Determination of calcium fluoride in dolomite-bearing fluorite by inductively coupled plasma atomic emission spectrometry combined with fluoride ion selective electrode method
FENG Zhenhua1,2, KUAI Lijun1,2, SHAO Huiqi3,4
1. BGRIMM MTC Technology Technical Co.,Ltd.,Beijing 102628,China; 2. Beijing Key Lab of Mineral Resources Evaluation and Analysis,Beijing 102628,China; 3. National Museum of China,Beijing 100006,China; 4. Key Scientific Research Base of Metal Conservation (National Museum of China),State Administration for Cultural Heritage,Beijing 100006,China
Abstract：Dolomite-bearing fluorite contains dolomite and calcium silicate. The existing test methods are greatly affected by the fluorite types and the experimental conditions. It is difficult to avoid the interference of dolomite, calcium silicate, and other components, which leads to higher determination results of calcium fluoride. In this paper, the content distributions of dolomite and calcium silicate in primary filtrate and secondary filtrate were analyzed by respective determination of magnesium and silicon in primary filtrate, secondary filtrate and sample. Then the determination process was optimized combined with fluorine content in primary filtrate. Dolomite-bearing fluorite was dissolved with 10% acetic acid, and calcium fluoride in primary residue was extracted with aluminum trichloride solution. The content of fluorine in primary filtrate was determined by fluoride ion selective electrode method, and the content of calcium in secondary filtrate was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The results of the two methods were converted into calcium fluoride content and then added together. Consequently, a method for determination of low-grade calcium fluoride in dolomite-bearing fluorite was established by ICP-AES combined with fluoride ion selective electrode. The effect of aluminum trichloride matrix on the determination of calcium in range of 10.00-40.00 μg/mL was investigated. The results showed that aluminum trichloride matrix had great matrix effect on the determination of calcium. Therefore, the standard solution series were prepared by matrix matching method. The contents of calcium fluoride in dolomite-bearing fluorite samples were determined according to the proposed method, and the relative standard deviations (RSD, n=7) of determination results were between 0.21% and 0.64%. The recoveries were between 99.2% and 100.3%. The proposed method could eliminate the interference of dolomite and calcium silicate in dolomite-bearing fluorite on determination results of calcium fluoride.
[1] 徐鼎,吕晶,刘倩,等.中国萤石资源进出口贸易现状特征分析及建议[J].现代矿业,2019,35(10):12-15. XU Ding,LÜ Jing,LIU Qian,et al.Analysis and suggestions on current situation and characteristics of import and export trade of fluorite resources in China[J].Modern Mining,2019,35(10):12-15. [2] 陈石义,张寿庭.我国氟化工产业中萤石资源利用现状与产业发展对策[J].资源与产业,2013,15(2):79-83. CHEN Shiyi,ZHANG Shouting.Approaches to use and development of calcium fluoride in China′s fluoride chemical industry[J].Resources ＆ Industries,2013,15(2):79-83. [3] 张越.EDTA滴定法测定萤石中氟化钙含量的方法改进[J].中国无机分析化学,2019,9(4):36-39. ZHANG Yue.An improved method for determination of calcium fluoride in fluoride by EDTA titration[J].Chinese Journal of Inorganic Analytical Chemistry,2019,9(4):36-39. [4] 曾洪波.碱性条件下EDTA络合滴定法测定萤石中的氟化钙及碳酸钙含量[J].世界有色金属,2016(6):53-54. ZENG Hongbo.Determination of calcium fluoride and calcium carbonate of the fluorite concentrate samples by EDTA complexing titration[J].World Nonferrous Metals,2016(6):53-54. [5] 罗素华.盐酸-硼酸分解-EDTA容量法快速测定萤石中的氟化钙[J].铜业工程,2003(3):37-38. LUO Suhua.Quick determination of calcium fluoride in fluorite[J].Copper Engineering,2003(3):37-38. [6] 钟平.赣南萤石中CaF2含量的EDTA快速测定[J].江西化工,2006(3):102-103. ZHONG Ping.The method of speed mensuration with EDTA of the content of calcium fluoride in Gannan′s fluoride[J].Jiangxi Chemical Industry,2006(3):102-103. [7] 马熠罡,高翔宇,张尼,等.高含量碳酸钙基体中氟化钙的准确测定[J].化学分析计量,2019,28(4):91-93. MA Yigang,GAO Xiangyu,ZHANG Ni,et al.Accurate determination of calcium fluoride in high calcium carbonate matrix[J].Chemical Analysis and Meterage,2019,28(4):91-93. [8] 蒋政,罗旻延,李玲,等.碱熔-离子选择性电极法测定萤石中氟化钙[J].冶金分析,2021,41(10):91-97. JIANG Zheng,LUO Minyan,LI Ling,et al.Determination of calcium fluoride in fluoride by ion selective electrode method after alkali fusion[J].Metallurgical Analysis,2021,41(10):91-97. [9] 杨珍,孙银生,贺攀红,等.电感耦合等离子体原子发射光谱法快速测定萤石矿中氟化钙[J].冶金分析,2013,33(11):71-73. YANG Zhen,SUN Yinsheng,HE Panhong,et al.Rapid determination of calcium fluoride in fluoride by inductively coupled plasma atomic emission spectrometry[J].Metallurgical Analysis,2013,33(11):71-73. [10] 阿丽莉,吴培源,毛盟,等.钙乙酸分离-三氯化铝浸取-电感耦合等离子体原子发射光谱法测定地质样品中氟化钙[J].冶金分析,2022,42(7):32-38. A Lili,WU Peiyuan,MAO Meng,et al.Determination of calcium fluoride in geological sample by inductively coupled plasma atomic emission spectrometry with acetate separation-aluminum trichloride leaching[J].Metallurgical Analysis,2022,42(7):32-38. [11] 李勇,顾强,刘洪艳.熔融制样-X射线荧光光谱法测定萤石中氟化钙和二氧化硅[J].冶金分析,2022,42(8):29-34. LI Yong,GU Qiang,LIU Hongyan.Determination of calcium fluoride and silicon dioxide in fluoride by X-ray fluorescence spectrometry with fusion sample preparation[J].Metallurgical Analysis,2022,42(8):29-34. [12] 袁永海,杨锋,吴杰,等.含钙乙酸分离-熔融制样-X射线荧光光谱法测定萤石中氟化钙[J].冶金分析,2023,43(3):34-39. YUAN Yonghai,YANG Feng,WU Jie,et al.Determination of calcium fluoride in fluorite by X-ray fluorescence spectrometry with fusion sample preparation after separation by calcium-containing acetic acid[J].Metallurgical Analysis,2023,43(3):34-39. [13] 张霞,张祁,刘浩然.萤石中氟化钙的测定[J].化工矿产地质,2017,39(1):58-60. ZHANG Xia,ZHANG Qi,LIU Haoran.The determination of calcium fluoride in fluorite[J].Geology of Chemical Minerals,2017,39(1):58-60. [14] 中华人民共和国国家质量监督检验检疫总局,中国国家标准化管理委员会.GB/T 5195.16—2017萤石 硅、铝、铁、钾、镁和钛含量的测定 电感耦合等离子体原子发射光谱法[S].北京:中国标准出版社,2017.
