地聚合物水泥固化重金属的研究

Study on the Solidification of Heavy Metals by Fly Ash Based Geopolymers

以粉煤灰为主要原材料,合成了一系列含有重金属的地聚合物,并根据固体废弃物的毒性溶出程序,检验了Cu(Ⅱ),Zn(Ⅱ),Pb(Ⅱ),Cd(Ⅱ),Cr(Ⅲ)和Ni(Ⅱ)在地聚合物中的固化效果.试验结果表明,地聚合物对上述重金属有很好的固化效果.利用X射线衍射(XRD)、傅立叶变换红外(FTIR)、扫描电镜(SEM)等对其结构进行分析后发现,地聚合物固化重金属的机理为物理固封和化学键连的共同作用.

By using fly ash as basic ingredient, a series of fly ash based geopolymeric matrices were synthesized and some experimental evidences about immobilization efficiencies of heavy metals such as Cu（Ⅱ）, Zn（Ⅱ）, Pb（Ⅱ）, Cd（Ⅱ）, Cr（Ⅲ） and Ni（Ⅱ） were presented. According to the toxicity characteristic leaching procedure （TCLP）, it is found that these heavy metals can be effectively solidified into the geopolymeric matrices. Through the results of X-ray diffraction （XRD）, scanning electron microscopy （SEM） and infrared spectroscopy （FTIR）, it is concluded that the solidification mechanism of geopolymer to these heavy metals is a combination of chemical bond and physical encapsulation.