【摘要】 用3-巯丙基三甲氧基硅烷(MPTMS)对13X分子筛表面进行修饰,采用XRD和FT-IR测试方法对功能化前后的分子筛结构进行表征,结果表明,功能化后分子筛在保持原有结构同时表面还接枝了对Pb2+离子有吸附能力的巯基基团。吸附实验表明,巯基功能化分子筛对水中Pb2+离子比原分子筛具有更强的吸附去除效果,饱和吸附容量和去除率提高近一倍。SH-13X对Pb2+离子的等温吸附符合Langmuir模型,最大吸附容量为47.01 mg/g,吸附强度b为2.26。动力学分析表明SH-13X对Pb2+离子的吸附过程更符合准二级动力学模型,而且粒内扩散不是该吸附过程的主要吸附机制。溶液中的Pb2+与嫁接在分子筛表面及孔口位置的-SH功能团形成配位络合物而去除。更多还原

【Abstract】 13X zeolite was modified by 3-mercaptopropyltrimethoxysilane(MPTMS).The structure of materials before and after functionalization was investigated by X-ray powder diffraction(XRD) and fourier transform infrared spectroscopy(FT-IR).The results show that the functionalized materials still kept the original structure and morphology,and at the same time the materials had grafted some thiol-groups which had strong binding ability for Pb2+ in aqueous solution.It is verified by the adsorption experiment that thiol-functional materials have better efficient treatment of Pb2+ than the raw materials.The sorption isotherm of Pb2+ on SH-13X zeolite followed the Langmuir model.The maximum sorption capacity was 47.01 mg/g and absorptive intensity was 2.26.Kinetic analysis gives out that the pseudo-second-order equation provided the best fit to experimental data,and intra-particle diffusion was not the dominate mechanism in this adsorption process.Pb2+ in aqueous solution was removed with thiol-ligands on the surfaces of zeolite and the entrances of holes.更多还原