Mg/Al双金属氧化物对As(V)吸附性能的研究

研究了以镁铝水滑石为原料制备的Mg/Al双金属氧化物对溶液中As(V)的吸附作用及其影响因素.结果表明：Mg/Al双金属氧化物对As(V)具有较强的吸附能力，吸附规律符合Langmuir等温吸附方程，根据计算所得的理论最大吸附量为51.02 mg·g-1，与实验得出的最大吸附量50.53 mg·g-1基本一致；运用3种...

Adsorption of arsenate from aqueous solution by Mg/Al layered double oxide

The adsorption characteristics of arsenate from aqueous solution by the Mg/Al layered double oxide (Mg/Al-LDO) and its influencing factors, such as the pH of aqueous solution, dosage of Mg/Al-LDO, equilibrium isotherm and adsorption kinetic, were studied. The results showed that the adsorption of arsenate by Mg/Al-LDO was consistent with the Langmuir isotherm. The maximum adsorption capacity of Mg/Al-LDO for arsenate was 50.53 mg · g^-1, close to the stoichiometric adsorption (51.02 mg · g^-1). Three kinetic models were used to fit the experimental data, indicating that the pseudo-second-order kinetics model could better describe the adsorption process. The pH of arsenate solutions has an significant effect on the adsorption if As(V) with the maximum removal rate found at pH=2.0, The results by X-ray diffraction (XRD) and scanning electronic microscopy (SEM) showed that the Mg/Al-LDO lost a typical structure of layered double hydroxides after calcining, and then the partial layered structure of layered double hydroxides was recovered after adsorbing arsenate. The removal arsenate mechanism of Mg/Al-LDO is mainly attributed to the reconstruction of its original layered structure in the presence of appropriate anions and co-precipitation with Mg/Al oxides.