The Research About The Flocculability And Preparation Of Starch Graft-Copolymer And Cationic Starch

With the development of modern industrial, more and more waste water have been broughtup, which is harmful to both of the human beings and the environment. However, thetreatment to the waste water is very expensive and poisonous to the human. To develop akind of flocculant which is efficient, low poison and degradable is necessary and urgent.Starch as raw material, widely exists in the nature. It in low price but can make goodperformance in treating waste water especially when it added some new perssad. Starchgraft-copolymer and cationic starch are the examples of them, these two kinds of starchhave been used in many area of industry especially in treating water for it is degradableand kind to the environment. This research on this subject is meaningful.This experimentation chooses corn starch as raw material doing test on thecopolymerization between starch and acrylamide, the cationizational reaction betweenstarch and etherifying agent (CHPTMA). The major context for the study as follows：This study has been researched on the reaction condition of corn starch and acrylamidebeen by way of irradiation. Grafting yield was under the influence of matching ratio ofstarch and acrylamide, concentration of starch and metering of irradiation in the singlefactors’ experiment. The best optimized reaction condition was given by the orthogonal test:matching ratio of starch and acrylamide is1:2, content of starch milk is6%, metering ofirradiation is10kGy. The rate of removal on turbidity can reach as86.33%through the testof kaolin soliquoid when additive amount of the grafted copolymerization is0.7g/L.Then this experimentation adopts semidry method to prepare cationic starch, testing aboutthe dosage of water, sodium hydroxide, etherifying agent, the time and temperature of thereaction. The best optimized reaction condition was given by response surface: additiveamount is26mL,12g,56.43g for water, NaOH and etherifying agent respectively, and thebest reactive temperature and time is83.5℃and3h. In the simulation test, when theadditive amount of cationic starch is0.5g/L, pH equal to7.1, the rate of removal onturbidity can reach75.73%, and the turbidity of the remain is36.4NTU. However, thestabilization of the cationic starch affect by the PH level.In comparing the effect of polyacrylamide in market and the samples of thisexperimentation to remove COD can find both of the two samples can make goodperformance.