The Preparation Of Magnetic Polymerized Microsphers And The Adsorption Property Study On Cadmium(?)

The porous polystyrene microspheres,magnetic polystyrene microspheres and magnetic epoxy crosslinked microspheres were prepared through suspension polymerization in a stainless steel reactor.The functional groups were produced on the surface of magnetic microspheres viasulfonation and hydrolysis reaction.The adsorption properties of magnetic microspheres on Cd2+were investigated.During the preparation process of polystyrene microspheres,the effects of the amount and ratio of dispersant,crosslinker and orogenic agent on particle size distribution and pore structure were investigated.The obtained microspheres showed good monodispersity when the dispersant PVA/PVP mass ratio was 1:1,the crosslinker DVB/TAIC ratio was 2:1,and the orogenic agent toluene/n-heptane was 1:1?volume ratio?.Within a certain range,the increase of crosslinking agent led to a reduction in pore size and an increase in the specific surface area of the microspheres while the larger proportion of toluene caused smaller pore size and specific surface area.Magnetic cation exchange polystyrene resin?MCER?was prepared by incorporation of oleic acid-modified magnetite particles into polymerization reaction of styrene.The saturation magnetization of MCER is 12.07 emu/g.The results from adsorption experiments showed that when the temperature was 303 K and the concentration of Cd2+ was 100 mg/L,the equilibrium adsorption capacity?Qe?of MCER reached 43.19 mg/g,and the adsorption on Cd2+conformed to pseudo-second-order kinetic model and Freundlich model.The epoxy group-based magnetic microspheres MPMDG1 and MPMDG2 were prepared by polymerization of MMA and GMA,and followed by alkaline hydrolysis and acid hydrolysis.The saturation magnetization for MPMDG1 and MPMDG2 was 17.26 emu/g and 6.29 emu/g,respectively.The Qe of MPMDG2 was higher than that of MPMDG1.When the temperature was 303 K and the concentration of Cd2+ was 100 mg/L,the Qe of MPMDG2 reached 44.66 mg/g,and the adsorption on Cd²⁺conformed to the pseudo-second-order kinetic model and Freundlich model.