Reusable cysteine-ferrite-based magnetic nanopowders for removal of lead ions from water

Magnetic nanopowders were developed by functionalization of bimagnetic core@shell nanoparticles with cysteine (CoFe2O4@ɣ-Fe2O3@Cys), which present a core high saturation magnetization (CoFe2O4) combined shell long-term chemical stability (ɣ-Fe2O3) and sorptive L-cysteine layer. Samples two different mean sizes elaborated characterized XRD, TEM, FTIR, SER, zetametry SQUID magnetometry. The adsorption Pb(II) the magnetic was investigated as function pH, time, pollutant concentration. Langmuir model fitted well data indicating monolayer adsorption, maximum capacity 1.2 mg/g found for pH 5. kinetic correlated to pseudo-second-order best equilibrium time 120 min. mechanism mainly involves electrostatic interactions in 5-7 hard–soft-acid–base low pH. Moreover, recovered reused readsorption experiments keeping good removal efficiency.