Abstract

new polystyrene-divinylbenzene chelating resin containing 4,5-dihydroxy- naphthalene-2,7- disulfonic acid (chromotropic acid : CTA) as functional group has been synthesized and characterized. The sorption and desorption properties of this chelating resin for Cr(Ⅲ) ion and Cr(Ⅵ) ion including nine metal bloodstain. As a results, FOB test kit could be effectively applied to identification of human blood at chelating resin was stable in acidic and alkaline solution. The Cr(Ⅵ) ion is selectively separated from Cr (Ⅲ) ion at pH 2 and the maximum sorption capacity of Cr(Ⅵ) ion is 1.2 mmol/g. In the presence of anions such as F-, SO42-, CN-, CH3COO- and NO3-, the sorption of Cr(Ⅵ) ion was reduced but anions such as PO43- and Cl- revealed no interference effect. The elution order of metal ions obtained from breakthrough capacity and overall capacity at pH 2 was Cr(Ⅵ)＞Sn(Ⅱ)＞Fe(Ⅲ)＞Cu(Ⅱ)＞Cd(Ⅱ)≃Pb(Ⅱ)≃Cr(Ⅲ)≃Mn(Ⅱ)≃Ni(Ⅱ)≃Al(Ⅲ). Desorption characteristics for Cr(Ⅵ) ion was investigated with desorption agents such as HNO3, HCl, and H2SO4. It was found that the ion showed high desorption efficiency with 3 M HCl. As the result, the chelating resin, XAD-16-CTA was successfully applied to separation and preconcentration of Cr (Ⅵ) ion from several metal ions in metal finishing works.