【摘要】 自制的ACS是一种带有支链的改性天然高分子物质,其羧基取代度为0.57,阳离子取代度为0.02。吸附动力学研究表明,ACS对Ca2+的吸附速率快,两者之间有较强的吸附作用力,且吸附动力学曲线只出现一个"平台"。等温吸附研究表明,ACS对Ca2+的吸附符合Langmuir模式和Freundlich模式,为单分子化学吸附。吸附量随pH值的升高而增加,当pH值>6.5,并基本保持不变时,在实验浓度范围内,吸附量随着Ca2+初始浓度的增加而升高,当Ca2+加入量为3.93 mmol/L,ACS用量为2.0 g/L,pH值为6.5±0.1时,25℃、45℃、65℃的平衡吸附量分别为0.687、0.743和0.826 mmol/g;当Ca2+初始浓度为0.983 mmol/L时,ACS的用量为2.0 g/L达到最佳效果,用量继续增加,吸附量反而下降。更多还原

【Abstract】 The ACS,a modified natural high molecular polymer having 0.57 mol/mol DS of carboxyl groups and 0.02 mol/mol DS of cationic,was used as the calcium ions adsorbent that can adsorb and transfer calcium ions from aqueous solution to fibers.The study result of adsorbing dynamic indicated that the adsorption rate of calcium ions onto ACS was fast,and the adsorption equilibrium time was about 90 min.The kinetic curve had one "plateau",which revealed that there was one single molecular adsorption mechanism.The equilibrium data were found according to the Langmuir and Freundlich adsorption isotherms.The adsorption capacity increased with increasing pH and became almost constant when pH above 6.5.When the initial concentration of calcium ion was 3.93 mmol/L,the equilibrium adsorption capacities were 0.687 mmol/g,0.743 mmol/g,0.826 mmol/g at 25℃,45℃,65℃ respectively.When the initial concentration of calcium ion was 0.983 mmol/L,the adsorption capacity reached the maximum at the dose 2.0 g/L of ACS.更多还原