改性陶粒对水中卡马西平去除的动态吸附实验及模型

用CTMAB(十六烷三甲基溴化铵)对陶粒进行改性,以卡马西平(CBZ)为目标污染物,研究了吸附去除饮用水中CBZ的性能并探讨了其应用的可行性。通过滤料吸附去除CBZ的动态实验,发现改性陶粒的去除效果优于陶粒。进水CBZ浓度为2 μg·L-1时,改性陶粒对CBZ的去除率最高为50%,陶粒最高的去除率为40%。研究了滤料再生对吸附性能的影响,发现陶粒和改性陶粒对CBZ的去除均随再生次数的增加而降低,改性陶粒的去除效果仍优于陶粒,改性陶粒的使用期限更长久。讨论了修正前后的Thomas模型,推导得到能更准确描述穿透曲线的Thomas模型取值范围。滤料穿透曲线用原始Thomas模型能很好地计算的速率常数kTh和平衡吸附量q0。利用原始Thomas模型也能较为准确地预测滤柱的穿透时间。

Experiments and model for dynamic adsorption of carbamazepine onto modified ceramisite in drinking water

The performance of ceramisite modified by cetyltrimethylammonium bromide(CTMAB) regarding carbamazepine(CBZ) removal from drinking water and its application feasibility were evaluated in this study.The results of the dynamic experiments showed that the CBZ removal efficiency using modified ceramisite was better than that of original one.When the influent CBZ concentration was 2 μg·L-1,the CBZ removal efficiency using modified ceramisite was up to 50%,while the removal efficiency of unmodified ceramisite was only up to 40%.Experiments were also performed to examine the impact of filter regeneration on adsorption performance.The results showed that although the CBZ removal efficiency using modified and unmodified ceramisite both decreased with increasing regeneration times,the modified ceramisite still had a better removal efficiency and longer life span compared with the unmodified one.The differences between simplified and original Thomas model were discussed,and a more accurate value range for describing breakthrough curves using Thomas model has been inferred.Compared with the simplified Thomas model,the breakthrough curve generated by the original Thomas model is better for calculating the adsorption rate constant(kTh) and the capacity of equilibrium adsorption(q0) in this experiment.The breakthrough time of the filter column can also be predicted more accurately using the original Thomas model.