摘要
在磷石膏基水泥中加入氢氧化镁,以提高其抗碳化性能,运用XRD、SEM等测试方法对其水化过程和机理进行了探讨。结果表明,当氢氧化镁掺量达到8%后,水泥碳化7d后的强度高于碳化前的强度,且随氢氧化镁掺量的增加碳化深度逐渐减小。氢氧化镁与二氧化碳反应生成碳酸镁,堵塞水泥石中的孔隙,阻止了二氧化碳的渗入,保护了体系中的钙矾石不被二氧化碳大量分解,使水泥石更加致密,是氢氧化镁能够改善磷石膏基水泥抗碳化性能的主要原因。
The magnesium hydroxide was added into phosphogypsum-based cement to improve its carbonation resistance. The hydration process and mechanism of the phosphogypsum-based cement were studied by XRD and SEM. The results showed that the strength of cement after carbonization 7d was better than that of before been carbonized when the content of magnesium hydroxide exceed 8%, moreover, the carbonation depth decreased with the magnesium hydroxide content increased. The reaction of magnesium hydroxide and carbon dioxide generates magnesium carbonate, which plugs the pores of cement stone, so as to prevent the infiltration of carbon dioxide and the decomposition of ettringite. The magnesium hydroxide could make cement stone more dense, which was the main reason that magnesium hydroxide could improve the carbonation resistance of phosphogypsum-based cement.
出处
《水泥》
CAS
北大核心
2011年第11期14-18,共5页
Cement
关键词
磷石膏
氢氧化镁
碳化
phosphogypsum
magnesium hydroxide
carbonation
