Al-MCM-41的制备及其对镉的吸附

The Synthesis of Al-MCM-41 for Cadmium(Ⅱ) Removal

为探究介孔材料对水溶液中镉的吸附效果,采用粉煤灰作为原料提取硅源,十六烷基三甲基溴化铵作为模板剂,采用水热合成法制备了MCM-41和Al-MCM-41。运用多种表征手段对其进行分析,如X射线衍射(XRD)、比表面积分析(BET)及红外光谱(FTIR),同时考查温度、吸附剂投加量、pH等因素对Cd2+吸附效果的影响。结果表明,负载铝之后的Al-MCM-41吸附剂具有稳定的二维六方介孔结构,比表面积为782.3m2/g,孔容为0.89cm3/g,孔径为3.27nm。Al-MCM-41对Cd2+吸附受温度影响较小,受pH影响较大,当pH=7时,吸附量最大,为27.57mg/g,Cd2+的吸附动力学过程符合准二级动力学模型。

In this study fly ash was used as raw material to prepare MCM-41 and Al-MCM-41 by hydrothermal synthesis. It was analyzed by various characterization methods, such as X-ray diffraction (XRD), specific surface area analysis (BET) and infrared spectroscopy (FTIR), and effects of temperature, adsorbent dosage and pH on the adsorption of Cd2+ were investigated. The results show that the Al-MCM-41 adsorbenthad uniform hexagonal channels with a specific surface area of 782.3 m2/g, a pore volume of 0.89 cm3/g and a pore diameter of 3.27 nm. The adsorption of Cd2+ by Al-MCM-41 was less affected by temperature. When pH=7, the adsorption amount was the highest, which was 27.57 mg/g. The adsorption kinetics of Cd2+ accorded with the quasi-secondary kinetic model.