不同吸附材料对水中高氯酸盐的去除效果比较研究

首先通过高氯酸盐的吸附平衡实验,比较8种不同吸附材料的吸附能力。实验结果表明:对高氯酸盐吸附,Langmuir模型拟合效果要优于Freundlich模型,吸附类型主要为单层吸附。对不同吸附材料的高氯酸盐吸附自由能计算也得出,高氯酸盐的吸附主要为化学吸附。8种材料吸附能力由大到小依次为:阴离子交换树脂>木质活性炭>椰壳活性炭>煤质活性炭>壳聚糖>沸石>膨润土>颗粒氢氧化铁。研究中还对高氯酸盐的吸附动力学进行探讨。并对吸附动力结果进行了一级和二级动力学方程拟合。二级拟和的线性相关系数明显高于一级。说明不同材料对本研究中所使用的高氯酸盐的吸附更符合二级动力学方程。对吸附速率的比较则得出,阴离子交换树脂和活性炭的吸附速率要明显高于其他吸附材料。

Comparative study on removal effect of perchlorate inwater by different adsorbents

The paper compared the adsorption capacity of 8different adsorbents for perchlorate through adsorption isotherm test. Results indicate that perchlorate adsorption effect of Langmuir model is much better than that of Freundlich. The adsorption type of Perchlorate is single layer. The free energy of adsorption of different adsorption materials of perchlorate was calculated. The adsorption of perchlorate is chemical adsorption. As far as adsorption capacities is concerned for these 8adsorbents, it follows the order of anion exchange resin>wood-based activated carbon>coconut-based activated carbon>coal-based activated carbon>chitosan>zeolite>bentonite>granular ferric hydroxide. The kinetics of perchorate adsorption was also studied in this research. Results were fitted to pseudo-first order and pseudo-second order kinetics. Pseudo-second order reaction showed a much higher correlation coefficient than first order which indicates that the adsorption of perchlorate of different materials accord with the equation of second dynamic. The adsorption rate of anion exchange resin and activated carbon is much higher than that of other materials.