Determination of Total Ion-phase Rare Earth Content in an Ionic-adsorption Rare Earth Ore by ICP-MS

Objective At present, there is no national standard for the determination of total ion-adsorbed rare earth elements in China, and relevant industry standards are generally adopted for detection. However, these standards fail to specify key parameters such as leaching temperature, which makes it impossible to evaluate the value of ion-adsorbed rare earth elements accurately, scientifically and effectively. To address this problem, taking an ion-adsorbed rare earth ore from Fujian Province as the research object, a method for determining the total amount of ion-adsorbed rare earth elements was established by optimizing leaching conditions combined with inductively coupled plasma mass spectrometry (ICP-MS). Method In this study, the effects of leaching agent type, oscillation time, oscillation frequency and leaching temperature on the leaching efficiency of rare earth elements were systematically investigated. Finally, it was determined that oscillating leaching of the sample at 20 ℃ and 160 r/min for 1.5 h could effectively leach the ion-adsorbed rare earth elements, and the leachate was then determined by ICP-MS. Result Through the tests of method precision and standard addition recovery, the results showed that the precision (RSD, n = 12) of the method ranged from 4.00% to 4.29%, and the accuracy (standard addition recovery rate) was between 95.3% and 102.3%. The established method for determining the total amount of ion-adsorbed rare earth elements is simple to operate, rapid and efficient, with its precision and accuracy both meeting the detection specifications. Conclusion It is suitable for the routine determination of ion-adsorbed rare earth content in the ores of this mining area, providing scientific data support for the reserve assessment, development and utilization, as well as process optimization of the ion-adsorbed rare earth ores in the mining area.