X射线衍射Rietveld全谱拟合法定量检测滑石混合矿物中滑石含量  

Quantitative determination of talc in talc mixed ore by X-ray diffraction Rietveld full spectrum fitting method

作　　者：周君龙 陈宜浩 李全忠 赵泉 唐志锟 宋武元 ZHOU Junlong;CHEN Yihao;LI Quanzhong;ZHAO Quan;TANG Zhikun;SONG Wuyuan(Guangzhou Customs Technology Center,Guangzhou 510623,China)

机构地区：[1]广州海关技术中心,广东广州510623

出　　处：《冶金分析》2023年第4期18-23,共6页Metallurgical Analysis

基　　金：国家重点研发计划项目(2018YFF0215400)。

摘　　要：在我国出口监管中,滑石质量分数50%以上的混合矿物需按滑石管理,实行出口许可证制度,目前对滑石的检测只是镁、硅等元素含量,无法对滑石进行定量,故实验建立了采用X射线衍射(XRD)结合Rietveld全谱拟合定量检测滑石混合矿中滑石含量的方法。采用XRD在日常检测样品中筛选出纯的滑石粉、白云石、方解石、石英、方石英、青红石等样品,以上述样品作为标准样品制备一系列比例的混元体系,以XRD结合Rietveld全谱拟合考察上述混元体系中滑石的含量,拟合结果与已知混元体系滑石含量差值在-0.9%~0.3%之间,结果较为接近,可见,以XRD结合Rietveld全谱拟合检测滑石混合矿物中滑石含量具有一定的可行性。以实验方法对近年来经广州口岸出口的部分滑石混合矿物进行检测,并从中选出滑石含量低、中、高3个梯度的样品进行加标回收,回收率在90%~120%之间;另对选出的中梯度样品进行精密度考察,滑石含量测定结果的相对标准偏差(RSD,n=10)为0.94%,满足YB/T 56320—2006的要求。实验方法可以满足滑石矿物出口监管需求。In China′s export supervision,the mixed ore with talc content higher than 50%should be managed as talc,and the export license system is implemented.At present,the detection of talc only includes the determination of magnesium and silicon contents,which cannot meet the quantitative analysis requirements of talc.Therefore,the method for the quantitative determination of talc in talc mixed ore by X-ray diffraction(XRD)Rietveld full spectrum fitting was established.Pure samples of talc powder,dolomite,calcite,quartz,cristobalite,rutile and other samples were screened from daily test samples by XRD.A series of mixture system with different ratios were prepared using the above samples as standard samples.The content of talc in the prepared mixture system was investigated by XRD combined with Rietveld full spectrum fitting.The different between the fitting values and the talc contents in the known mixture system ranged from-0.9%to 0.3%,which meant that the results were close.Therefore,it was feasible to detect talc content in talc mixed ore by XRD combined with Rietveld full spectrum fitting.The proposed method was applied to the detection of some talc mixed ore exported through Guangzhou Port in recent years.The samples with low,medium and high talc content were selected for the standard addition experiments.It was found that the recoveries were between 90%and 120%.In addition,the selected samples with medium gradient were used for precision tests.The relative standard deviation(RSD,n=10)of determination results was 0.94%,which could meet the requirements in YB/T 56320-2006.The proposed method could meet the export supervision requirements of talc ore.

关 键 词：滑石混合矿物 滑石含量 X射线衍射(XRD) Rietveld全谱拟合 混元体系 

分 类 号：O657.62[理学—分析化学] TF031[理学—化学]