Mg-Al-Ce水滑石吸附去除水中的硼

用共沉淀法成功制备了镁铝铈水滑石(Mg-Al-Ce-HT), 采用不同分析手段对材料进行表征。通过静态吸附实验研究了Mg-Al-Ce-HT的吸附效率与初始pH、吸附剂剂量、初始硼酸浓度和接触时间的关系。当pH小于8.0时, 溶液的pH对硼吸附几乎没有影响, 当pH超过8.0时, 吸附容量降低。吸附剂的最佳用量为200 mg, 最大吸附容量为32.52 mg·g ^-1。 硼去除量在160 min内达到平衡。吸附等温线表明吸附过程是一个非自发的吸热过程。吸附数据与Langmuir模型拟合良好, 表明吸附是单层吸附。

Removal of Boron from Water by Mg-Al-Ce Hydrotalcite Adsorption

Boron is an important micronutrient for plants,animals,and humans.However,high concentrations of boron are harmful to animals and plants.A magnesium-aluminum-cerium hydrotalcite(Mg-Al-Ce-HT)was successfully prepared by the co-precipitation method for boron removal.Different analyses were conducted to confirm the structure and characteristics of Mg-Al-Ce-HT.Adsorption efficiency of Mg-Al-Ce-HT was studied as a function of initial pH,amount of adsorbent,concentration of initial boric acid,and contact time.The pH of the solution had a negligible effect on boron sorption when pH was less than 8.0.However,the adsorption capacity decreased when the pH exceeded 8.0.The optimum amount of the adsorbent was 200 mg,and the maximum adsorption capacity was 32.52 mg·g–1.Boron removal reached equilibrium at 160 min.The thermodynamic parameters revealed that the adsorption was a non-spontaneous and endothermic process.The data fitted well with the Langmuir model,which indicated that the process involved monolayer adsorption.