Treatment of fluid catalytic cracking spent catalysts to recover lanthanum and cerium: Comparison between selective precipitation and solvent extraction

摘要

The paper is focused on the study of hydrometallurgical processes for recovery of rare earths (RE) from fluid catalytic cracking catalysts (FCCC). According to the experimental results two processes were proposed: in the first one RE were recovered as double sulfates by selective precipitation with sodium hydroxide after leaching with sulfuric acid. The second approach consisted of dissolution of powder by acids, solvent extraction by (2-ethylhexyl)phosphoric acid (D2EHPA), stripping and precipitation of RE oxalates using oxalic acid.