密闭消解—电感耦合等离子体光谱法测定稀有金属矿选冶流程样品中锂、铍、铌和钽.pdf

密闭消解电感耦合等离子体光谱法测定稀有金属矿选冶流程样品中锂、铍、铌和钽雷勇，勾钰霞，易建春，赵朝辉，潘刚，余滔（中国地质科学院矿产综合利用研究所，自然资源部战略性矿产综合利用工程技术创新中心，四川成都610041）摘要：这是一篇矿物分析领域的论文。采用盐酸、硝酸、氢氟酸、硫酸于聚四氟乙烯密闭消解罐中加热消解，酒石酸稀盐酸介质提取，以电感耦合等离子体光谱法同时测定溶液中锂、铍、铌和钽。Li 和 Be 在050 g/mL、Nb2O5和 Ta2O5在 0100 g/mL 范围内呈良好测现性关系，校准曲线相关系数 r 均大于 0.9999，方法检出限分别为 0.1 g/g、0.5 g/g、1.0 g/g、0.1 g/g。用于实际样品分析，加标回收率为 94.6%105.6%，锂、铍、铌、钽的相对标准偏差（n=11）分别为 1.08%7.04%、0.65%13.06%、2.597.32%、2.02%7.60%，用标准样品分析，测定值与认定值相符。关键词：矿物分析；密闭消解；酒石酸；锂；铍；铌；钽；电感耦合等离子体原子发射光谱法doi:10.3969/j.issn.1000-6532.2023.04.032中图分类号:TD982;P575 文献标志码:A 文章编号:1000-6532（2023）04020506 锂、铍、铌、钽作为稀有金属矿中的主要回收元素，在工业中用途广泛，是现代尖端电子、新能源、航空航天、医疗和军事装备等工业中不可缺少的重要金属原料，随着高品位矿物几十年来的开发，其资源已日益枯竭，而社会资源量需求却在急剧增加，国家也提出了高质量发展的要求，稀有金属矿的勘探、综合利用开发也越来越受到重视1-4。因此建立稀有金属矿原矿及选冶流程样品精矿、中矿、尾矿的快速准确测试方法是稀有金属矿的勘探、综合利用开发的一个非常重要的环节。目前介绍这四种元素的分析方法报道比较多，但是由于稀有金属中各元素的矿物十分复杂，很难用一种方法同时快速准确的分析出这4 种元素。高丹等5采用微波消解电感耦合等离子体原子发射光谱法测定矿石样品中的铍；杨萍等6采用 ICP-AES 法测定矿石中的 BeO；潘钢7等采用电感耦合等离子体原子发射光谱法测定矿石样品中铌钽；韩晓等8采用电感耦合等离子体原子发射光谱法测定矿石样品中锂，姚玉玲等9采用树脂交换分离电感耦合等离子质谱法测定锡矿石的铌钽。这些方法同时只能检测一两个元素，不能满足四种元素同时检测的需求。赵学沛等采用 ICP-AES 测定稀有金属矿中锂铍铌钽锡10，胡兰基等采用电感耦合等离子体质谱法测定花岗伟晶岩中锂、铍、铷、铯、铌和钽11，这些方法虽能同时检测四种元素，但方法未对选冶流程样品中精矿、中矿、尾矿进行研究。本文研究对象为川西和新疆地区的稀有金属矿，通过前处理方式研究，国家标准物质验证有效性，建立了一种可以同时快速准确的分析出锂、铍、铌和钽 4 种元素并满足样品基体复杂、含量范围变化大的方法。1实验部分 1.1主要仪器及工作条件Avio-500 型电感耦合等离子体原子发射光谱仪。工作条件：RF 功率1300 W；冷却气 12.0 L/min；雾化气流量 0.7 L/min；辅助气流量 0.2 L/min。进 收稿日期:2023-05-04作者简介:雷勇（1982-），男，工程师，主要从事分析方法研究。第 4 期矿产综合利用2023 年 8 月Multipurpose Utilization of Mineral Resources 205 样量 1.5 L/min，观测高度 15 mm，观测方式根据含量选择轴向或镜像，积分时间 5 s。分析谱线：Li:670.784 nm、Be:234.861 nm、Nb:292.781 nm、Ta:240.063 nm。1.2标准溶液和主要试剂锂、铍、铌、钽标准储备溶液均为 1000 mg/L；用 1%酒石酸-0.5%盐酸逐级稀释，配制成 100 mL混合标准溶液（表 1）。所用试剂除特别标明外均为分析纯，水为去离子水。表 1 标准溶液中锂、铍、铌、钽元素浓度Table 1 Concentrations of Li、Be、Nb and Ta in thestandard solutions标准溶液编号含量/（g/mL）LiBeNb2O5Ta2O51000020.50.50.50.531111455555101010106505050507100100 1.3实验方法根据分析元素含量称取 0.1000 g 0.5000 g（精确至 0.1 mg）已于 105 烘干的样品，置于聚四氟乙烯密闭消解罐中，加入 4 mL 盐酸、3 mL 硝酸、4 mL 氢氟酸、1 mL 硫酸，密闭，于加热板上加热到 260 后继续消解 4 小时，取下冷却，取下密封盖，于加热板上加热至冒硫酸白烟，10 mL 100 g/L 酒石酸-5%盐酸溶液加热提取，冷却定容 100 mL，摇匀静置待测。随同样品制作两份空白溶液。按仪器条件用 ICP-AES 光谱仪测定锂、铍、铌、钽，绘制标准曲线，根据回归方程计算样品试液浓度。