Removal of vanadate anion by calcined Mg/Al-CO_3 layered double hydroxide in aqueous solution

作     者：宋海磊 焦飞鹏 蒋新宇 于金刚 陈晓青 杜邵龙 Hai-lei SONG;Fei-peng JIAO;Xin-yu JIANG;Jin-gang YU;Xiao-qing CHEN;Shao-long DU

作者机构：中南大学化学化工学院长沙410083 

出 版 物：《Transactions of Nonferrous Metals Society of China》 (中国有色金属学报（英文版）)

年 卷 期：2013年第23卷第11期

页      面：3337-3345页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 

基　　金：Projects(21176263 21175155)supported by the National Natural Science Foundation of China 

主　　题：layered double hydroxide vanadate adsorption kinetics thermodynamics 

摘      要：Mg/Al-CO3 layered double hydroxide （LDH2） with Mg（II）：Al（III） molar ratio of 2：1 was synthesized by co-precipitation method and its calcined product Mg2Al-CLDH（CLDH2） was prepared by heating Mg2Al-LDH at 773 K for 6 h. Removal of vanadate anion （ 3-4VO ） from aqueous solution on CLDH2 was studied. Batch studies were carried out to address various experimental parameters such as Mg/Al molar ratio, adsorbent dosage, initial concentration of solution, contact time and temperature. Vanadate was removed effectively at the optimized experimental conditions. The adsorption kinetics data fitted the pseudo-first-order model. Isotherms for adsorption vanadate by CLDH2 at different solution temperatures were well described using the Langmuir and Freundlich equations, and the isotherm parameters were calculated using linear regression analysis. The adsorption data fitted the langmuir model with good values of the correlation coefficient （R2〉0.999）. The negative value ofΔGΘand the positive value ofΔHΘindicate that the adsorption processes are spontaneous endothermic in nature. The mechanism of adsorption suggests that the surface adsorption is the main process.