Xie Yan-Hua, Li Shi-Yu, Wang Fei, Liu Guang-Li
School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China.
Huan Jing Ke Xue. 2009 Sep 15;30(9):2580-5.
Cross-linked chitosan gel beads were used to adsorb perchlorate (ClO4-) from water. Batch experiments were conducted to investigate the effects of temperature, pH, and initial ClO4- concentration, adsorption isotherms and kinetics, and regeneration ability. The adsorption process of ClO4- on chitosan is exothermic reaction. The adsorption capacity varies from 37.98 mg x g(-2) to 34.39 mg x g(-1) with the pH changes from 3.0 to 6.0 when the initial ClO4- concentration is 100 mg x g(-1). The adsorption capacity increases with the initial ClO4- concentration increase, and the maximum reaches up to 128.78 mg x g(-1) at the initial ClO4- concentration of 400 mg x L(-1). The equilibrium data fit Langmuir and Freundlich isothermal models well. In addition, the adsorption process can be explained by the pesudo-second-order kinetic model, and the chemisorption is the limit step for adsorption velocity. Finally, the adsorbent can be easily refreshed by pH 12.8 NaOH and repeatedly used for 10 cycles without obviously destruction.
交联壳聚糖凝胶珠用于从水中吸附高氯酸盐（ClO4-）。进行了批量实验，以研究温度、pH值和初始ClO4-浓度、吸附等温线和动力学以及再生能力的影响。ClO4-在壳聚糖上的吸附过程是放热反应。当初始ClO4-浓度为100 mg x g(-1)时，随着pH值从3.0变化到6.0，吸附容量从37.98 mg x g(-2)变化到34.39 mg x g(-1)。吸附容量随着初始ClO4-浓度的增加而增加，在初始ClO4-浓度为400 mg x L(-1)时，最大值达到128.78 mg x g(-1)。平衡数据很好地符合朗缪尔和弗伦德利希等温模型。此外，吸附过程可以用伪二级动力学模型来解释，化学吸附是吸附速度的限制步骤。最后，吸附剂可以用pH 12.8的NaOH轻松再生，并重复使用10个循环而无明显破坏。
