锆柱撑蒙脱土大孔材料的制备及性能研究

The Preparation and Properties of Zr-pillared Montmorillonite Macroporous Materials

摘要:

采用干压成型法和造孔剂结合将锆柱撑蒙脱土（Zr-MMT）成型为大孔吸附材料（P-ZMt），采用X射线衍射（XRD）、扫描电子显微镜（SEM）、热重分析仪（TG）和全自动压汞仪对P-ZMt进行表征。研究不同造孔剂配比、造孔剂量、压力对P-ZMt的孔隙率、渗透系数和比表面积的影响，并对P-ZMt吸附Cu2+、Cr3+、Pb2+、Cr6+的效果进行探讨。结果表明：P-ZMt成型的最佳条件为m(聚甲基丙烯酸甲酯)：m(偶氮二酰胺)=1：2，造孔剂质量分数为40%，压力为20MPa，焙烧温度为550℃；P-ZMt孔径介于100~170μm，孔隙率达39.85%，大孔之间相互贯通，且孔壁呈现三维蜂窝状孔隙；当吸附剂投加量为1g/L时，P-ZMt对Cr3+、Cu2+、Pb2+去除率均大于90%，而对Cr6+几乎不吸附。

Abstract:

In the present study, a novel Zr-pillared montmorillonite(Zr-MMT) macroporous materials (P-ZMt) was developed by dry pressing molding combining with pore forming agent. The structure and morphologies of P-ZMt was characterized by X-ray diffraction(XRD), scanning electron microscope(SEM), the thermal properties of samples were studied by thermal gravimetric analysis (TG), and the porosity of P-ZMt was detected by mercury porosimetry analyzer. The influence of porosity, permeability coefficient and specific surface area(SSA) including the mass ratio of different pore forming agent, pore forming agent dosage, pressure on of P-ZMt were evaluated. The adsorption of Cu2+, Cr3+, Pb2+, Cr6+ on P-ZMt was discussed. The optimum conditions for forming P-ZMt were: m(PMMA):m(AC)= 1:2, w(pore forming agent)=40%, pressure and calcination temperature were 20MPa and 550C, respectively. The pore size of P-ZMt varied from around 150μm to 250μm and the porosity up to 39.85%. The macropore of P-ZMt were interpenetration and the hole wall rendering three-dimensional honeycomb pore. When the adsorbent dosage was 1g/L, the removal rates of P-ZMt for Cr3+, Cu2+, Pb2+ were over 90%, while for Cr6+ almost no adsorption.