葫芦脲[6]接枝壳聚糖的制备及其对偶氮染料的吸附研究

Fabrication of cucurbit[6] uril-grafted chitosan and its adsorption of azo dye from aqueous solution

制备葫芦脲[6]接枝壳聚糖(CB[6]-CS)吸附剂,分别获得3种不同接枝率的CB[6]-CS,并对其结构进行表征。将合成的3种吸附剂CB[6]-CS用于对酸性铬兰K染料进行吸附研究,分别考察了温度、pH值、染料浓度、吸附时间及CB[6]含量对吸附性能的影响。结果表明:CB[6]含量较高时,CB[6]-CS对酸性铬兰K有较高的去除率,并且,CB[6]-CS对酸性铬兰K的吸附作用受溶液的温度和pH影响较大,适宜的吸附条件为25℃,pH大于6.5。通过吸附等温线研究,可知,CB[6]-CS对酸性铬兰K的吸附规律更符合Freundlich吸附等温式;吸附动力学采用了准一级速率方程和准二级速率方程来描述,结果表明吸附动力学符合准二级速率方程。

Three cucurbit[6]uril grafted chitosan （CB[6]-CS） were prepared. The composition of CB[-6]-CS absorb- ents were characterized by FT-IR. The CB[6]-CS was further used to absorb acid chrome blue. The content of CB[6] in CB [6]-CS played an important role for the adsorption of acid chrome blue. The adsorption capacity increased with increasing CB[6] content for CB[6]-CS. Meanwhile, the acid chrome blue adsorption was highly dependent on initial concentration of acid chrome blue,temperature and initial solution pH value. High pH value was favorable for the adsorption of acid chrome blue on CB[6]-CS. Utilizing pseudo-second-order equation provided the best correlation for the experimental data. Adsorp- tion isotherm study suggested that acid chrome blue adsorption on CB[6]-CS best followed Freundlich isotherm model. The excellent adsorption capacity for acid chrome blue and relatively low cost made CB[6]-CS very useful for application in wastewater treatment.