Cerium and neodymium co-precipitation in molten chloride by wet argon sparging

Co-precipitations of cerium (III) and neodymium (III) at 10 wt.% in LiCl–CaCl2 (30-70 mol%) molten salt at 705 °C have been achieved using an original way of precipitation, wet argon sparging. Several CeCl3/NdCl3 ratios have been studied, and the isolated powders were analyzed using different characterization methods including XRD investigations. The lanthanides precipitation yields have been determined around 99.9% using ICP-AES analysis. XRD demonstrated that the precipitates mainly contained mixed oxychloride (Ce1−xNdx)OCl and a small amount of the mixed oxide Ce1−yNdyO2−0.5y. Calcination of these precipitates has resulted in the cerium and neodymium mixed oxides. For the precipitation with a Ce/Nd = 50/50 ratio, an hydroxychloride Ln(OH)2Cl and the oxychloride CeIV(Nd0.7Ce0.3)IIIO3Cl have been identified as unexpected intermediate compounds.