脂肪胺-硅胶的制备与其吸附Pb(Ⅱ)性能

Synthesis of silica modified with aliphatic amine and its adsorption for Pb(Ⅱ)

该研究以二氧化硅、γ-氨丙基三乙氧基硅烷、甲基丙烯酸甲酯和乙二胺为原料合成了脂肪胺-硅胶树脂,并利用FTIR、TG对其结构及官能团接枝率进行分析;利用所制备的脂肪胺-硅胶材料进行了重金属离子Pb(Ⅱ)的吸附研究,考察了吸附时间、温度、p H值及重金属离子对吸附的影响,并利用Langmuir和Freundlich吸附等温方程进行拟合.结果表明,该材料对Pb(Ⅱ)的吸附量达到1.67 mmol·g^(-1);合成树脂对Pb(Ⅱ)的吸附过程可用Langmuir吸附等温方程进行拟合,根据G.E.Boyd方程可知,吸附过程符合液膜扩散控制机理.

Silica modified with aliphatic amine was prepared using silica gel,（3-aminopropyl）triethyloxysilane,ethylenediamine and methyl methacrylate as raw materials.Its structure and grafting ratio of functional groups were characterized by Fourier-transform infrared spectra（FTIR）and thermogravimetry（TG）.The adsorption properties of the modified silica gel for Pb（Ⅱ） was investigated,and the effects of the adsorption time,p H,temperature and initial concentration on the adsorption were studied by the single factor experiments.Furthermore,Langmuir and Freundlich isotherm models were applied to analyze the experimental data.The result exhibited that the maximum adsorption capacity for Pb（Ⅱ） was 1.67 mmol·g-1.The adsorption isotherms were obtained and were fitted to Langmuir equation.In addition,the adsorption process conformed to G.E.Boyd equation,showing that the process followed liquid membrane diffusion mechanism.