| In recent years, heavy metal ion pollution problem has already become one of the biggest water pollution problems.There are many methods to remove heavy metal ions, including chemical precipitation, ion exchange, adsorption, membrane filtration, etc.Adsorption,which are widely applied is a method of all countries. In recent years, many scholars have dedicated to seeking out an economic and practical adsorbent.After many scholars research chelating resin for many years, the resin has repeatedly present manifold which can be used to eliminate trace heavy metal ions in the water. Almost all natural and synthetic polymer can be used as its maternal molecules, such as:polystyrene ene acids, polyvinyl alcohol classes, crosslinked polystyrene class starch, such as cellulose classes and chitin. Monomer styrene raw material is convenient, inexpensive, can be made by petrochemical large producing, and can easily access different nature of the groups, all the properties make it has different function and suitable for different purposes, etc.In this article, chlorine methylation polystyrene balls (PSC) is used as the main body, Preparation of three new disablement chelating resin espectively with ethylenediamine tetraacetate (EDTA), divinyl 3- amine (DETA) and 3- ethylene 4- amine (TETA).In this paper, research for the purpose of removing the heavy metal ions in the water and research for the adsorption properties of different synthesis of several amino group of polystyrene to adsorb heavy metal ions. Spectrophotometry was used to determine the heavy metal elements.The best adsorption conditions for all the 3 kind of resin to adsorb different kind of metal ions was:the best adsorption time was 2h,pH 5-6,the biggest adsorption quantity of PS-EDTA resin to adsorb the three metal ions was respectively Cu(II),42.1mg/g, Pb(â…¡),32.1mg/g, Zn(â…¡), 83.17mg/g. For PS-DETA, the most adsorption quantity was respectively:Zn(â…¡),89.1mg/g and Cd(â…¡),63.8mg/g.For PS-TETA was respectively:Zn(â…¡),69.9mg/g and Cd(â…¡),78.3mg/g. The desorption effect of HCl and HN03 for the several ions is good,can achieve almost 100%.The dynamic adsorption of heavy metals of the PS chelating resins with nitrogen coordination was studied. (1)At different initial concentration conditions, the adsorption of PS-EDTA for Cu(â…¡) and Pb(â…¡) was 49.8 mg/g and 48.7 mg/g at 50mg/L,87.4mg/g and 91.2 mg/g at 100mg/L. The maximum dynamic adsorption of Zn(â…¡) was 78.2mg/g and 169.1mg/g.(2) The most dynamic adsorption of PS-DETA for Cd(â…¡) and Zn(â…¡) was 189.8 mg/g and 156.4 mg/g at 200mg/L,377.4mg/g and 291.2 mg/g at 500mg/L,respectively.(3) The most dynamic adsorption of PS-TETA for Cd(â…¡) and Zn(â…¡) was 179.4 mg/g and 151.7 mg/g at 200mg/L,368.2 mg/g and 287.1 mg/g at 500mg/L,respectively.At the range of the concentration, the isotherm of adsorption of amino resin to heavy metals was fit with Langmuir and Freundlich model well,both of their correlation coefficient are bigger than 0.98. Both of them can describe the behavior of the adsorption of amino resin well. Through the amino resin adsorption of heavy metal ions in water, the dynamics research shows that:the amino resin for heavy metal ions adsorption process fit pseudo-second-order kinetic model more appropriately. Preliminary study was discussed for heavy metal ions adsorption on the resin, the mechanism of function group of the amino resin and heavy metal ions formation caused by the coordination mu. PS amino resin can be recycled, it laid the foundation to reduce the processing cost.
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