Dubinin-Radushkevich (D-R) isotherm showed the adsorption mainly was a physical adsorption process.