2结果与讨论 2.1分析的干扰及校正ICP-AES 存在光谱干扰和非光谱干扰两类干扰。非光谱干扰即基体效应，虽然采用酸溶消解基体干扰较小，但酒石酸加入过多会造成严重的基体干扰，本文选择酒石酸-盐酸为提取液，即保证样品完全被提取又不至于引入过多的基体对仪器测定稳定性造成影响。而光谱干扰主要是背景干扰和谱线干扰。实验中通常采用标准溶液与试样溶液中基体物质、酸度保一致来降低基体效应，通过选择合适的分析谱线来降低谱线干扰。实验对仪器推荐的锂、铍、铌、钽、锡分析线进扫描，比较同一元素几条分析线特点，同时考虑共存元素的相互干扰问题，从中选择灵敏度高、背境低、基体对测定不干扰或者干扰尽量小的谱线为分析线，选定锂、铍、铌、钽的较佳分析线分别为 Li：670.784 nm、Be：234.861 nm、Nb：292.781 nm、Ta：240.063 nm。2.2溶样方式的选择样品中锂属于易溶碱金属元素，常规酸溶可完全消解；铌、钽一般采用酸溶即可，如样品中含有锆英石、锡石、钽铝石、绿柱石等成分常规酸溶消解不完全，需采用碱熔融法；铍主要为硅酸盐类矿物存在，其分解比一般硅酸盐困难，特别对于含有金绿宝石和黄玉等具有很强的化学稳定性矿物时，常规酸溶消解不完全，一般采用碱熔融法。由于铌、钽易水解的性质，提取样品时必须加入一定量的络合剂（酒石酸），否则容易形成土酸析出。在测定溶液中已加入一定的基体（酒石酸）情况下，再碱熔引入了更多的离子基体，仪器测定时必须大比例稀释，结果是空白高、检出限低、增加测量误差，不适用于低含量样品的检测，如尾矿、中矿。本文选择研究酸溶方式消解样品。本文选取选冶流程样品 A1A4，研究了 a：盐酸+氢氟酸+硝酸+高氯酸敞口消解、b：盐酸+氢氟酸+硝酸+硫酸敞口消解、c：盐酸+氢氟酸+硝酸+高氯酸密闭消解、d：盐酸+氢氟酸+硝酸+硫酸密闭消解四种消解方式，原始数据见表 2。由表 2可知，锂元素采用 a、b、c、d 四种消解方式结果一致；铌、钽元素采用 c、d 消解方式比采用 a、b 消解方式更优；铍元素 4 种消解方式结果都不一致，采用 d 消解方式较优。本文选择 d：盐酸+氢氟酸+硝酸+硫酸密闭消解方式消解样品。2.3溶液介质的选择ICP-AES 分析常用的介质为 2%3%硝酸。而铌、钽在酸性溶液中不稳定，易于水解生成“土酸”沉淀。所以在提取铌钽时需加入络合剂防止水解现象发生，络合剂与铌钽形成稳定的络合离子存在于溶液中。我们采用国家一级标准样品GBWO7185 做络合剂用量实验（Nb2O5含量为0.52%、Ta2O5含量为 1.02%）。最后保证在制备 206 矿产综合利用2023 年的溶液中酒石酸的量为 0、0.25%、0.5%、0.75%、1.0%、1.5%、2.0%、2.5%、3.0%、4.0%、5.0%、6.0%，用 ICP-AES 测定铌、钽以确定较佳酒石酸浓度。结果见图 1。表 2 不同样品消解方法测定比较/%Table 2 Comparision of determination results by different digestion method样品元素a常压高氯酸冒烟b常压硫酸冒烟Li2OBeONb2O5Ta2O5Li2OBeONb2O5Ta2O5样品15.490.180.07480.03235.470.220.07270.0291样品20.140.00380.00260.00120.150.00440.00270.0011样品31.370.04250.00230.00081.340.04950.00270.0009样品45.340.220.00340.00245.260.290.00360.0031样品元素c密闭高氯酸冒烟d密闭硫酸冒烟Li2OBeONb2O5Ta2O5Li2OBeONb2O5Ta2O5样品15.480.230.08090.04125.490.250.08110.0391样品20.140.00580.00220.00130.140.00620.00200.0012样品31.320.06680.00230.00081.330.06910.00310.0010样品45.310.350.00360.00255.230.390.00370.0033 2040608010012001234567Ta2O5 回收率Nb2O5 回收率回收率/%图 1 酒石酸浓度Fig.1 Tartaric acid concentration 由图可知，酒石酸的浓度对样品中铌、钽的提取影响较大，对钽的影响大于对铌的影响，当溶液中酒石酸达到 1%及以上时，铌钽的提取率都达到 100%，为保证其完全被提取，又不至于引入过多的基体对仪器测定稳定性造成影响。选定酒石酸的浓度为 1%。在实际实验测试工作中，发现加入过多的酒石酸对仪器测定的稳定性有严重干扰。结合赵学沛等在 ICP-AES 测定稀有金属矿中锂铍铌钽锡10中做的研究，本文采取 10 mL 100(g/L)酒石酸-5%盐酸为提取介质。