不同硫酸盐浓度下钙矾石对Cr离子的固化作用  

Solidification of Cr Ions by Ettringite at Different Sulfate Concentrations

作　　者：王昕[1,2] 崔素萍 颜碧兰[2] 汪澜 张金山 WANG Xin;CUI Suping;YAN Bilan;WANG Lan;ZHANG Jinshan(College of Materials Science and Engineering,Beijing University of Technology,Beijing 100022,China;China Building Materials Academy,Beijing 100024,China)

机构地区：[1]北京工业大学材料科学与工程学院,北京100022 [2]中国建筑材料科学研究总院有限公司,北京100024

出　　处：《建筑材料学报》2019年第6期878-885,共8页Journal of Building Materials

基　　金：国家重点基础研究(973)项目(2010CB735803)

摘　　要：借助X射线衍射(XRD)、红外光谱(IR)、扫描量热(DSC)、扫描电镜(SEM)、电感耦合等离子发射光谱仪(ICP)等测试方法,分析了不同硫酸盐浓度下钙矾石对不同价态Cr离子的固化作用.结果表明:在水化液相中SO4^2-浓度适宜条件下,钙矾石对低掺量(0.5%)、不同价态Cr离子的28 d固化率均达85%或以上,Cr离子掺量增至2.0%时,钙矾石对Cr(Ⅲ)的固化率变化不大,而对Cr(Ⅵ)的28 d固化率降至38.6%;水化液相中SO4^2-浓度较低时,钙矾石对Cr(Ⅵ)的固化能力有所增强;无论液相中SO4^2-浓度适宜与否,Cr(Ⅲ)和Cr(Ⅵ)对钙矾石晶体结构和晶体形态均产生了不同程度的影响,且Cr(Ⅲ)影响较Cr(Ⅵ)显著;液相中SO4^2-浓度不同,Cr离子对钙矾石晶体形态影响程度也不相同,其中,液相中SO4^2-浓度较低时,Cr(Ⅲ)掺入对钙矾石晶体c轴方向的生长发育有明显促进作用,且在一定程度上提高了钙矾石结晶程度与热稳定性.The solidification of ettringite on the chromium ions with different valence states and species under the condition of different sulfate concentrations were investigated by means of XRD,IR analysis,DSC,SEM,ICP and other method.The results showed that the ettringite solidification rate for the low dosage(0.5%)of chromium ions with different valence and species was add up to 85% or more.The solidification rate of ettringite to Cr(Ⅲ)changed little,while the solidification rate to Cr(Ⅵ)28 d decreased to 38.6% when the dosage of chromium ions increased to 2.0%.The solidification ability of ettringite to Cr(Ⅵ)was improved when the concentrations of SO4^2- ions were low in the hydrated liquid phase.No matter what concentration of SO4^2- ions was in the hydrated liquid phase,Cr(Ⅲ)and Cr(Ⅵ)had a different effects on the crystal structure and morphology of ettringite,and that of Cr(Ⅲ)was more obvious.The effect of Cr ions on ettringite crystal morphology was also different.When the concentrations of SO4^2- ions were low in the hydrated liquid phase,the doping of Cr(Ⅲ)could obviously promote the growth and development of ettringite crystal in the c-axis direction,and improve the crystallization degree and thermal stability of ettringite to a certain extent.

关 键 词：钙矾石 Cr离子 硫酸根离子 固化 结构 

分 类 号：O482[理学—固体物理] O614[理学—物理]