Preparation of coated Starch /Fe~0 by using rheological phase reaction method and research on reaction kinetic of Cr(VI) removal in water

The coated nanoscale zero-valent iron( coated Starch /Fe0) was synthesized with starch as coating agent,and by using rheological phase reaction method. The sample was fully characterized by means of XRD,SEM and TEM. The effection of sample dosage,pH values,initial Cr( Ⅵ) concentration and Cu2+concentration on removal rate of Cr( Ⅵ),and the reaction kinetics were investigated. The reaction mechanism was researched about the removal of Cr( Ⅵ) with coated Starch /Fe0. The experimental results indicate that the removal rate of Cr( Ⅵ) was 100% when the sample dosage was 0. 6 g /L,the pH values was 5,and the initial Cr( Ⅵ) concentration was 10 mg /L. Cu2+has promote effect on the removal of Cr( Ⅵ) when the Cu2+and Cr( Ⅵ) coexist in the reaction system. The reaction kinetic follows pseudo-firstorder reaction model.