top of page
shutterstock_12401600110-edit.jpg

DLE: DIRECT LITHIUM
EXTRACTION

Current lithium production from brine mines, most found in South America, use evaporation ponds to concentrate lithium in a solution and precipitate contaminants as the water volume is reduced. This method requires relatively high lithium concentrations, arid environments to facilitate evaporation, and large tracts of land to hold brine ponds. The average extraction efficiency of lithium using evaporative extraction is between 40-60% and can take between 12-18 months start to finish. Once concentrated, the lithium concentrate can be sent for further purification at a nearby processing facility.


Not everywhere in the world lends itself to evaporative extraction methods. Subsurface brine resources in Canada, the United States, Europe, and even certain regions of South America will require new technologies to unlock their lithium resources.


The most promising technology emerging is Direct Lithium Extraction (DLE). It’s advantageous as it does not require the evaporation of water to concentrate lithium. It selectively pulls the lithium from the water and transfers it to a new solution while the lithium-barren source brine remains relatively unchanged. The DLE technologies, developed so far, have lithium recovery values up to 70 – 95% and, contrary to conventional evaporative techniques, are suitable for lower concentration brines, potentially as low as 60 mg/L.


To put it simply, DLE is a process that can remove small concentrations of lithium from a brine containing high concentrations of other ionic impurities. However, DLE is not just one process. Different companies are developing separate DLE methods for different resources based on the chemistry of the source brine.

EMERGING TECHNOLOGIES

Four technologies are emerging as the leading processes for Direct Lithium Extraction:

EMERGING TECHNOLOGIES
  • 1. LITHIUM SELECTIVITY
    Does the technology favour extraction of the lithium ion over other ions in solution and to what extent does the brine need pre-treatment to remove undesirable ions.
  • 2. CONTAMINANT CARRYOVER
    What concentration of contaminant ions such as Mg, Ca, Mn, and Na are transferred from the brine to the product, whether caused by selectivity or process selection.
  • 3. MATERIAL DEGRADATION
    How long does the extraction material last throughout the chemical process and the lifecycle of the material.
  • 4. LITHIUM RECOVERY
    Source brine’s with relatively small concentrations of lithium make it imperative to have a high overall lithium recovery from source to product.
  • 5. PRODUCT PURITY
    Does the product of DLE lend itself to efficient and cost-effective purification required to produce battery grade lithium chemicals.

Each of these DLE technologies have specific advantages and disadvantages, even within the same family of technology. It is important to note that a successful technology deployed in one part of the world will not be successful in another due to differences in brine chemistries. 


When we look at evaluating the performance of each technology, we consider five key performance indicators:

These five KPI’s for DLE technologies are related in some way and feed into the overall capital and operating expenses that a technology can achieve for a given brine resource.

PRAIRIE LITHIUM'S DLE TECHNOLOGY

Asset 27pl.png

Prairie Lithium’s DLE technology was developed in house by scientists and engineers employed by the company. It is an ion exchange process that uses a proprietary material called Plix (Prairie Lithium Ion Exchange). The Plix material is highly selective to lithium and was developed specifically to work with subsurface brines produced from Prairie Lithium’s resource area.

 

Prairie Lithium is diligently working to scale the Plix technology and process to commercial production of lithium chemicals. Moving from the lab to an operational environment with a successful concept is one of the biggest challenges currently faced by DLE developers.

Below is a general schematic of how Plix takes a brine with a lithium concentration of 111 mg/L and converts it into a concentrated LiCl solution suitable for purification of battery grade lithium chemicals.

PRAIRIE LITHIUM'S DLE
DLE: LOADING

LOADING

  • Fresh PLIX is mixed with lithium rich brine

  • Lithium exchanges with hydrogen into the PLIX crystal structure

  • The lithium depleted brine is separated from the PLIX and sent to disposal

  • The lithium rich PLIX is ready for desorption

Asset 14Plix.png

LITHIUM
RICH BRINE

Asset 6Plix.png
Asset 7Plix.png

STRIPPING

  • Fresh PLIX is mixed with lithium rich brine

  • Lithium exchanges with hydrogen into the PLIX crystal structure

  • The lithium depleted brine is separated from the PLIX and sent to disposal

  • The lithium rich PLIX is ready for desorption

Asset 14Plix.png

HYDROCHLORIC ACID

Asset 10Plix.png
Asset 5Plix.png
Asset 13Plix.png
DLE: STRIPPING

SEPARATION

  • The regenerated PLIX is separated from the lithium chloride solution

  • Regenerated PLIX is used in a new adsorption cycle

  • Concentrated lithium chloride is sent for purification and manufacturing

DLE: SEPERATION
bottom of page