微波消解-电感耦合等离子体原子发射光谱法测定铁矿石中硫化铁  

Determination of iron sulfide in iron ore by inductively coupled plasma atomic emission spectrometry with microwave digestion

作　　者：郑智慷 乔赵育 王家松 张楠[1,2] 曾江萍 王力强 ZHENG Zhi-kang;QIAO Zhao-yu;WANG Jia-song;ZHANG Nan;ZENG Jiang-ping;WANG Li-qiang(Tianjin Center,China Geological Survey,Tianjin 300170,China;North China Center for Geoscience Innovation,Tianjin 300170,China;China Inspection(Tianjin)Testing Co.,Ltd.,Tianjin 300300,China;Key Laboratory of Geological Environment of Muddy Coastal Zone,China Geological Survey,Tianjin 300170,China)

机构地区：[1]中国地质调查局天津地质调查中心,天津300170 [2]华北地质科技创新中心,天津300170 [3]中检(天津)检测有限公司,天津300300 [4]中国地质调查局泥质海岸带地质环境重点实验室,天津300170

出　　处：《冶金分析》2020年第3期37-43,共7页Metallurgical Analysis

摘　　要：准确测定铁矿石中硫化铁对于铁矿石的物相分析具有重要意义。目前,铁矿石中硫化铁的前处理方法以系统分析法为主,虽然该方法发展较为成熟,但是存在着步骤繁琐、分离不彻底、硫化铁易损失等问题,易导致测定结果不准确。通过不同溶样方法的对比试验,确定了采用饱和溴水-高锰酸钾混合溶液直接浸取铁矿石的方法以充分浸取硫化铁;通过不同定容方式的对比试验,选择氟化铵-盐酸混合溶液作为提取介质,以最大程度抑制铁的水解,经电感耦合等离子体原子发射光谱法(ICP-AES)测定,得到铁矿石中硫化铁(以铁计,下同)的含量。方法中校准曲线的线性相关系数为0.9999;硫化铁的检出限为3μg/g。按照实验方法测定铁矿石物相成分分析标准物质中硫化铁,结果的相对标准偏差(RSD,n=8)为1.9%~3.5%,相对误差为1.3%~2.5%。实验方法用于测定3个铁矿石实际样品中硫化铁,结果的RSD(n=5)为0.68%~3.0%。方法适用于铁矿石中0.04%~8%(质量分数)硫化铁的测定。The accurate determination of iron sulfide in iron ore has great significance on the phase analysis of iron ore.At present,the system analysis method was usually used for the pretreatment of iron sulfide in iron ore.Although this method was relatively mature,there were still some problems such as complicated procedures,incomplete separation and easy loss of iron sulfide components,which easily caused inaccurate determination results.The comparative experiments of various sample dissolution methods were conducted.The mixed solution of saturated bromine water and potassium permanganate was selected for the direct leaching iron ore to completely leach iron sulfide.Moreover,the comparative experiments of various dilution methods were conducted,and the mixture of ammonium fluoride and hydrochloric acid was adopted for the leaching medium to inhibit the hydrolysis of iron to the full extent.Then the content of iron sulfide(in term of iron content,the same below)in iron ore was determined by inductively coupled plasma atomic emission spectrometry(ICP-AES).The linear correlation coefficient of calibration curve was 0.9999.The limit of detection for iron sulfide was 3μg/g.The proposed method was used to determine the content of iron sulfide in certified reference materials for phase composition analysis of iron ore.The relative standard deviation(RSD,n=8)of determination results were between 1.9%and 3.5%,and the relative errors were between 1.3%and 2.5%.The contents of iron sulfide in three iron ore actual samples were determined according to the proposed method,and RSDs(n=5)were between 0.68%and 3.0%.The proposed method was applicable for the determination of in iron sulfide(0.04%-8%)in iron ore.

关 键 词：微波消解 电感耦合等离子体原子发射光谱法(ICP-AES) 铁矿石 硫化铁 铁 

分 类 号：O657.31[理学—分析化学]