| 摘要: |
| 利用高钙粉煤灰研制地聚合物来固化/稳定重金属离子，研究了高钙粉煤灰地聚合物对重金属离子的固化/稳定效果，并进一步初探了高钙粉煤灰地聚合物对重金属离子的固化/稳定作用机制.研究表明：高钙粉煤灰地聚合物分别固化/稳定质量分数为0.025%的Pb（Ⅱ），0.025%的Cr（Ⅵ）和0.010%的Hg（Ⅱ）后，重金属离子的浸出浓度远低于规定的上限值，固化率均在98%（质量分数）以上；高钙粉煤灰地聚合物固化/稳定重金属离子后，有无定形的地聚合物凝胶及类沸石矿物CaAl2Si2O8·4H2O生成，重金属阳离子部分置换了Na+或Ca2+，被键合在地聚合物的网状结构中，引起了分子基团的显著变化；在无定形凝胶之间分别出现了细丝状、膨化状以及粒状产物. |
| 关键词: 高钙粉煤灰 地聚合物 重金属离子 浸出浓度 作用机制 |
| DOI：10.3969/j.issn.1007 9629.2012.06.004 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(51172164，51208370）；高等学校博士学科点专项科研基金资助项目（20090072110010，20110072120046） |
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| Research on Solidification/Stabilization of Heavy Metal Ions by Class C Fly Ash Geopolymer |
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GUO Xiao lu, SHI Hui sheng
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Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Tongji University, Shanghai 201804, China
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| Abstract: |
| Class C fly ash was used to prepare the geopolymer for solidification and stabilization of the heavy metal ions. The effect of the solidification and stabilization of heavy metal ions by class C fly ash geopolymer was investigated and its mechanism was discussed. The results show that after solidification and stabilization of 0.025%(by mass) of Pb(Ⅱ),0.025%(by mass)of Cr(Ⅵ) and 0.010%(by mass) of Hg(Ⅱ) by class C fly ash geopolymer,the leaching concentrations of heavy metal ions are far lower than the upper limit, and all the solidified/stabilized ratios of heavy metal ions reach 98%. Amorphous geopolymeric gel and similar zeolite mineral of CaAl2Si2O8 ·4H2O are formed when the geopolymer solidified/stabilized the heavy metal ions. Cations of heavy metal partly replace Na+ or Ca2+ and are bond in the geopolymeric network with the result that the molecule radical is significantly changed. When the geopolymer solidified/stabilized Cr(Ⅵ), Pb(Ⅱ), and Hg(Ⅱ) the filamentous product, swelling product, and granule product are observed among the amorphous gel. |
| Key words: class C fly ash(CFA) geopolymer heavy metal ion leaching concentration mechanism |
