Synthesis of oxidation corn starch with composite oxidation

Corn starch was used as material in acid conditions to prepare oxidized starch by wet technology where hydrogen peroxide and potassium sulfate was used as oxidant and Fe~(2+) as catalyst. To starch milk concentration,composite oxidant proportion,composite oxidant mass fraction(the percentage of the dry starch ),catalyst mass fraction(the percentage of the dry starch ),reaction temperature,reaction time factors as a variable,with the content of carboxyl as oxidation of starch for measure oxidation degree,the optimum process conditions of oxidation starch were determined by the single factor experiments starch and the orthogonal experiment as follows:the starch milk concentration was 35%,composite oxidant mass fraction was 8%,composite oxidant proportion[m(H_2O_2 ):m (K_2S_2O_8)]was 4:1,the system pH value was 4.00,catalyst mass fraction was 0.3%,the reaction temperature was 50℃,the reaction time was 1.5 h.Under above conditions,oxygenation corn starch could be obtained with oxidation degree of 0.118%.