An X-ray fluorescence spectrometric method has been developed for the analysis of high purity erbium oxide for the determination of yttrium, terbium, dysprosium, holmium, thulium, ytterbium and lutetium oxide impurities in the concentration range 0.005–0.1%. The sample is taken in oxalate form, mixed with a binder (boric acid) in the weight ratio 31 and made into a double layer pellet. The analysis is done on a Philips PW 1220 X-ray fluorescence spectrometer using a LiF (200) analyzing crystal. The precision at each concentration of the standards and theoretical minimum detection limit for each element has been calculated.
A wavelength dispersive X-ray fluorescence spectrometric method has been developed for the analysis of thulium oxide to determine the neighbouring rare earth impurities. The sample is taken in oxalate form and the analysis is done on a Philips PW 1220 spectrometer with a LiF (200) crystal. The detection limit for holmium, lutetium and yttrium is 0.002%, for dysprosium and erbium 0.005% and for, ytterbium it is 0.01%. The precision at each concentration of the standards and the theoretical detection limits have been calculated. Intensity correction factors for the line overlaps have been determined.
A method for the determination of lathanum, praseodymium, neodymium and samarium oxides in cerium dioxide has been developed.
The sample in the oxalate form is mixed with the binding material (boric acid) in the ratio 1∶1 pressed to form a double layer
pellet over a boric acid backing pellet and irradiated by X-rays from a tungsten tube. The secondary X-rays are dispersed
with a LiF (200) crystal in a Philips PW 1220 semiautomatic X-ray fluorescence spectrometer. The intensity of fluorescent
X-rays is measured by a flow proportional counter. The minimum determination limit is 0.01% for lanthanum and samarium oxides
and 0.02% for praseodymium and neodymium oxides. The precision at each concentration of the standards and theoretical minimum
determination limit for each element have been calculated.