Preparation of Anion Exchangers from Wheat Straw and Removal of NO_3~- by Modified Wheat Straw

Wheat straw was modified into anion exchanger for the removal of nitrate by using epichlorohydrin as etherifying agent and dimethylamine as aminating agent.Catalysis time is the main factor that affects the efficiency of modification,while activation time,reaction time,and the amounts of wheat straw,catalyzer,and dimethylamine are the minor factors.The best reaction parameters are wheat straw 2 g,epichlorohydrin 20 mL,dimethylformamide 25 mL,catalyzer 15 mL,dimethylamine 30 mL,activation time 1 h,catalysis time 1 h and reaction time 3 h.The nitrate removal rate was 78.13% if the product was prepared under this condition.