Lithium Recovery Processing interestingLithium Recovery Processing. Lithium is recovered from two basic sources: hard rock deposits containing the lithium bearing minerals spodumene and lepidolite, and brine deposits hosted by evaporate salts containing lithium. These brine deposits contain numerous other mineral salts and soluble compounds such as magnesium, sodium, calcium, potassium, boron and others. Research also continues to develop economic ways to recover lithium from clays such as hectorite. Research is also being done on better ways to extract lithium in new, more efficient ways. The western states contain many evaporite or so called “dry lake” or “salar” deposits that contain mineral brines. Examples are Searles Lake, near Trona, California; the Great Salt Lake in Utah; Dead Man’s Lake in California; and many more. While these all contain various brine compounds, not all of these lakes contain sufficient lithium minerals for economic recovery. The most lithium-rich dry lake deposits tend to be those which drain large areas of felsic volcanic rocks. The Clayton Valley Silver Peak basin contains concentrations of numerous mineral salts including magnesium, lithium, sodium, calcium and strontium. This deposit is a special case of lithium deposition as it is in a basin that is the center of a vast area of extensive volcanic rocks, such as rhyolite, dacite, andesite and other flows, plus hot springs containing elevated lithium contents. Since lithium is water soluble, it is leached from these rocks and can accumulate in the near-surface waters and be enriched through evaporation over long periods of time. Extensive drilling and pump testing by Pure Energy has delineated a large lithium-bearing brine resource in addition to that held by Albermarle for its Silver Peak operation. After determining the economic reserve potential of the lithium brine source, Pure Energy shipped samples of the brine to Tenova Advanced Technology of Israel to perform bench testing of a new process for lithium recovery. Tenova then produced approximately 20 tons of simulated Clayton Valley brine for processing through their mini-pilot plant in Israel. The more extensive mini-pilot plant provided enough data for estimates of recovery and the design of preliminary process flowsheets. The new solvent extraction process directly takes lithium out of the brine water. During the extraction process, the lithium in the brine moves into a collector material from which it is later recovered. This allows the extraction to be done with a very small land footprint, so it does not require extensive evaporation ponds, with no long lead time evaporative processing all while consuming much less ground water than the old technology (as the brine water is returned to the aquifer after the lithium is extracted). The resulting combination not 12/7/2017 New Technology for Extracting Lithium To Be Tested in Nevada | ICMJs Prospecting and Mining Journal https://www.icmj.com/magazine/print-article/new-technology-for-extracting-lithium-to-be-tested-in-nevada-3738/ 2/2 only results in a faster path to lithium production at potentially lower costs, but is much more environmentally friendly. Similar solvent extraction methods are being studied by a number of researchers, but this will be the first commercial-scale plant. Pure Energy, in conjunction with Tenova Advanced Technology and SUEZ, formerly General Electric Water and Process Technologies, has developed a pilot plant to process lithium brines using the new solvent extraction technology. Production of the Lithium will be completed in a 48-hour process with much less waste and a substantial increase of recovery rates from around 40% with conventional evaporation to near 90%. Pure Energy now plans to construct a continuous process pilot plant to be located near the town of Silver Peak. If the pilot plant trial is successful and the process is verified, they can develop detailed engineering and designs and a full-size plant will be constructed. It would be the first-of-its-kind commercial plant and would be built to produce about 12,600 tons per year of high purity lithium hydroxide from a well-head brine source averaging only 123 milligrams of lithium per liter of water. The Tenova liquid extraction process technology may allow development of lithium deposits previously considered as sub-economic. There is also the possibility for reduction or elimination of permitting problems stemming from extensive water use requirements and large areas of disturbance caused by evaporation ponds
https://www.icmj.com/magazine/print-article/new-technology-for-extracting-lithium-to-be-tested-in-nevada-3738/