片状钛酸镁钾的制备及其去除污水中铜离子的应用

摘要

采用熔盐法制备片状钛酸镁钾(K0.8Mg0.4Ti1.6O4, KMTO)，并将其应用于去除污水中的Cu(II)离子。分别采用XRD、SEM和TEM等技术对样品的晶相组成、形貌和结构进行表征。研究不同pH 值和初始铜离子浓度对铜离子吸附行为的影响。结果显示，铜离子的最大饱和吸附量可达到290.67 mg/g，采用KMTO可以去除溶液中几乎99.9%的铜离子。该结果优于其他文献报道的离子去除剂的结果。KMTO 对铜离子的吸附动力学研究结果显示，钛酸镁钾对铜离子的吸附符合拟二级反应动力学方程，而其吸附等温数据可以用Freundlich方程很好地进行拟合(R2=0.991)。研究结果表明，片状钛酸镁钾在处理污水中的重金属离子方面具有很好的应用前景，为片状钛酸镁钾开辟了新的应用领域。%Platy potassium magnesium titanate (K0.8Mg0.4Ti1.6O4, KMTO) was synthesized by a flux method. The potential application of KMTO in removing copper ions from water pollutants was investigated. The crystal phases of specimens were identified by XRD. The morphology and structural information were characterized by SEM and TEM. The adsorption behavior under different conditions was investigated, including different pH values and different initial copper ion concentrations. The results show that the maximum adsorption capacity of Cu(II) ions is 290.697 mg/g, and almost 99.9% of Cu(II) ions can be removed, which is much higher than that of other sorbents reported. The kinetics of KMTO for the adsorption of Cu(II)ions was studied and the best fit can be obtained by the pseudo-second-order model. Adsorption isothermal data can be well interpreted by the Freundlich equation (R2=0.991). In conclusion, this study highlights that KMTO is a potential material for the efficient removal of heavy metal ions in polluted water. It also opens up a new opportunity for the applications of platy KMTO.