Determination of total ionic-phase rare earth and component in ion-adsorption rare earth ore by inductively coupled plasma mass spectrometry

The ionic-phase rare earth in raw ores of ion-adsorption rare earth was extracted by ammonium sulfate and the calibration solution series were prepared with ammonium sulfate solution as matrix.Thus,a method for the determination of total ionic-phase rare earth and component in the sample solution was established by inductively coupled plasma mass spectrometry(ICP-MS).It showed that ionic-phase rare earth could be effectively extracted from 10.00 g of ion-adsorption rare earth ore samples which had been concussed for 15 min with 100 mL of 50g/L ammonium sulfate solution added and kept still for 30min;5.0g/L ammonium sulfate solution was used for matrix matching of calibration solution series,while 103 Rh-185 Re double inner standard method was used to calibrate the matrix effect of ammonium sulfate and the signal shift effect of instrument;the possible mass spectral interference was eliminated with appropriate isotopes.Under optimal conditions,the linear correlation coefficient of the calibration curve of fifteen rare earth elements within 10.0-100.0μg/L were all larger than 0.999 91.The detection limit was 0.10-0.66μg/g.When the method was employed to determine total ionic-phase rare earth and component in different ion-adsorption rare earth ore zones,the results were consistent with those obtained by inductively coupled plasma atomic emission spectrometry(ICPAES).The relative standard deviation(RSD,n=11)was in the range of 1.0%-5.2%,and the recovery was between 98%and 104%.