Arafura Resources Limited’s (ASX:ARU) phase 6 pilot plant has successfully produced neodymium-praseodymium (NdPr) enriched rare earth chloride using material from its Nolans NdPr Project in the Northern Territory.
Phase 6 of the pilot program – rare earth dissolution and evaporation – targeted the removal of low value, high volume cerium from rare earth hydroxide to produce rare earth chloride.
NdPr-enriched rare earth chloride liquor
This process reduces the volume of material that feeds into rare earth separation resulting in a smaller and more efficient separation plant that will focus on the production of high-value rare earth products such as NdPr oxide.
Arafura’s rare earth processing pilot plant at ALS Metallurgical Services in Perth ran continuously for seven days, processing rare earth hydroxide precipitate from the phase 6 pilot plant.
The company has confirmed that more than 99.5% of the cerium has been rejected from the rare earth chloride during steady state operation of the pilot.
The cerium rejection process represents valuable intellectual property and a significant downstream operational advantage over traditional separation circuits run by other rare earth companies.
Arafura’s flowsheet for rare earth processing at Nolans, which incorporates cerium rejection, is currently the subject of a patent application.
The phase 6 pilot plant is now in the final stages of decommissioning.
Arafura managing director Gavin Lockyer said: “The successful operation of our rare earth processing pilot plant marks the conclusion of the large-scale validation of our process flowsheet.
“We have developed and applied a number of process innovations across the flowsheet, including cerium removal prior to rare earth separation.
“Reagent consumption data from this latest phase of piloting are now being used to inform final plant design and costings in the definitive feasibility study.
“The results of the study are expected by early February.”