| 摘要: |
| 通过浸出毒性鉴别试验和长期浸出试验分析了碱激发水泥（AAC）对重金属和放射性金属的固化效果，并通过X射线衍射、红外光谱、扫描电镜-能谱等技术分析了重金属铜的加入对AAC产物微观结构的影响。AAC由水泥、硅灰、粉煤灰、磨细矿渣、偏高岭土和氢氧化钾制得。浸出毒性鉴别试验结果说明：所制备的AAC对重金属（铜、铅、镍、锌、镉）均具有较好的固化效果，固化效率在99.97％以上。加入的重金属铜进入到AAC产物中，影响到AAC产物中的O-Si-O键、Al-O-Si键和Si-O-Si键的周围环境，使其振动的频率发生变化，但没有引起AAC产物化学结构上的变化。长期浸出试验结果表明：AAC对放射性金属（锶、铯）的固化效果好于普通水泥，铯的浸出率显著高于同浸出龄期的锶的浸出率，说明铯比锶难以固定。研究表明：碱激发水泥对重金属和放射性金属有较好的固化效果，可以用来固化处理含有重金属和放射性金属的危险废物。 |
| 关键词: 碱激发水泥 重金属 放射性金属 固化 微观结构 |
| DOI： |
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| Solidification Analysis of Heavy Metal and Radioactive Metal by Alkali-Activated Cement |
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LI Ke-liang
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North China University of Water Resources and Electric Power
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| Abstract: |
| Solidification efficiencies of heavy metals and radioactive metals by alkali-activated cement (AAC) were investigated by identification tests for extraction toxicity and long-term leaching tests. The influence of heavy metal to AAC microstructure was analyzed by X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy and energy dispersive. AAC was prepared from cement, silicon fume, metakaolin, fly ash, ground granulated blast-furnace slag and potassium hydroxide. Results from identification tests for extraction toxicity show that AAC has a good capability to solidify heavy metals. Solidification rates of heavy metals including cuprum, plumbum, nickel, zincum and cadmium are above 99.97%. It is proved by FTIR that Cuprum comes into the AAC product and affects vibration frequencies of O-Si-O bond, Al-O-Si bond and Si-O-Si bond in the chemical combination way. But it doesn’t bring any new changes of chemical structure in AAC product. In long-term leaching tests, AAC has higher solidification efficiencies of radioactive metals (cesium and strontium) than cement has. The leaching rates of cesium are always higher than those of strontium at the same leaching age. It is to say that cesium is more difficult to be solidified than strontium. The results show that alkali-activated cement has good solidification efficiencies to heavy metal and radioactive metal and it can be used to solidify hazardous wastes containing heavy metal and radioactive metal. |
| Key words: Alkali-activated cement Heavy metal Radioactive metal Solidification Microstructure |
