Separation of Cerium from Neodymium Hydroxide Concentrate Through Decomposition and Leaching Using HNO3

Abstract

Abstract The thermal decomposition or calcination of neodymium hydroxide concentrate product by pilot plant of REOH into CeO2, La2O3 and Nd hydroxide concentrate in Center for Accelerator Science and Technology has been performed. From the result of start-up and validation was obtained neodymium hydroxide concentrate which still containing of impurities especially Ce. The purpose of this research to separate Ce from Nd(OH)3 concentrate by thermal decomposition to form Nd oxide (Nd2O3). Calcination temperature was 1000°C, and variation of time. The result of calcination were dissolved using aqueous HNO3 with molarity variation and the level of leaching was five times. From the results, it can be stated that calcination could convert Nd(OH)3 concentrate to Nd2O3 concentrate. Cerium hydroxide was easy dissolve in aqueous HNO3 while CeO2 couldn’t. The longer of calcination time, the formed of Nd2O3 is more perfect. The results of 3 hours calcination for the %weight of La increase until 12,50%, Ce increase to 10,42% and Nd increase to 52,08%. The composition of La in solid of leaching products use 1 M HNO3 with five leaching times is 3,57%, while Ce is 50.26% and Nd is 0.36%. The kinetic calcination and leaching followed reaction control.