Adsorption of pharmaceuticals on chitosan-based magnetic composite particles with core-brush topology

作者：Zhang, Shaopeng; Dong, Yayi; Yang, Zhen^*; Yang, Weiben^*; Wu, Jiaqing; Dong, Chang

来源：Chemical Engineering Journal, 2016, 304: 325-334.

DOI：10.1016/j.cej.2016.06.087

• Magnetic composite adsorbents
• Core-brush topology
• Pharmaceuticals
• Diclofenac sodium
• Tetracycline
• Adsorption mechanism

A series of magnetic composite adsorbents with core-brush topology were prepared through grafting co-polymerization on the surface of chitosaniFe(3)O(4) composite particles (CS-MCP), and then applied for the removal of two pharmaceuticals (diclofenac sodium (DCF) and tetracycline hydrochloride) from water. Adsorption performance evaluation, including adsorption capacities from single- and binary solute solutions at different pHs, influences of coexisting salts, desorption and reusability, demonstrated CD-MCP with polycationic brushes was a cost-effective adsorbent for DCF removal: Compared to CS-MCP, all the modified MCP5 exhibited higher removal efficiencies, due to the enhanced surface areas resulting from core -brush topology; Among the modified MCP5 with different surface charges, CD -MCP displayed the highest adsorption capacities, attributed to the electrostatic attraction between the positively charged brushes and the anionic contaminant's species. Adsorption mechanism was investigated from both the macroscopic (thermodynamics and kinetics) and microscopic (changes of solution pH and spectral analyses of the adsorbent after adsorption) viewpoints: Charge attraction was the intrinsic driving force; A monolayer coverage of pharmaceuticals were adsorbed onto the brushes of CD-MCP; OH exerted competitive adsorption effect; After adsorption, the originally extended polycationic brushes turned collapsed. The current study provided a strategy for the design of adsorbents from both topological and chemical structures.

• 出版日期2016-11-15
• 单位南京师范大学