| Popis: |
Calcination of Nd3+-form, “Dowex”† 50W-X8 resin in air or oxygen yields Nd2O2SO4 at 600–1000°C and Nd2O3 at 1200°C and above. Pyrolysis in vacuum or nitrogen at 1000°C yields carbon and Nd2O2S. Sulfonic acid groups are reduced by the hydrocarbon matrix at ∼400°C, releasing H2S, CO, and CO2. Resin calcination is proposed for preparing californium and curium oxides from ion exchange eluants. Ion exchange eluant containing Nd (as a stand-in for Cf and Cm) and DTPA was acidified to 0·2M HNO3, Nd was absorbed onto H+-form resin, and the resin was calcined to the pure oxysulfate and to the pure oxide. Both products are porous and will dissolve in hot 0·1 M HNO3. |
