We are a professional team specializing in lithium extraction technology, committed to providing the best lithium extraction solutions for both lithium ore resources and brine lithium resources. We have partnered with China's top universities: Central South University, Shanghai Jiao Tong University, and the China Mining Research Institute to conduct long-term research in this field.
We have multiple successful application cases in China, including Tibet and Qinghai, and have developed three technical routes for brine lithium extraction. These three methods include DLE lithium extraction technology, adsorption and membrane concentration technology, and electrochemical stripping method.
In this article, we will introduce each of these three methods to provide a comparison and selection guide for the composition and characteristics of Bolivia's local salt lake brine.
DLE lithium extraction technology is a new type of lithium extraction technology, which stands for "Direct Lithium Extraction-Extractive Recovery." It is a lithium resource extraction technology that has developed in recent years. The principle of lithium extraction is to selectively adsorb lithium ions from brine using a special adsorbent and then desorb them under certain conditions to extract lithium.
The DLE lithium extraction technology method we propose is a comprehensive composite DLE technology, which mainly includes the following steps:
(1) Lithium salt solution pretreatment: pretreat the lithium salt solution, such as removing impurities and adjusting the pH value to improve the subsequent adsorbent and desorption efficiency.
(2) Lithium ion adsorption: pass the pretreated brine solution through the adsorbent bed to adsorb lithium ions onto the surface of the adsorbent.
(3) Adsorbent recovery: extract the adsorbent and adsorbed lithium ions from the processing unit and carry out subsequent treatment and recovery.
(4) Lithium ion desorption: desorb lithium ions from the adsorbent into the solution to obtain the enriched lithium ion solution.
(5) Post-treatment of enriched lithium ion solution: carry out subsequent treatment such as impurity removal and concentration to obtain high-purity lithium salt products.
Compared with traditional lithium extraction methods, DLE lithium extraction technology has advantages such as high extraction efficiency, low operating cost, and environmental friendliness.
Adsorption method is a chemical separation method that uses an adsorbent to adsorb and desorb metal ions to achieve separation and purification of the metal. In terms of lithium extraction, the adsorption method can use an adsorbent to adsorb lithium ions and then desorb them from the adsorbent using an acid washing solution under acidic conditions.
We have improved the lithium extraction method using the adsorption method to increase extraction efficiency. The improved lithium extraction method using the adsorption method mainly includes the following steps:
(1) Collect brine from potassium-magnesium salt lake, and subject it to pre-treatment processes such as impurity removal, filtration, and pH adjustment to ensure that lithium meets the requirements for extraction by adsorption and attachment in terms of granularity, distribution, and other aspects.
(2) Mix the adsorbent with lithium resources, and allow the adsorbent to adsorb lithium ions, forming an adsorbent containing lithium.
(3) Add the adsorbent containing lithium to acid washing solution, and subject it to stirring, heating, and other processes to detach lithium ions from the adsorbent and react with sulfate in the acid washing solution, forming lithium sulfate.
(4) Through processes such as precipitation, filtration, and crystallization, purify lithium sulfate into high-purity lithium products.
The advantages of the improved adsorption and attachment method for lithium extraction are as follows compared to traditional methods:
(1) Increased efficiency and purity of lithium extraction.
(2) Savings in energy and raw material consumption.
(3) Reduced environmental pollution.
In order to further improve the efficiency of lithium extraction, we have collaborated with the lithium research team at Central South University to jointly develop a method for extracting lithium using the electrochemical deintercalation method, which is currently in the pilot stage, and we plan to carry out large-scale demonstration and application in the second half of the year.
The principle of this method for extracting lithium is a chemical separation method that utilizes an applied electric field to remove and deposit metal ions. Through electrochemical reactions, metal ions are deintercalated from the electrode surface, and pure metal is deposited on the other electrode, thus achieving the separation and purification of metals. In the case of lithium extraction, the electrochemical deintercalation method allows for the reaction of lithium ions with the negative electrode material, resulting in the deintercalation of lithium ions.
The electrochemical deintercalation method for extracting lithium mainly involves the following steps:
(1) Pre-treat the brine from the salt lake by removing impurities, filtration, and pH adjustment to ensure that lithium meets the requirements for electrochemical deintercalation.
(2) Add the lithium resource to the electrolyte and apply a voltage to the negative electrode material, allowing lithium ions to be deintercalated from the electrolyte and form an electrode material containing lithium.
(3) Mix the electrode material containing lithium with pure electrolyte and apply a voltage to the positive electrode material, allowing lithium ions to be deposited onto the positive electrode material and form pure lithium.
Compared to traditional methods for extracting lithium, the electrochemical deintercalation method has the following advantages:
(1) Increased efficiency and purity of lithium extraction.
(2) Savings in energy and raw material consumption.
(3) Reduced environmental pollution.
The above are our three available options for lithium extraction technology. Based on the specific conditions of the local salt lake in Bolivia and after our previous survey, sample analysis, and small-scale testing, we can form the optimal method that balances efficiency and cost-effectiveness, and strongly promote our cooperation.