Determination of In and Ga in plutonium oxide matrix by ICP-AES after chemical separation

An analytical method was developed for the determination of indium and gallium in plutonium samples. A solvent extraction technique was employed by using 30% TBP in CCl4 for the quantitative separation of plutonium from the sample solution and subsequent determination by radial inductively coupled plasma atomic emission spectrometry (ICP-AES). The quantitative recovery of In and Ga in the separated samples was confirmed from radiometric/tracer studies. Recording of spectral profile at 303.396 nm for In and 403.298 nm for Ga has clearly indicated that the determination of Ga and In at lower concentrations will be affected by the presence of significant amounts of residual Pu in the aqueous phase due to spectral interference. These elements can be determined from ppm to % levels by proper dilution with 1 M HNO3 and appropriate (100 mg and 1 g) sample size. The analytical range obtained for Ga and In was 0.1-1000 μg/mL and 0.05-500 μg/mL respectively by ICP-AES. Synthetic samples of plutonium containing indium and gallium in the range of 50-20000 ppm were analyzed. (orig.)