FU Guoyan, WANG Weiwei, LV Dong, LIU Cheng
(China ENFI Engineering Technology Co., Ltd, Beijing 100038, China)
Abstract: Submicron Sc2O3 powder was prepared by using oxalic acid precipitation. The effects of reaction temperature, precipitation dosage and pH value on the recovery rate of scandium precipitation were studied. Meanwhile, the Sc2O3 powder was characterized by using XRD, SEM-EDS, laser particle size analyzer, Fourier infrared spectrometer (FTIR) and BET surface area measurement. It is showed that the recovery rate of scandium precipitation could be up to 97%, when the reaction temperature was 80 °C, the molar ratio of oxalic acid to scandium chloride was 1.5 and the pH value was 1.3. According to the TG-DTA, FTIR and XRD results, it is demonstrated that the Sc2O3 was relative pure after the oxalate precursor was calcined at 1100 °C, with pretty high crystallinity. The Sc2O3 powder has fine and uniform particles. Volume center diameter (D50) of the powder was 7.586 μm, while 90% of the particles have a size of less than 16.050 μm, with a normal size distribution profile. The powder exhibits a specific surface area of 17.819 m2/g, while it has a submicron layered structure, with surface containing certain secondary pores.
Key words: precipitation; scandium; oxalate; powder