Synthesis and characterization of magnetic chitosan microspheres as coking wastewater adsorbents

• DOI: 10.1016/j.dwt.2025.101020
• Publication Date: 2025-01-26T17:33:55Z
• Authors: Yunlong Zhao; Hao Peng; Lei Zhang; Wanwan Fu; Man Zhang; Zhishan Chen; Longfei Li; Yutao Chen
• Keywords: Characterization

As a new type of polymer functional material, magnetic chitosan has been widely used in wastewater treatment. In this study, magnetic chitosan microspheres (MCMs) were prepared by reversed-phase microemulsion cross-linking technology, and the adsorption capacity of MCMs to organic pollutants with high chemical oxygen demand (COD) in coking wastewater was studied. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS), brunauer - emmett - teller (BET), vibrating sample magnetometer (VSM) were characterized. The effects of Fe3O4 magnetic nanoparticles (MNPs), pH and the amount of adsorbent on the adsorption properties of MCMs were investigated. The following conclusions are obtained: the MCMs prepared in this study are successfully encapsulated, and the MCMs have good magnetic properties; Meanwhile, the removal performance of COD is higher. When the addition amount of Fe3O4 is 10 % of the mass fraction of chitosan, the maximum adsorption amount of COD by MCMs can reach 261.82 mg/g under the conditions of pH 7.5, reaction temperature 298 K and adsorption time 42 h. The adsorption kinetics can be described by a quasi-second-order kinetic model. In addition, after 4 times of adsorption-desorption processes, the adsorbent still has more than 40 % COD adsorption, and has good adsorption performance. In general, because of the high adsorption efficiency, strong regeneration and excellent magnetic separation performance, MCMs have practical application potential in sewage treatment, biomedicine and other fields.