2.4方法检出限方法检出限作为分析方法分析质量重要的技术指标，与所用仪器的灵敏度、精密度和仪器检出限有关外，还与测定溶液的空白值和方法的总稀释倍数有关。在仪器较佳化的条件下，按 1.3 实验方法连续测定 11 份样品空白溶液，以所得结果3 倍标准偏差计算得到锂、铍、铌、钽的检出限分别为：0.1 g/g、0.5 g/g、1.0 g/g、0.1 g/g。2.5加标回收率取选冶流程样品 A1A4，加入一定量的锂、铍、铌、钽标准溶液，按 1.3 实验方法进行样品消解测定并计算回收率见表 3。表 3 加标回收（n=3）Table 3 Standerd addition recovery（n=3）样品Li2OBeO样品含量/%加入量/%测定平均值/%回收率/%样品含量/%加入量/%测定平均值/%回收率/%A15.49510.3096.20.250.250.4998.3A20.14410.10.2421980.00620.010.0168105.6A31.3312.34101.30.06910.10.1712102.1A45.23510.1297.70.390.50.8897.66样品Nb2O5Ta2O5样品含量/%加入量/%测定平均值/%回收率/%样品含量/%加入量/%测定平均值/%回收率/%A10.08110.10.180299.10.03910.050.0901101.9A20.00200.00250.004494.680.00120.0010.002296.4A30.00310.00250.005596.20.0010.0010.002095.2A40.00370.00250.0062101.90.00330.0050.008297.7第 4 期2023 年 8 月雷 勇等：密闭消解电感耦合等离子体光谱法测定稀有金属矿选冶流程样品中锂、铍、铌和钽 207 从表 3 可以看出，样品加标回收率在 94.68%105.6%之间，可满足稀有金属矿中锂、铍、铌、钽、元素的测定要求。2.6方法精密度和准确度选取含有不同含量锂、铍、铌、钽元素的国家标准物质 GBW07183、GBW07184、GBW07185、GBW07152、GBW07154，按 1.3 实验方法进行 11次平行实验，结果见表 4。由表 4 可以看出，该方法对标准物质的测定值与认定值基本一致，含量大于一百克吨时标准偏差都在 7.76%以下，含量小于一百克吨时标准偏差都在 12.72%以下，说明该方法适用于稀有金 表 4 方法的精密度和准确度Table 4 Precision and the accuracy of the method标准物质编号Li2OBeONb2O5Ta2O5GBW07152-10.460.0180.00310.0040GBW07152-20.460.0170.00300.0044GBW07152-30.440.0180.00280.0050GBW07152-40.450.0190.00330.0047GBW07152-50.440.020.00290.0048GBW07152-60.470.0170.00310.0050GBW07152-70.450.0180.00270.0051GBW07152-80.460.0190.00320.0045GBW07152-90.460.0180.00280.0047GBW07152-100.460.0170.00300.0051GBW07152-110.440.0170.00260.0046测定平均值/%0.450.0180.00300.0047认定值/%0.460.0180.00270.0049RSD/%2.285.567.217.17标准物质编号Li2OBeONb2O5Ta2O5GBW07154-10.780.0320.00460.0083GBW07154-20.790.0340.00480.0081GBW07154-30.810.0330.00520.0086GBW07154-40.760.0330.00460.0094GBW07154-50.780.0320.00500.0086GBW07154-60.790.0340.00480.0088GBW07154-70.770.0310.00440.0089GBW07154-80.800.0300.00460.0085GBW07154-90.780.0330.00490.0084GBW07154-100.770.0360.00430.0082GBW07154-110.790.0350.00510.0085测定平均值/%0.780.0330.00480.0086认定值/%0.790.0330.00420.0089RSD/%1.845.255.924.23标准物质编号Li2OBeONb2O5Ta2O5GBW07183-13.00GBW07183-23.01GBW07183-33.00GBW07183-43.02标准物质编号Li2OBeONb2O5Ta2O5GBW07183-52.99GBW07183-62.98GBW07183-73.01GBW07183-83.03GBW07183-