MgO/SiO_2纳米复合材料同步吸附亚甲基蓝和Cu~(2+)

采用化学沉积法合成了MgO/SiO_2纳米复合材料,通过扫描电子显微镜和X射线能谱分析(SEM-EDX)、X射线衍射(XRD)、Zeta电位仪、FTIR等方法对其进行了表征。研究了MgO/SiO_2对亚甲基蓝(MB)和Cu~(2+)的吸附行为及同步吸附效果。表征结果表明:MgO/SiO_2为褶皱、凸起的球形形貌;MgO成功负载在SiO_2表面。实验结果表明:MgO/SiO_2对MB和Cu~(2+)的吸附符合准二级动力学模型和Langmuir等温吸附模型,MB和Cu~(2+)的饱和吸附量分别为83.72 mg/g和208.70 mg/g;MB和Cu~(2+)的同步吸附在MgO/SiO_2表面存在竞争关系;在溶液体积为30m L、MgO/SiO_2加入量为10 mg、MB质量浓度为10 mg/L或Cu~(2+)质量浓度为100 mg/L、吸附温度为25℃、吸附时间为24 h、初始溶液pH为4.00、解吸时间为4 h的条件下,MgO/SiO_2第1次吸附MB和Cu~(2+)的去除率分别为92.8%和90.1%,第5次吸附的去除率分别为59.6%和57.4%。

Simultaneous adsorption of methylene blue and Cu2+ using MgO / SiO2 nanocomposite

MgO /SiO₂ nancomposite was synthesized by chemical deposition method and characterized by SEM-EDX,XRD,Zeta potentiometer,and FTIR. The adsorption of methylene blue（MB）and Cu²⁺ on MgO /SiO₂ and their simultaneous adsorption effect were investigated. The characterization results show that：MgO /SiO₂ has spherical morphology with wrinkles and embossment;MgO is successfully loaded onto the surface of SiO₂. The experimental results show that：The adsorption process fits the pseudo-second-order kinetic model and Langmuir isothermal adsorption model,and the saturated adsorption capacity of MB and Cu²⁺ is 83.72 mg/g and 208.70 mg/g respectively;When MB and Cu²⁺ are simultaneously adsorped,a competitive relationship between MB and Cu²⁺ is appeared on the surface of MgO /SiO₂;Under the conditions of solution volume 30 mL,MgO /SiO₂ dosage 10 mg,MB mass concentration 10 mg/L or Cu²⁺ mass concentration 100 mg/L,adsorption 25 ℃,adsorption time 24 h,initial pH 4.00 and desorption time 4 h,the removal rates of MB and Cu²⁺ are 92.8% and 90.1% for the first adsorption,and 59.6% and 57.4% for the fifth adsorption,respectively.