selective magnetic removal of pb(ii) from aqueous solution by porphyrin linked-magnetic nanoparticles

the discharge of lead containing effluents into the environment and water bodies is harmful for the human, animals, aquatic flora and fauna. herein, a novel surface engineered magnetic nanoparticle for removing pb2+ ions was studied. after surface modification of the magnetite by 3-amino-propyltriethoxysilane (aptes) magnetic nanoparticles with covalently linked porphyrins were synthesized. two atropisomers of  meso-tetrakis(2-carboxy-4-nonylphenyl) porphyrin (tcnp) were tested to analyze the atropisomeric effect on lead uptake. for characterize the synthesized nanosorbents methods like: transform infrared spectroscopy, x-ray diffraction, transmission electron microscopy and thermo-gravimetric analysis were used. the effects of ph, contact time, sorbent dosage and some co-existing cations were investigated. regeneration of lead adsorbed material could be possible and the modified magnetic nanoparticles exhibited good reusability. the use of such a system can provide fast and efficient removal of the lead ion by using an external magnetic field. the competitive adsorption tests showed good adsorption selectivity for lead ion.