種々の pH 条件で調製したポートランダイト懸濁液によるクロム(VI)エトリンガイトの合成
種々の pH 条件で調製したポートランダイト懸濁液によるクロム(VI)エトリンガイトの合成
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使用在不同 pH 条件下制备的硅钙石悬浮液合成六价铬钙矾石
DOI：
10.2109/jcersj.114.299
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
攻 池田
中科院分区：
文献类型：
--
作者：
徹 寺井;彰 三国;隆一 小松;攻 池田
在波特兰石悬浮液中合成Cr(VI)-钙矾石，用于固定化有害六价Cr。将NaAlO2和CrO3试剂溶解于去离子水中，得到0.1 mol/L溶液，与波特兰石悬浮液混合，在无co2的合成空气中室温搅拌3 h。Ca/Al原子比为1.0 ~ 5.0，Cr/Al原子比为1.0、1.5和2.0。用XRD、XRF、FE-SEM等方法对运行产物进行评价。结果表明，Cr(VI)-钙矾石在pH为10.9的条件下生成，且更多地与方解石结合。方解石的形成也是由于在环境空气中干燥过程中残留的硅酸盐Ca(OH)2的碳化作用。Cr(VI)-钙矾石的计算产率一般超过80质量%，化学计量混合物的产率达到85.6质量%。在pH值低于10.9的条件下，未发现Cr(VI)-钙矾石，XRF分析显示，除了游离的cro3电位外，游离的cao和游离的al2o3电位分别对应于方解石、不良结晶的三水铝石（三水铝石凝胶）和可溶性的铬铁矿CaCrO4吸附和捕获在果冻型三水铝石凝胶中。
The synthesis of Cr(VI)-ettringite was attempted in portlandite suspensions for the immobilization of hazardous hexavalent Cr. The reagents NaAlO2 and CrO3 were used by dissolving them in deionized water to obtain 0.1 mol/L solutions, which were mixed with portlandite suspensions and stirred for 3 h at room temperature in CO2-free synthetic air. Ca/Al atomic ratios were varied from 1.0 to 5.0 against the Cr/Al atomic ratios 1.0, 1.5 and 2.0. Run products were evaluated by XRD, XRF and FE-SEM. The results showed that Cr(VI)-ettringite formed under the conditions of pH 10.9 and more always associates with calcite. The calcite was also formed due to the carbonation of the remaining portlandite Ca(OH)2 during drying in ambient air. The calculated yields of Cr(VI)-ettringite generally exceeded 80 mass%, and 85.6 mass% was reached for the stoichiometric mixture. In the run products obtained at pH lower than 10.9, no Cr(VI)-ettringite was identified, and the XRF analysis showed free-CaO and free-Al2O3 other than free-CrO3 potentials each corresponding to calcite, ill-crystallized gibbsite (gibbsite gels) and the soluble chromatite CaCrO4 adsorbed and trapped in the jelly gibbsite gels.