Breakthrough in valorization of phosphoric acid sludge

Roasting Furnace used to develop method for production of elemental P.
Roasting Furnace used to develop method for production of elemental P.

CMI researchers from Florida Industrial and Phosphate Research Institute (FIPR Institute) and Oak Ridge National Laboratory conducted the research for this highlight.

Innovation
Co-production of REE, phosphate, and elemental P from phosphoric acid sludge. 

Achievement

  • Nearly 100% recovery of high-value elemental P from pre-concentrated phosphoric acid evaporator sludge.
  • High (>93%) REE leaching recovery from the solid residues.
  • Purified and more valuable phosphoric acid centrifuge stream returned to industry.

Significance and Impact

  • Improves the economics for REE recovery from a significant REE resource
  • Potential for >1000 tpa of REEs from domestic mine tailings
  • Produces REEs with over 50% HREE and Y
  • Applicable to different phosphate-containing REE streams
  • Potential to replace current technology, attractive enhancement for industry
  • Accelerates commercialization of REE production from the sludge
  • Positive implications for environmental justice related to waste from phosphoric acid production 

Hub Goal Addressed
Unlocking unconventional resources. Recovery and conversion into high value end products.