Process Test-work Progress Update

CleanTech Lithium PLC (AIM:CTL), an innovative sustainable lithium developer in Chile, is collaborating with DuPont Water Solutions, a business unit of DuPont, to test lithium processing technology. DuPont has developed a new nanofiltration (NF) membrane technology which aims to remove impurities and maximise lithium recovery. NF is applied in CleanTech Lithium's direct lithium extraction (DLE) downstream process. Trials have recently been completed with highly encouraging results.

Test-work Highlights:

• Test-work on lithium processing technology, a new nanofiltration (NF) membrane technology, for high lithium recovery developed by Dupont Water Solutions
• The test-work focused on processing two different concentrations of eluate produced from CleanTech Lithium´s DLE pilot plant in Chile, and measured the key metrics of impurity removal and lithium recovery
• The first trial was based on eluate representative of the average produced from the Company´s DLE pilot plant, while the second trial applied to eluate that had been concentrated approximately 4 times higher by forward osmosis
• The primary impurities targeted by NF are Calcium and Magnesium which showed very high rejection rates while lithium recovery rates were 94% and 92%:

• The results were in line or exceeded the expected design parameters provided by Dupont Water Solutions with performance minimally impacted by feed concentration
• The membranes were designed to run at a higher pressure than that trialled which would likely increase the lithium recovery rates and reduce reprocess volumes to recover the rejected lithium
• The effectiveness of the NF membrane at high eluate concentrations is positive for application of the technology at much lower feed volumes, reducing Capex and Opex costs

Commenting, Ignacio Mehech, Chief Executive Officer, of Cleantech Lithium PLC, said:

"These highly encouraging results mark an important step in our collaboration with DuPont Water Solutions. Calcium and magnesium are among the most difficult impurities to remove in the lithium extraction process, and DuPont's nanofiltration technology has demonstrated excellent rejection rates while maintaining high lithium recovery. This supports our approach to sustainable lithium production and signals the potential for reduced capital and operating costs as we progress towards commercialisation."

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