Cypress Development Announces Further Advancement in Chloride Leaching for Clayton Valley Lithium Project in Nevada

VANCOUVER, British Columbia, Jan. 28, 2021 (GLOBE NEWSWIRE) -- Cypress Development Corp. (TSX-V: CYP) (OTCQB: CYDVF) (Frankfurt: C1Z1) (“Cypress” or “the Company”) reports additional valuable advances in the Company’s scoping-level study of chloride-based leaching to recover lithium from the claystone at its Clayton Valley Lithium Project. As described in the December 3^rd and 16^th 2020 news releases, the Company initiated an investigation into chloride-based leaching and the potential economic and environmental benefits over sulfide-based leaching. Progress to date indicates a positive alternative to a sulfate-based approach and merits consideration for the Company’s upcoming pilot plant program.

Test work completed on 200- to 400-g samples of claystone used hydrochloric acid (HCl) and sodium chloride (NaCl) brine as the leach solution. Test results from this work determined the optimum parameters for leaching temperature, acid strength, and retention time. The data were used to conduct a test on a 33 kg sample of claystone which yielded greater than 81% extraction of the lithium into solution. The Company identifies this as a starting point for the pilot plant program to expand upon these results and demonstrate that they are sustainably operational on a larger scale.

Samples of the leach slurry were tested by Pocock Industrial, Inc. to address solid-liquid separation through standard and high-density thickeners, and vacuum and pressure filtration. The results indicate potential benefits that include faster filtration and settling rates with the utilization of standard thickeners and filtration equipment. The differences in settling and filtration rates also mean processing may be accomplished with significantly less make-up water. With the chloride-based approach, the leach solution is amenable to standard processes to recover the lithium and potentially other products.

“The Company is pleased with the results from our scoping study,” said Cypress CEO Bill Willoughby. “Chloride-based leaching represents an alternative to sulfuric acid and could be impactful in the areas of economy, process and the environment. There are still important trade-offs to consider with respect to power and acid supply, as well as some remaining analyses, but this is an alternative that will most likely become the focus of the pilot plant program. This work is critical to our goal of advancing the Clayton Valley Lithium Project towards a feasibility study later this year.”