Preparation of Modified Chitosan and Application in Treating Tanning Wastewater

In this paper,the chitosan was modified under the protection of nitrogen,based on ammonium persulfate and sodium bisulfite as the initiator,and acrylamide as the graft material.As a result,the grafted acrylamide copolymer(CAM) was prepared and used to treat tanning wastewater.And the optimal dosage of CAM in the treatment of chromium-containing wastewater,the suitable stirring time and speed,and the optimum pH value were determined.Results showed that the optimal dosage of CAM should be 2 mg·L-1 in the flocculation treatment of the wastewater,and when pH value was 7.8,the stirring speed was 200 r·min-1,the stirring time was 3 minutes,and the settlement time was 4 hours,the best flocculation result was got and the removal rate of Cr(Ⅲ)was 94%.