93.02GBW07183-103.00GBW07183-113.05测定平均值/%3.01认定值/%未给定3.02未给定未给定RSD/%0.65标准物质编号Li2OBeONb2O5Ta2O5GBW07184-13.860.0180.00880.013GBW07184-23.800.0180.00820.013GBW07184-33.830.0160.00860.014GBW07184-43.920.0170.00930.013GBW07184-53.860.0190.00860.012GBW07184-63.880.0170.00830.014GBW07184-73.890.0180.00890.014GBW07184-83.800.0160.00850.012GBW07184-93.830.0170.00840.015GBW07184-103.910.0190.0080.012GBW07184-113.890.0160.00850.014测定平均值/%3.860.0170.0090.013认定值/%3.890.0160.00810.013RSD/%1.086.593.967.76标准物质编号Li2OBeONb2O5Ta2O5GBW07185-10.0110.00200.531.01GBW07185-20.0120.00180.501.03GBW07185-30.0120.00160.520.99GBW07185-40.0110.00130.491.02GBW07185-50.0110.00170.501.01GBW07185-60.0100.00190.510.98GBW07185-70.0100.00180.511.05GBW07185-80.0120.00170.531.03GBW07185-90.0110.00140.521.04GBW07185-100.0100.00150.501.02GBW07185-110.0110.00150.521.01测定平均值/%0.0110.00170.511.02认定值/%0.0110.00120.521.02RSD/%7.0412.722.602.01 208 矿产综合利用2023 年属矿样品中锂、铍、铌、钽元素的测定。3结论本文建立了盐酸、硝酸、氢氟酸、硫酸于聚四氟乙烯密闭消解罐中加热消解样品，酒石酸稀盐酸介质提取，以电感耦合等离子体光谱法同时测定稀有金属矿选冶流程样品中锂、铍、铌、钽含量方法，该方法灵敏度高、精密度好、测定含量范围广、能满足稀有金属矿精矿、中矿、尾矿、原矿的测定需求。参考文献:1 吴西顺,王登红,黄文斌,等.全球锂矿及伴生铍铌钽的采选冶技术发展趋势J.矿产综合利用,2019(1):1-6.WU X S,WANG D H,HUANG W B,et al.Global technicaldevelopment trends of litihium minerals and associatedberyllium-niobium-tantalum exploitationJ.MultipurposeUtilization of Mineral Resources,2019(1):1-6.2 徐正震,梁精龙,李慧,等.含锂资源中锂的提取研究现状及展望J.矿产综合利用,2021(5):32-37.XU Z Z,LIANG J L,LI H,et al.Research status and prospectsof lithium extraction from lithium containing resourcesJ.Multipurpose Utilization of Mineral Resources,2021(5):32-37.3 李成秀,程仁举,刘星.我国锂辉石选矿技术研究现状及展望J.矿产综合利用,2021(5):1-8.LI C X,CHENG R J,LIU X.Research status and prospects ofspodumene ore beneficiation technology in ChinaJ.Multipurpose Utilization of Mineral Resources,2021(5):1-8.4 何飞,高利坤,饶兵,等.从锂云母中提锂及综合利用的研究进展J.矿产综合利用,2022(5):82-89.HE F,GAO L K,RAO B,et al.Research progress on lithiumextraction and 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Journal of InorganicAnalytical Chemistry,2021,11(2):36-39.9 姚玉玲,赵朝辉,刘淑君.树脂交换分离电感耦合等离子 质 谱 法 测 定 锡 矿 石 的 铌 钽 J.