CleanTech reports positive results from DuPont membrane testing

(Sharecast News) - CleanTech Lithium has announced positive results from trials of DuPont Water Solutions' nanofiltration (NF) membrane technology on Monday, which was being tested as part of the company's direct lithium extraction (DLE) process in Chile. The AIM-traded firm said the test-work was focussed on two types of eluate produced from CleanTech's DLE pilot plant - one at standard concentration and one concentrated roughly fourfold using forward osmosis.

It said the NF technology aimed to enhance lithium recovery while removing key impurities, particularly calcium and magnesium.

Lithium recovery rates of 94% and 92% were achieved in the respective trials, with calcium and magnesium rejection rates reaching as high as 97%.

The results met or exceeded DuPont's design expectations and demonstrated consistent membrane performance regardless of feed concentration.

CleanTech said the membranes were tested at a lower pressure than their intended design range, adding that higher operating pressures would likely boost lithium recovery further and reduce the need for reprocessing rejected material.

The success of the technology at higher eluate concentrations suggested potential for lower feed volumes, which the board said could reduce both capital and operating expenditure in future plant designs.

CleanTech said the findings supported continued development of its DLE process as it aimed to deliver sustainable lithium production in Chile.

At 1151 BST, shares in CleanTech Lithium were up 3.67% at 6.22p.

Reporting by Josh White for Sharecast.com.