Magnetite nanoparticles with surface modification for removal of methyl violet from aqueous solutions

In this research, the potential of Fe3O4 magnetic nanoparticles (MNPs) for efficient removal of methyl violet as a cationic dye from aqueous solutions was investigated. For this purpose, Fe3O4 MNPs were synthesized via chemical precipitation method. The synthesized MNPs were characterized by XRD and SEM techniques. To remove methyl violet, the surface of the MNPs was modified with sodium dodecyl sulfate (SDS) as an anionic surfactant. Also, the various parameters affecting dye removal were investigated and optimized. The kinetic studies for methyl violet adsorption showed rapid sorption dynamics by a second-order kinetic model, suggesting chemisorption mechanism. Dye adsorption equilibrium data were fitted well to the Langmuir isotherm rather than Freundlich isotherm. The maximum monolayer capacity, (qmax), was calculated from the Langmuir as 416.7 mg g−1. The results show that, SDS-coated magnetic nanoparticles, can be used as a cheap and efficient adsorbent for removal of cationic dyes from aqueous solutions.