熔融制样-X射线荧光光谱法测定石墨矿中10种主次量组分  

Determination of 10 major and minor components in graphite ore by X-ray fluorescence spectrometry with fusion sample preparation

作　　者：赵烨 胡艳巧 陈超 张雪梅 徐崇颖 赵良成 ZHAO Ye;HU Yanqiao;CHEN Chao;ZHANG Xuemei;XU Chongying;ZHAO Liangcheng(Hebei Research Center for Geoanalysis,Baoding 071051,China;Key Laboratory of Mineral Resources and Ecological Environment Monitoring Hebei Province,Baoding 071051,China)

机构地区：[1]河北省地质实验测试中心,河北保定071051 [2]河北省矿产资源与生态环境监测重点实验室,河北保定071051

出　　处：《冶金分析》2023年第8期55-62,共8页Metallurgical Analysis

基　　金：保定市科技计划项目(2141ZF323);河北省地质勘查局项目(454-0601-YBN-DONH)。

摘　　要：石墨是一种特殊的非金属材料,广泛应用于航空、航天等行业,石墨矿中杂质元素(除碳以外)对石墨制品的性能有较大影响,应用时需准确测量杂质元素含量。石墨矿样品中固定碳含量高,直接熔融易导致熔片有黑渣和气泡,因此需对样品进行预氧化。实验选择Li_(2)B4O_(7)-LiBO_(2)混合熔剂(质量比1∶1),稀释比为20∶1,滴加4滴300 g/L LiBr溶液为脱模剂,先在800℃预氧化30 min,再1050℃熔融19 min,制备玻璃熔片;选用石墨矿、水系沉积物、岩石、土壤等标准物质/样品得到具有合适梯度范围的系列校准样片,X射线荧光光谱法(XRF)测定石墨矿中Al_(2)O_(3)、SiO_(2)、Fe_(2)O_(3)、MgO、CaO、K2O、Na2O、TiO_(2)、MnO、P等10种主次量组分。实验方法用于测定石墨矿标准物质GBW03118、GBW03120中10种主次量组分,结果的相对标准偏差(RSD)为0.20%~3.7%,测定值与认定值相一致。采用实验方法与行业标准方法JC/T 1021.5—2007测定石墨矿样品,测定结果相一致。Graphite is a special nonmetal material,and it has been widely used in aerospace industries and many other fields.The impurity elements in graphite(except carbon)have great influence on the properties of graphite products.Therefore,it is necessary to accurately determine the contents of impurity elements.The content of fixed carbon in graphite sample is high,which will easily black slag and bubbles in the case of direct melting.The sample is usually treated by preoxidation before fusion sample preparation.In this study,fusion sample preparation was conducted under the following conditions:the Li_(2)B4O_(7)-LiBO_(2)(mass ratio 1∶1)was selected as the mixed flux;the dilution ratio was 20∶1;four drops of 300 g/L LiBr was selected as the release agent;the sample was firstly preoxidized at 800℃for 30 min,and then fused at 1050℃for 19 min.The calibration sample series with proper gradient range were prepared using the certified reference materials of graphite ore,stream sediment,rock and soil.The contents of 10 major and minor components in graphite ores,including Al_(2)O_(3),SiO_(2),Fe_(2)O_(3),MgO,CaO,K_(2)O,Na_(2)O,TiO_(2),MnO and P,were determined by X-ray fluorescence spectrometry(XRF).Ten major and minor components in certified reference materials of graphite ore(GBW03118 and GBW03120)were determined according to the experimental method.The relative standard deviations(RSD)of the determination results were between 0.20%and 3.7%.The measured results were consistent with the certified values.The graphite ore sample was also determined according to the experimental method and industrial standard method JC/T 1021.5-2007,and the results were consistent.

关 键 词：石墨矿 熔融制样 X射线荧光光谱法(XRF) 预氧化 

分 类 号：O657.34[理学—分析化学] TF03[理学—化学]