Abstract:
In order to realize selective adsorption and removal of 2, 4, 6-trichlorophenol (2, 4, 6-TCP) in seawater, a 2, 4, 6-trichlorophenol-imprinted amino-functionalized nano-Fe
3O
4-polymer magnetic composite (nFe
3O
4@MIPNH
2-polymer) was synthesized via ultrasonic assisted suspension polymerization. The composition, structure, morphology and magnetism of nFe
3O
4@MIPNH
2-polymer were characterized by means of Elemental Analysis (EA), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The application for its adsorption and removal properties on 2, 4, 6-TCP pollutant from seawater was investigated. The results show that the nFe
3O
4@MIPNH
2-polymer has an average size of around 800 nm, with the saturation magnetization intensity of 32.6 emu·g
-1. Adsorption isotherm of 2, 4, 6-TCP onto nFe
3O
4@MIPNH
2-polymer accords with Langmuir model, which demonstrate an excellent adsorption capacity with the maximum adsorption capacity at 105.26 mg·g
-1, much higher than that of none-molecular imprinted amino-functionalized nano-Fe
3O
4-polymer magnetic material (nFe
3O
4@NH
2-polymer, with the maximum adsorption capacity at 76.92 mg·g
-1). The isothermal adsorption curve mainly obeys the Langmuir mode. The adsorption thermodynamic studies suggest that the adsorption processes of the 2, 4, 6-TCP by the nFe
3O
4@MIPNH
2-polymer are endothermic, entropy favored, and spontaneous in nature, and the adsorption processes reach the equilibrium within 5 min and the kinetic data are well fitted to the pseudo-second-order model. The activation energy for the 2, 4, 6-TCP removal is 78.0 kJ·mol
-1. There is almost no interference by the coexisting components in seawater for the adsorption of 2, 4, 6-TCP. The nFe
3O
4@MIPNH
2-polymer can be reused at least 5 times after elusion. The 2, 4, 6-TCP in seawater can be selectively and effectively removed by the nFe
3O
4@MIPNH
2-polymer.