Quantification of Trace and Ultra-trace Impurities in U-Zr Alloy by Inductively Couple Plasma Time of Flight Mass Spectrometry (ICP-TOF-MS) After Simultaneous Separation of U and Zr

摘要

A methodology has been developed for the determination of trace and ultra-trace metallic impurities in U-Zr alloy fuel by inductively coupled plasma mass spectrometry (ICP-MS) after solvent extraction of the bulk matrix. A detailed study was performed to optimize the concentration of tri-n-octyl phosphine oxide (TOPO), tri-n-butyl phosphate (TBP), nitric acid, and hydrochloric acid for maximum removal of the matrix elements (U and Zr). The ratio of metal oxide to metal (MO+/M+) and doubly charged to singly charged zirconium (Zr++/Zr+) was studied for correction of spectroscopic interference. The non-spectroscopic matrix effect was studied for rare earth and cadmium. The standard addition method was performed for recovery study of the trace and ultra-trace elements. Recovery of 36 elements (Al, Ba, Bi, Cd, Ce, Co, Cr, Cs, Dy, Eu, Er, Ga, Gd, Ir, Ho, La, Lu, Mn, Nd, Ni, Pb, Pr, Pt, Rh, Rb, Ru, Sc, Sm, Sr,Tb, Te, Tm, V, Y, and Yb) was found to be more than 90% with the %RSD 10. The matrix (U&Zr) concentration after separation was 10 mu g mL(-1). The instrumental detection limit (IDL) and method detection limit (MDL) were found to be in the range 0.01-1.1 mu g L-1 and 1.0-25.0 mu g kg(-1), respectively. The separation method was validated using (152)+Eu-154 as tracer for the rare earth elements.