Study On Preparation Of Magnetic Polymer Adsorbent And Its Adsorption Of Cu(Ⅱ)

Chelating resin can selectively and efficiently adsorb heavy metal ions in aqueoussolutions by the formation of coordination bonds with metal ions to form a multi-ringcomplex. It is a kind of crosslinked polymer material with special ligand functionalgroups. Dithiocarbamates have plurality of hetero atoms, such as nitrogen, sulfur,being easy to form stable complexes with a variety of heavy metals. Because of thehigh adsorption capacity and rapid separation characteristics, chelating resin withdithiocarbamate groups can be used to the adsorption of heavy metal ions.In this thesis, magnetic polymer microspheres were prepared by miniemulsionpolymerization, with styrene and glycidyl methacrylate (GMA) being used asmonomers and Fe3O4particles prepared by chemical coprecipitation method beingused as magnetic cores. Ethylenediamine dithiocarbamate, synthesized from carbondisulfide, ethylenediamine and sodium hydroxide, was used to modify magneticpolymer microspheres to obtain novel magnetic adsorbent. Adsorption properties ofthe adsorbent for the removal of heavy metal ions were studied.The results show that Fe3O4particles by the preparation of coprecipitationmethod have the typical inverse spinel crystal pattern, displaying superparamagneticproperty and high saturation magnetization of41.62emu/g. The magnetic adsorbenthas spherical morphology and its saturation magnetization is1.26emu/g. The size ofmagnetic microspheres is affected by the content of GMA, showing a trend ofdecrease with increasing the GMA content.Magnetic adsorbents obtained by different means show significant differentadsorption capacities for the removal of Cu2+. The optimum adsorption condition foradsorbent is pH=4.5in solution and the removal efficiency is more than90%. Theadsorption capacity increases with time and the initial concentration of Cu2+. In thepresent work, the increase of functional group is benefit for the adsorption effect, butthere is no obvious difference. The isotherm study shows that the adsorption dataagree to Langmuir and Freundlich isotherm equations, indicating that the adsorption process is monolayer adsorption; the Lagergren pseudo-second-order kinetic datashows that the adsorption rate increases with the initial ion concentration, indicatingthat chemisorption occurs between adsorbent and Cu2+in the adsorption process.