AFTRE: HF-free route to rare-earth fluorides

X-ray diffraction (XRD) pattern of NdF3 synthesized via AFTRE.
X-ray diffraction (XRD) pattern of NdF3 synthesized via AFTRE.

CMI researchers at Ames National Laboratory conducted the research for this highlight

Innovation 
AFTRE (Alternative Fluorination Technology for Rare‑Earths) is an HF‑free fluorination platform addressing a critical domestic gap in rare‑earth trifluoride (REF3) precursor production. It enables safer, scalable, and supply‑chain‑resilient pathways to rare‑earth metals and permanent magnets.

Achievement

  • AFTRE eliminates the use of HF in the synthesis of REF3 precursors used for rare-earth metal production and related applications.
  • Distinct from REMAFS, which employs alternative salt chemistries for metallization, AFTRE produces conventional REF3 while remaining HF‑free.
  • AFTRE enables room‑temperature REF3 synthesis, eliminates HF‑based dehydration and drying steps and offers multiple production pathways.

Significance and Impact

  • Removes one of the most hazardous, capital-intensive, and supply-chain-limiting steps in rare-earth metal manufacturing.
  • Compatible with existing and emerging metal production flowsheets.
  • Improves techno‑economic viability by reducing regulatory burden, waste handling, and infrastructure requirements associated with HF‑based fluorination.

Hub Target Addressed
Cost-efficient domestic rare earth metals production.
 

Quadrupole mass-ion detection (QMID) analysis confirming no detectable HF evolution during drying of AFTRE-derived NdF3.
Quadrupole mass-ion detection (QMID) analysis confirming no detectable HF evolution during drying of AFTRE-derived NdF.