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Cr (VI) toxicity, easily soluble in water, through the food chain in vivo enrichment harmful to human health, is internationally recognized as carcinogenic metal objects, removal of Cr (VI) without delay. Chitosan (Chitosan, CS) because of its wide variety of sources, low cost, easy to cause secondary pollution, etc., in the water treatment Chiang Kai-shek constant attention of researchers, is ideal for heavy metal adsorbent. In this study, the role of coordination between the chitosan and Fe (III), prepared chitosan metal complexes of Fe-CS, instead of Fe (III) with acetic acid, the preparation of cross-linked the chitosan ACOH-CS to Fe-CS and AcOH-CS as adsorbent aqueous solution of Cr (VI) adsorption. And using X-ray photoelectron spectroscopy (XPS) complexes on Fe-CS, adsorption of Cr (VI) Fe-CS complexes desorption Fe-CS complexes were characterized. The results are as follows: (1) fitting t / Qt-t adsorption kinetics curves, linear correlation is very good, in line with the pseudo-second adsorption kinetics equation. The concentration of Cr (Ⅵ) in 50-200mg / L, Fe-CS of the adsorption rate equivalent to the ACOH-CS specific numerical times. Fe-CS on the Cr (VI) adsorption rate constant k2 of the order: k2.50 gt; k2.100 gt; K2-200, Fe-CS maximum of 50 mg / L Cr (VI) adsorption rate, reaching 6.66 min-1.g/mg. (2) 30 ° C, when the Cr () the initial concentration within the range of 0-200 mg / L, the adsorption reached equilibrium, Fe-CS adsorption amount with Cr () increase of the concentration of the initial solution is increased. 30 ° C when the maximum saturation adsorption amount of 145mg / g. (3) Fe-CS having acid resistance, has a good adsorption performance also under low pH conditions, pH 4, Fe-CS for the adsorption amount of 200 mg / L of Cr (VI) is 94.68 mg / g for the same the ACOH-CS adsorption capacity in the pH conditions was 1.65. (4) Cr (VI) solution coexisting ions coexist cation is not on the adsorption inhibition, five common cations Na, Mn2, Ca2, Mg2, Cu2 to the presence of a certain concentration on the Fe-CS adsorption of Cr (VI ) has little effect. (5) XPS chitosan-NH2 group with Fe (III) coordination reaction Fe-CS complexes of iron to trivalent iron; Fe-CS on the adsorption of Cr for reducing the hexavalent price. Fe-CS formation of the adsorption process of Cr (VI), C atoms did not happen coordination role. Speculate that the electrostatic interaction between Fe-CS on the main mechanism for efficient adsorption of an aqueous solution of hexavalent chromium complexes of trivalent iron and the protonated amino group-NH3 Cr2072-in accordance with the corresponding data. The results showed that the chitosan metal complex material Fe-CS is water good adsorbent of Cr (VI) Adsorption.
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