Zefei Zhang, Cholhwan Kim, Carlos Fernandez, Manickam Minakshi Sundaram, Thippeswamy Ramakrishnappa, Yuhong Wang, Linshan Wang, Ting Sun, Xiaomin Hu
August 17, 2016
We report the preparation and employability of carbon-coated Fe 3 O 4 (Fe 3 O 4 /C) microspheres functionalized with chloroacetic acid (CAA) for the removal of methylene blue (MB) in aqueous solution. The prepared magnetic microspheres (Fe 3 O 4 /C-CAA) were characterized by the following techniques: X-ray diffraction, transmission electron microscopy, Fourier-transform infrared spectrometer, vibrating sample magnetometry, and Brunauer-Emmett-Teller. The characterization results showed that Fe 3 O 4 /C microspheres were modified by CAA without any phase change. Fe 3 O 4 /C-CAA microspheres have higher adsorption capacity for MB compared to Fe 3 O 4 /C microspheres. The Langmuir, Freundlich, and Temkin adsorption models were applied to describe the equilibrium isotherms, and the Langmuir adsorption model fitted well with the equilibrium data. The pseudo-first-order and pseudo-second-order kinetic models were used to describe the kinetics data. However, the pseudo-second-order kinetic model fitted better with the adsorption kinetics data.