XRD内标法测定高镁水泥熟料中方镁石含量和水化程度  

Quantitative determination of periclase and periclase hydration in high magnesium cement clinker with XRD internal standard method

作　　者：许彦明[1] 徐玲玲[1] 李文伟[2] 

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京210009 [2]中国长江三峡集团公司,湖北宜昌443002

出　　处：《南京工业大学学报（自然科学版）》2014年第5期30-35,共6页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家科技支撑计划(2011BAE27B01)

摘　　要：采用X线衍射(XRD)内标法,以ZnO作为内标物对高镁水泥水化浆体中方镁石进行定量分析,并利用回收率评价其准确性。观察方镁石水化膨胀对浆体试块产生的破坏情况,并利用扫描电子显微镜(SEM)观察140 d方镁石水化产物的形貌。结果表明:内标法可以用于定量测定高镁水泥浆体中的方镁石含量并根据测定结果确定方镁石的水化程度。在30℃养护180 d时方镁石水化程度为46.66%,在80℃养护60 d时方镁石的水化程度为86.39%,180 d时达到90.64%,水化趋于完全。SEM观察发现,80℃水化140 d时方镁石颗粒表面有片状水镁石形成。80℃养护条件下,高镁熟料中方镁石水化60 d产生的膨胀对水泥试块产生破坏作用,而养护温度低于38℃时方镁石水化缓慢,水化140 d的高镁水泥浆体试块没有明显的外观变化。A quantitative X-ray diffractometic （XRD） method with ZnO as an internal standard was used for estimating periclase and brucite in high-magnesia cement paste. Recovery was used to evaluate the accuracy. Periclase hydration expansion resulting in slurry block damaging was investegated. The appearance of 140 d periclase hydration was analyzed by scanning electron microscopy （SEM）. Results showed that XRD internal standard method could be used for the determination of periclase and study the degree of periclase hydration in high magnesium cement paste. The degree of periclase hydration was 46.66% in 180 d under 30 ~C, and it was 86.39% in 60 d and was 90. 64% in 180 d under 80 ~C .It was found that the laminate brucite appeared on periclase surface in 140 d under 80 ℃ by SEM. The expansion of periclase hydration resulted in cement block damaging in 60 d under 80 ℃. Periclase hydration was very slow at the temperature lower than 38 ℃, and the influence of slurry block damaging was not significant in 140 d.

关 键 词：高镁熟料 XRD内标法 方镁石 膨胀 

分 类 号：TQ172.1[化学工程—水泥工业]