矿 产 综 合 利 用,2021(5):146-151.YAO Y L,ZHAO C H,LIU S J.Determination of niobium andtantalum in tin ore by inductively coupled plasma massspectrometry with resin exchange separationJ.MultipurposeUtilization of Mineral Resources,2021(5):146-151.10 赵学沛.多种酸溶矿 ICP-AES 测定稀有金属矿中锂铍铌钽锡J.化学研究与应用,2017,29(11):1714-1718.ZHAO X P.Determination of lithium,beryllium,niobium andtantalum in rare matal ores by four acid soluble ICP-AESJ.Chemical Research and Application,2017,29(11):1714-1718.11 胡兰基,朱琳,赵玉卿,等.电感耦合等离子体质谱法测定花岗伟晶岩中锂、铍、铷、铯、铌和钽J.化工矿产地质,2020,42(4):348-351.HU L J,ZHU L,ZHAO Y Q,et al.Determination of Li、Be、Rb、Cs、Nb and Ta in granite-pegmatite by inductivelycoupled plasma mass spectrometricJ.Geology of ChemicalMinerals,2020,42(4):348-351.Inductively Coupled Plasma Atomic Emission SpectrometricDetermination of Lithium、Beryllium、Niobium and Tantalum in Sample第 4 期2023 年 8 月雷 勇等：密闭消解电感耦合等离子体光谱法测定稀有金属矿选冶流程样品中锂、铍、铌和钽 209 of Beneficiation Process of Rare Metal Ore after Closed DigestionLei Yong,Gou Yuxia,Yi Jianchun,Zhao Chaohui,Pan Gang,Yu Tao(Institute of Multipurpose Utilization of Mineral Resources,Technology Innovation Center forComprehensive Utilization of Strategic Minerals Resources,Ministry of Natural Resources,Chengdu,Sichuan,China)Abstract:This is an essay in the field of mineral analysis.The ore sample was digested with Hydrochloricacid、nitric acid、hydrofluoric acid、sulfuric acid in a closed polytetrafluoroethylene digestion tank.Hydrochloric acid and tartaric acid medium is used for extraction.The Lithium、Beryllium、niobium andtantalum in the prepared solution were determined by inductively coupled plasma atomic emissionspectrometry(ICP-AES).The emission spectral intensity of Lithium、Beryllium、niobium and tantalumshowed a good linear relationship with(Li)and(Be)in the range of 0 50 g/mL、(Nb2O5)and(Ta2O5)in the range of 0100 g/mL.The correlation coefficients of the calibration curve for Lithium、Beryllium、niobium and tantalum were both 0.9999 The detection limits for Lithium、Beryllium、niobium and tantalum were 0.1 g/g、0.5 g/g、1.0 g/g、0.1 g/g,respectivelyThe proposed methodwas applied to the determination of the actual sample giving recovery rate of 94.6%105.6%and