摘要
磷矿石中的稀土元素测定方法主要使用电感耦合等离子体质谱法(ICP-MS),样品处理方式主要采用敞口混合酸溶和碱熔。传统的酸溶和碱熔处理矿石样品时间较长,试剂加入量大,操作过程较为繁琐,且易造成环境污染。微波消解直接向样品释放能量,工作效率高,且易挥发元素被保留在消化溶液中,防止挥发造成结果偏差及环境污染。本文采用微波消解对磷矿石进行处理,并在二次消解过程中加入饱和硼酸络合溶矿过程中产生的不溶物氟化钙,在线加入铑和铼双内标的方式,建立了ICP-MS测定磷矿石中15种稀土元素的方法。结果表明:二次消解过程中加入饱和硼酸能有效地络合沉淀,彻底溶解样品,经上机测定后15种稀土元素的相对标准偏差(RSD)在0.68%~4.52%之间,回收率在93.1%~106.6%之间,方法检出限为0.003~0.029μg/g。选取两个磷矿石样品,用本方法与混合酸(盐酸-硝酸-氢氟酸-硫酸)酸溶方法进行对比试验,相对标准偏差在-5.82%~5.99%之间,表明本方法测定稀土元素是有效可行的。对于样品的前处理方法,酸溶、碱熔和微波消解都有各自的特点,微波密封消解能避免一些能形成易挥发组分的损失并且外源性污染少。本方法拓展了测定磷矿石中稀土元素的样品前处理方法,操作性强,是对现行方法的有益补充。
It takes a long time to treat ore samples by traditional alkali fusion and acid dissolution,and it is easy to cause environmental pollution.Microwave digestion directly releases energy to the sample with high efficiency,and volatile elements are retained in the digestion solution to prevent volatilization from causing deviation of results and environmental pollution.In this experiment,0.2g of phosphate rock sample was taken and placed in a microwave digestion tank.3mL hydrochloric acid,3mL nitric acid,and 2mL hydrofluoric acid were added and then dissolved in the microwave digestion instrument.Then,2mL of saturated boric acid solution was added for a further microwave digestion.After cooling,the sample was diluted in a 100mL volumetric flask with deionized water.Online addition of rhodium and rhenium as dual internal standards for inductively coupled plasma-mass spectrometry(ICP-MS)determination of rare earth elements in phosphate rock was performed.The relative standard deviation(RSD)of 15 rare earth elements was between 0.68%and 4.52%,the recovery was between 93.1%and 106.6%,and detection limit was between 0.003-0.029μg/g.Two phosphate ore samples were selected and compared with the mixed acid dissolution method.The relative standard deviation was-5.82%-5.99%.
作者
张楠
郑智慷
王家松
曾江萍
ZHANG Nan;ZHENG Zhikang;WANG Jiasong;ZENG Jiangping(Tianjin Center,China Geological Survey,Tianjin 300170,China;North China Geological Science and Technology Innovation Center,Tianjin 300170,China;Key Laboratory of Coast Geo-Environment,China Geological Survey,Tianjin 300170,China)
出处
《岩矿测试》
CAS
CSCD
北大核心
2024年第2期366-374,共9页
Rock and Mineral Analysis
基金
中国地质调查局地质调查项目“地质矿产调查标准化与标准制修订(中国地质调查局天津地质调查中心)”(DD20230272)。
关键词
磷矿石
稀土元素
微波消解
饱和硼酸
络合
电感耦合等离子体质谱法
phosphate ore
rare earth elements
microwave digestion
saturated boric acid
complexation
inductively coupled plasma-mass spectrometry
