Efficient removal of anionic dyes from aqueous media using newly in situ synthesized triazine-based nitrogen-rich network-modified magnetic nanoparticles

In this research, a triazine-based polymeric network surface-modified magnetic nanoparticles (TPN/MNPs) were synthesized for the adsorption of anionic compounds. To obtain TPN/MNPs, melamine-terephthaldehyde polymeric network was synthesized in the presence of magnetic nanoparticles. After characterization by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and transmission electron microscopy (TEM), the adsorption behaviors of methyl orange (MO) as model anionic dye on TPN/MNPs were investigated. Obtained results showed MO removal efficiency has not been influenced by pH (5-9) and high salt concentration (up to 10% w/v) of the solution. The adsorption isotherm was described by Langmuir model. The results indicated that TPN/MNPs adsorbed MO effectively with a large capacity of 80.6 mg g(-1). The adsorption reached the equilibrium within 10 min and the kinetics followed pseudo-second-order model. The magnetic separation after adsorption was easily achieved, and TPN/MNPs could be quantitatively regenerated by washing with 1.0 mL of the mixture of methanol/0.1 mol L-1 HCl (50:50, v/v%) solution. The results confirmed that TPN/MNPs have the potential superiority in removal of MO from aqueous solution.