therelative standard deviations (RSD n=11)of Lithium、Beryllium、niobium and tantalum are1.08%7.04%、0.65%13.06%、2.597.32%、2.02%7.60%,respectivelyThis method was appliedto the analysis of the standard sample and the results were consistent with the certified valuesKeywords:Mineral analysis;Closed digestion;Tartaric acid;Lithium;Beryllium;Niobium;Tantalum;Inductively coupled plasma atomic emission spectrometry (上接第 204 页)Process Mineralogy of a Titanomagnetite in South YunnanLiu Feiyan1,Xie Zhiyuan2,Deng Bing1,Zhang Yuan1,Liu Yingdong1,Zhou Jiayun1(1.Institute of Multipurpose Utilization of Mineral Resources,CAGS,Chengdu,Sichuan,China;2.SichuanGeological and Mineral Resources Group Co.,Ltd,Chengdu,Sichuan,China)Abstract:This is an essay in the field of process mineralogy.A titanium magnetite ore in Yunnan not onlyhas high iron and titanium,but also is associated with scandium.In order to realize the comprehensiveutilization of the ore,the process mineralogy of the ore was studied.The chemical composition of the orewas identified by means of X-ray fluorescence spectroscopy and chemical analysis;The technologicalcharacteristics of the minerals were studied by means of X-ray diffraction (XRD),scanning electronmicroscopy and energy dispersive analysis (SEM-EDS),electron probe microanalysis (EPMA),and theoccurrence state of scandium was emphatically investigated.The results show that the main carrier mineralsof iron in ore are titanomagnetite and amphibole,followed by ilmenite;The carrier mineral of titanium ismainly ilmenite,with a small amount occurring in sphene;Scandium is mainly distributed in amphibole.Theresults of elemental distribution show that the theoretical grades of iron,titanium and scandium are 71.02%,47.40%and 96.63 g/t respectively,and the theoretical recoveries are 40.52%,66.48%and 97%respectively.The mineralogical factors affecting the recovery index of mineral processing are analyzed,which provides atheoretical support for the subsequent beneficiation and smelting process.Keywords:Process mineralogy;Titanomagnetite;Occurrence status;Scandium;Comprehensive utilization 210 矿产综合利用2023 年