铁基柱撑蒙脱石的制备及其应用于芘吸附的研究

Preparation of Fe-pillared montmorillonite and its application in the adsorption of pyrene

摘要:

以钙基蒙脱石（Ca-MMT）、硫酸亚铁作原料，通过柱撑、煅烧方式制备铁基柱撑纳米蒙脱石(Fe-MMT)，利用SEM、TEM、XRD、TGA等手段对样品结构进行表征，考察了Fe-MMT、Ca-MMT吸附性能的变化，探究了其对吸附多环芳烃的机理。结果表明：相对于Ca-MMT，Fe-MMT结晶度降低，但热稳定性增强。表面形貌发生变化，铁元素取代部分钙元素，铁元素含量达到5.597%，铁元素吸附率达到99.95%。 Ca-MMT总比表面积为29.86 m2/g，而Fe-MMT比表面积上升至51.29 m2/g。相应地，Ca-MMT吸附芘的容量约为15.00 mg/g，而Fe-MMT吸附芘分子的容量升高至95.43 mg/g，吸附芘的容量明显增加。5次循环利用后其Fe-MMT吸附容量仍然能达到0.709 mg/g， 维持在初始吸附量的88%以上，具有可循环利用性。由此推断出：应用此方法制备的Fe-MMT具有应用于疏水性有机污染物去除的潜力。

Abstract:

Fe-pillared montmorillonite(Fe-MMT) was prepared with Ca-montmorillonite(Ca-MMT), ferrous sulfate as the original materials by calcination. The ultrastructures of prepared Fe-MMT were characterized by SEM, TEM, XRD and TGA. The results showed that the crystallinity decreased after calcination of the prepared Fe-MMT, but the thermal stability intensified. The morphology showed distinct characters, and a fraction of Fe substituted Ca resulted in the increased distribution of Fe, with its contents reaching 5.597% which meant 99.95% of Fe was inserted. The specific surface area for Ca-MMT was 29.86 m2/g, but it was increased to 51.29 m2/g for. Furthermore, the adsorption capacity was assessed, and it reached 95.43 mg/g for Fe-MMT, which was dramatically larger than that of Ca-MMT with a value of 15.00 mg/g. Additionally, it can still adsorb more than 88% of pyrene after 5 cycles of application, with the capacity kept at 0.709 mg/g. The results above indicated that the prepared Fe-MMT could be potentially applied in the removal of organic pollutants.