Enhanced adsorption of pharmaceuticals onto core-brush shaped aromatic rings-functionalized chitosan magnetic composite particles: Effects of structural characteristics of both pharmaceuticals and brushes+
Zhou, X (Zhou, Xia)[ 1 ] ; Dong, C (Dong, Chang)[ 1 ] ; Yang, Z (Yang, Zhen)[ 1 ]*（杨朕）; Tian, ZQ (Tian, Ziqi)[ 4 ] ; Lu, LS (Lu, Lishi)[ 1 ] ; Yang, WB (Yang, Weiben)[ 1 ]*（杨维本）; Wang, YP (Wang, Yuping)[ 1 ] ; Zhang, LM (Zhang, Limin)[ 1 ] ; Li, AM (Li, Aimin)[ 2 ] ; Chen, JQ (Chen, Jianqiang)[ 3 ]*
[ 1 ] Nanjing Normal Univ, Sch Environm, Sch Chem & Mat Sci, Jiangsu Prov Key Lab Mat Cycling & Pollut Control, Nanjing 210046, Jiangsu, Peoples R China
[ 2 ] Nanjing Univ, Sch Environm, State Key Lab Pollut Control & Resource Reuse, Nanjing 210023, Jiangsu, Peoples R China
[ 3 ] Nanjing Forestry Univ, Coll Biol & Environm, Nanjing 210037, Jiangsu, Peoples R China
[ 4 ] Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA
JOURNAL OF CLEANER PRODUCTION,201801,172,1025-1034
Core-brushes shaped chitosan/Fe3O4 composite particles (CS-MCPs) have been demonstrated applicable in the removal of pharmaceuticals due to the large amounts of functional groups on branches and heightened approachability of flexible branches to contaminants. To further enhance adsorption capacity (Q(e)) and pH-resistance, novel representative core-brushes shaped aromatic rings-functionalized CS-MCPs were used for adsorption of typical pharmaceuticals (norfloxacin, tylosin and diclofenac sodium (DCF)). For norfloxacin and tylosin, modified CS-MCP with polyanions (poly(sodium p-styrenesulfonate)) branches exhibited high Q(e) (165 mg/g and 134 mg/g, respectively); whereas for DCF, modified CS-MCP with polycations (poly(p-vinylbenzyl trimethylammonium chloride)) branches is favored (151 mg/g). Due to existence of phenyl groups on branches, Q(e), remained high levels in a wide pH range, proving improved pH-resistance. Considerable resistance against coexisting pharmaceuticals and inorganic ions, as well as reusability, of the adsorbents, were found. Physico-chemical analyses, instrumental characterizations and theoretical calculations demonstrated that electrostatic attraction and pi-electron-containing interactions contributed to adsorption: charged ends of contaminants were fixed to oppositely charged part of branches; whereas other fragments of pharmaceutical molecules bound with pi-electrons of phenyls on branches. The novel core-brush shaped biopolymer-based MCP5 showed potential in water treatment and guidance for designing the brush characteristics was provided according to pharmaceutical characteristics.