LithiumBank’s DLE tests in Alberta produce average grade of 3,100 mg/L
LithiumBank Resources (TSXV: LBNK) said the desorption component of its first direct lithium extraction (DLE) pilot plant tests in Calgary, Alberta, has produced an average of 3,100 mg/L lithium from a composite eluate after rejection of over 99% of the impurities.
Multiple lithium-rich liquors (eluates) ranging from 2,600 mg/L lithium to 4,000 mg/L lithium were made and then blended to create the composite eluate, which was then used as feedstock for refinery and downstream laboratory tests to produce a battery-grade lithium carbonate product of more than 99.95% purity.
LithiumBank has a portfolio of direct brine lithium projects, including Boardwalk and Park Place in west-central Alberta.
In September, the company announced that brine from the Boardwalk salar was processed through the adsorption circuit of the pilot plant and achieved lithium recovery of over 98%. The sorbent was then manually processed to desorb the lithium from the sorbent using a dilute sulphuric acid solution, producing the high-grade eluate.
The eluate quality reported is the result of a single cycle. Eluate grade and purity were largely in line with results predicted from previous test work at a lab scale announced in November 2023, LithiumBank said.
The company added that the recent desorption tests were consistent with its goals to minimize the flow volume and reagent costs. The average lithium upgrade from the feed was a factor of 44 times, while the low-cost sulphuric acid provided excellent rejection of impurities (calcium, strontium and barium).
Preliminary purification
As an extension of the desorption campaign, preliminary purification of the eluate was undertaken at the Calgary facility. The process used low-cost, industrial-grade reagents and demonstrated the ability to further reduce the impurity load on the downstream refinery.
This preliminary purification, LithiumBank said, further increased the rejection of impurities without materially impacting the eluate grade.
A 5-litre sample of the composite eluate was further refined into battery grade lithium carbonate by Telescope Innovations using their proprietary ReCRFT recrystallization process. The DLE eluate was initially concentrated by evaporation, carbonated to form a crude lithium carbonate, and then processed into battery-grade lithium carbonate.
The brine that was processed by the adsorption circuit of the pilot plant was collected within the hydrocarbon zone from four wells in the indicated resource area of Boardwalk.
In future piloting campaigns, LithiumBank expects to process brine from the company’s own licensed well, where it has recently completed drilling. So far, it has collected 248 cubic metres of brine from below the hydrocarbon zone for piloting purposes.
