High Substitution Properties Of Cationic Starch

1. Research on Starch glycerine ether:The synthesis methods of Starch glycerine ether have been studied, and tentatively tested its performance as oil drilling fluid loss additive. Than the surface of the cationic starch in structure and an extra hydroxy, it will be increased Starch glycerine ether of water soluble. Starch glycerine ether is prepared from corn starch and 3-chloro-1,2-propanediol under alkaline conditions. In the synthesis reaction the content of water and sodium hydroxide (catalyst) cannot be too large, the reaction temperature should not exceed 70℃, and the reaction time no more than 5h. It's diaphaneity, acidoresistance, high temperature stability are all improved than original starch. The effect in fresh water drilling fluid, sea-water drilling fluid and saturated brine drilling water of Starch glycerine ether is different.2. Research on cationic starch CS:The cationic starch (CS) with high degree of substitution, of which the oil-displacement capacity was investigated, was synthesized with the dry method through the reaction of maize starch with 2,3-epoxypropyl trimethyl ammonium (ETA) chloride, catalyzed by sodium hydroxide. It was indicated that when m (NaOH)/m (starch)=0.02 and n (ETA)/n (starch)=0.33, the degree of substitution of CS and the conversion rate of the reaction were respectively 0.30 and 90% after the reactants were heated at 55℃for one hour and dried in a vacuum for four hours. In the stimulation experiment of oil displacement with the salinity of fluid of 40 g/L,5 g/L CS solution could improve the oil recovery by 24.1% and 10 g/L CS by 36.7% with the occurrence of two maximums of pressure,0.044 Mpa and 0.041 MPa. The oil-displacement capacity of CS solutions was stronger than that of 3 g/L partially hydrolyzed polyacrylamide (PHPA) solution. Though the concentrations of CS solutions were greater than that of PHPA solution, the cost of the former was less than that of the latter and CS solution wouldn't pollute the environment. 3. A cationic starch with high degree of substitution developed in laboratory was used as the flocculant to treat the white water from paper mill. The effects of the dosage of the said cationic starch, the pH value of the waste water and the time of flocculation on the result of the flocculation were approached through experiments. With the optimum conditions for the treatment of the white water from paper mill using the said cationic starch so determined that the dosage of the said cationic starch should be 200 mg/L without adjusting the pH value,which will give a flocculating time of 24 hours.