Magnetic beads embedded in poly (sodium-p-styrenesulfonate) and ZIF-67: Removal of nitrophenol from water.

Abstract Owing to the diverse structures and unique characteristics of MOFs, the combination of magnetic particles with porous MOFs is an attractive way for rapid and efficient extraction of organic pollutions from water. In this work, the magnetic porous composites, Fe 3 O 4 -PSS@ZIF-67 (PSS, poly (sodium-p-styrenesulfonate)), were prepared. The obtained composites exhibit core-shell structure, for which the spherical Fe 3 O 4 particles as core are embedded in ZIF-67 shell. The existence of SO 3 − anions on poly (sodium-p-styrenesulfonate) is the key factor for the uniform coating of ZIF-67 on Fe 3 O 4 particles. Poly (sodium-p-styrenesulfonate) providing enough chelating sites (-SO 3 −) for Co2+ which could further coordinate with 2-methylimidazole to form ZIF-67. This work further studied the adsorption property of 2-nitroresorcinol in aqueous solution, using Fe 3 O 4 -PSS@ZIF-67 as adsorbents. The equilibrium adsorption capacity for 2-nitroresorcinol is up to 52.50 mg g−1. The adsorption kinetics were investigated. The mechanism could be attributed to the electrostatic interaction between 2-nitroresorcinol and Fe 3 O 4 -PSS@ZIF-67 composites. Graphical abstract A new magnetic porous composites (Fe 3 O 4 -PSS@ZIF-67) was prepared, for which poly (sodium-p-styrenesulfonate) links the spherical Fe 3 O 4 core and ZIF-67 coating. The composites perform well on nitrophenol from aqueous solution via magnetic separation operation, mainly owing to the porosity of ZIF-67 and the electrostatic interaction between nitrophenol and composites. The combination of magnetic separation with MOFs is attractive way for efficient removal of nitrophenols from waste water. fx1 [ABSTRACT FROM AUTHOR]