ICP-AES法测定离子吸附型稀土矿镁盐体系稀土浸出液中稀土与非稀土杂质

Determination of Rare Earth Elements and Non-Rare Earth Elements in Leaching Solution with Magnesium Salt System of Ion-Adsorption Type Rare Earth Ore by ICP-AES

硫酸镁作为离子吸附型稀土矿的浸取剂,具有价格便宜、对环境影响小等优点,有望消除硫酸铵浸取过程中的氨氮污染,实现离子吸附型稀土矿的生态友好浸取。离子吸附型稀土矿浸出过程耗时长,过程中稀土浸出液所需取样数量多,而且稀土浸出液具有需要测试元素多,样品中元素含量差异大,样品之间同一元素含量差异大等特点。通过分析谱线选择、基体影响分析、谱峰漂移校正,分段计算等手段,建立了电感耦合等离子体原子发射光谱法(ICP-AES)测定镁盐体系稀土浸出液中稀土与非稀土杂质的方法。通过精密度实验、加标回收实验、空白实验及方法对比实验来验证方法的可靠性。研究表明:所建方法的方法检出限小于0.03 mg·L^(-1),被测元素的测试误差以及相对标准偏差都能控制在5%以内,可以实现对镁盐体系稀土浸出液中稀土、铝、镁、钙等元素的准确测试,获得较真实的稀土浸出率等过程参数,为硫酸镁浸取离子吸附型稀土矿这一新技术提供了分析测试保障。

Magnesium sulfate which had advantages of low price,little influence on environment,etc,was used as leaching agent for the ion-adsorption type rare earths ore. It was expected to solve the problem of ammonia-nitrogen pollution in the ammonium sulfate leaching process,and realize the efficient ecological friendly leaching. The leaching process of the ion-adsorption type rare earths ore was time-consuming and a lot of leaching solutions were required to be tested in the leaching process. The rare earth leaching solution had many characteristics,such as many elements needing to be tested,great content difference between elements in the same solution and great content difference of the same element in different solutions. In this paper,the test by inductively coupled plasma-atomic emission spectrometry（ICP-AES） of rare earth elements and non-rare earth elements in leaching solution with magnesium salt system of ion-adsorption type rare earths ore was achieved by suitable analytical lines,matrix effect analysis,correcting spectral peak drift and segment treatment,etc. The reliability of method was verified by precision experiment,adding standard recovery experiment,blank experiment and contrast experiment. The results showed that the method detection limit was less than 0. 03 mg·L^（-1）,and the test error and relative standard deviation of tested elements could be less than 5%. The test method by ICP-AES realized the accurate analysis of rare earths,magnesium,calcium,aluminum in leaching solution with magnesium salt system,and the process parameters,such as the true rare earth leaching efficiency,etc.,could be calculated. It provided test support for the recovery of rare earths from weathered crust elution-deposited rare earths ore with magnesium sulfate.