ZnAl-LDH/Al(OH)_(3)复合材料的制备及其对废水中Pb^(2+)的去除性能

Fabrication of ZnAl-LDH/Al(OH)_(3)composite and its Pb^(2+) removal property from wastewater

利用共沉淀法,以Zn(NO_(3))_(2)和Al(NO_(3))_(3)为原料成功制备了锌铝复合材料ZnAl-LDH/Al(OH)_(3)(标记为ZAL/AH),采用SEM表征了ZAL/AH的形貌,利用FTIR、XPS和XRD分析了样品的结构及组成。结果表明,所制备的ZAL/AH为片状结构,相组成受投料比的影响。其中,ZAL/AH-1具有高的比表面积,达到82.7 m^(2)·g^(-1)。同时,利用所制备的复合材料ZAL/AH对水中的Pb^(2+)离子进行了吸附实验,ZAL/AH-1对Pb^(2+)的去除率能够达到95%。对吸附结果进行了吸附动力学、Freundlich和Langmuir模型拟合,Langmuir拟合计算得到的最大吸附量为143.3 mg·g^(-1)。

The composite of ZnAl-LDH/Al(OH)_(3)(marked as ZAL/AH)was successfully prepared using co-precipitation method from the mixture of Zn(NO_(3))_(2)and Al(NO_(3))_(3).Samples were characterized by SEM,FT-IR,XPS and XRD,and the morphology,structure and components of ZAL/AH were analyzed.The results showed that ZAL/AH had lamellar structure,and its phase composition was determined by the feeding molar ratio of Zn(NO_(3))_(2)and Al(NO_(3))_(3).The prepared ZAL/AH-1 had large specific surface area of 82.7 m^(2)·g^(-1).Meanwhile,the experiments of up-taking of Pb^(2+) were also carried out.The removal efficiency toward Pb^(2+) could reach 95%in the case of ZAL/AH-1.Kinetic models,Freundlich and Langmuir models were used to fit the adsorption process.The Langmuir model was found more suitable to describe the removal process,where the calculated maximum adsorption capacity was 143.3 mg·g^(-1).