【摘要】 采用搅拌球磨机对木薯淀粉进行机械活化,以不同活化时间的木薯淀粉为原料,CuSO4为催化剂,H2O2为氧化剂干法制备氧化淀粉,并以钙离子配位能力为评价指标,分别考察羧基含量、pH值、温度、钙离子浓度、配合时间等因素对木薯氧化淀粉软化硬水能力的影响。实验结果表明,机械活化对木薯氧化淀粉软化硬水的能力有显著的影响。由活化60 min的木薯淀粉制得的氧化淀粉当羧基含量为0.49%及0.84%时,在体系pH 10、温度30°C、钙离子浓度4 mmol/L、配合时间20 min的条件下钙离子的配合量分别为106.7 mg/g及136.70 mg/g,而在相同条件下,由原木薯淀粉制得的氧化淀粉当羧基含量为0.49%时,钙离子的配合量仅为48.0 mg/g。更多还原

【Abstract】 Cassava starch was mechanically activated by a stirring-type ball mill.Using H₂O₂ as oxidant and CuSO₄ as catalyst,the oxidized starch was prepared by dry method from cassava starch of different activated times.The effect of carboxyl content of oxidized starch,pH,temperature,concentration of calcium ion,and complexing time on the capability of softening hard water of cassava oxidized starch was investigated by using calcium-complexing capability as the evaluating parameter.The results indicated that mechanical activation considerably influenced the capability of softening hard water of cassava oxdized starch.When the pH value of the system was 10,the temperature was 30（°C）,the concentration of calcium ion was 4 mmol/L,and the complexing time was 20 min,the extent of calcium-complexing of the oxidized starch with activation time of 60 min was 106.7 mg/g and 136.70 mg/g when the carboxyl content of the oxidized starch was 0.49% and 0.84%.It was only 48.0 mg/g for the oxidized starch from native starch when the carboxyl content of the oxidized starch was 0.49%.更多还原