Academy of Finland
Funding decision
Name Sainio, Tuomo
Organisation LUT
Project title
Recovery of rare earth elements from phosphogypsum
Decision No. 297120
Decision date 21.12.2015
Funding period 01.03.2016 - 28.02.2019
Funding 128 610
WebFOCUS Report
Project description
Millions of tons of rare earth elements (REE) are locked in phosphogypsum (PG) that is formed in phosphate fertilizer production. The objective of this research was to develop techonology for recovering REEs from PG and solutions that have been in contact with PG. Characterization of PG revealed that small particles (<45micrometers) have higher REE content than large partciles. Intensification of acid leaching using polymeric separation materials was studied with commercial and novel resins. Chelating resins yielded higher purity (20%) than conventional resins (3%). The results obtained make resin-in-leach technology a very attractive process option. In order to mitigate the environmental effects of piling, PG filtrates were treated with sulfate reducing bacteria. High removal of sulphate and recovery of REE were obtained. This approach could be used in passive treatment of PG piles.