高分辨连续光源石墨炉原子吸收光谱法测定低铁石英砂中铁  

Determination of iron in low-iron quartz sand by high resolution continuum source graphite furnace atomic absorption spectrometry

作　　者：张丽萍 姚明星[1,2,3] 张宏丽 肖芳[1,2,3] 倪文山 ZHANG Liping;YAO Mingxing;ZHANG Hongli;XIAO Fang;NI Wenshan(Zhengzhou Institute of Multipurpose Utilization of Mineral Resources,CAGS,Zhengzhou 450006,China;National Engineering Research Center for Comprehensive Utilization of Non-Metallic Mineral Resources,Zhengzhou 450006,China;Key Laboratory for Polymetallic Ore Evaluation and Utilization,MNR,Zhengzhou 450006,China)

机构地区：[1]中国地质科学院郑州矿产综合利用研究所,河南郑州450006 [2]国家非金属矿资源综合利用工程技术研究中心,河南郑州450006 [3]自然资源部多金属矿综合利用评价重点实验室,河南郑州450006

出　　处：《冶金分析》2022年第3期1-6,共6页Metallurgical Analysis

基　　金：国家自然科学基金青年基金(21806149);中国地质调查局地质调查工作(DD20190186)。

摘　　要：低铁石英资源创新应用技术的发展需要对影响其品质的关键性铁元素含量进行准确的测定。采用15 mL氢氟酸和2 mL硝酸预先于150℃浸泡2 h,再加入2 mL高氯酸于180℃进行敞开酸消解,最后用1 mL硝酸和1 mL水进行提取。选择248.327 nm波长,采用高分辨连续光源石墨炉原子吸收光谱仪对样品溶液中铁含量进行测定,建立了低铁石英砂中痕量杂质铁的测定方法。对溶样方法、石墨炉升温程序、原子化读数时间、有效像素点等进行了条件优化。结果表明,在20~100 ng/mL的铁质量浓度范围内,以最小二乘法拟合吸光度与质量浓度的校准曲线方程,决定系数达0.999 8,方法检出限为0.002 49μg/g,定量限为0.007 47μg/g。采用实验方法测定8个低铁石英砂样品中的杂质铁含量,结果与电感耦合等离子体质谱法基本一致,5次平行测定的相对标准偏差(RSD)介于2.2%至4.8%之间,加入铁标准溶液进行加标回收试验的回收率在90%~110%之间,满足国家地质矿产行业标准DZ/T 0130—2006对回收率的要求。The development of innovative application technology of low-iron quartz resources required the accurate determination of iron content which was the key element affecting its quality.The sample was presoaked in 15 mL of hydrofluoric acid and 2 mL of nitric acid at 150 ℃ for 2 hours.Then 2 mL of perchloric acid was added for open acid digestion at 180 ℃.Finally,the extraction was conducted with 1 mL of nitric acid and 1 mL of water.The content of iron in the sample solution was determined by high resolution continuum source graphite furnace atomic absorption spectrometer at 248.327 nm.A method for determination of trace impurity iron in low-iron quartz sand was established.The experimental conditions including sample dissolution method,temperature program of graphite furnace,atomization reading time and effective pixels were optimized.The results showed that when the mass concentration of iron was in range of 20-100 ng/mL,the determination coefficient of the calibration curve equation between absorbance and mass fraction fitted by the least square method was up to 0.999 8.The limit of detection of method was 0.002 49 μg/g,and the limit of quantification was 0.007 47 μg/g.The content of impurity iron in eight low-iron quartz samples was determined according to the experimental method.The results were basically consistent with those obtained by inductively coupled plasma mass spectrometry.The relative standard deviation(RSD,n=5) of determination results were between 2.2% and 4.8%.The standard solution of iron was added for recovery tests.The recoveries were between 90% and 110%,which could meet the requirements of recovery in the national geological and mineral industry standard of DZ/T0130-2006.

关 键 词：高分辨连续光源 石墨炉原子吸收光谱法 低铁石英砂 铁 

分 类 号：O657.31[理学—分析化学] TF031[理学—化学]