A diaphragm-free electrochemical lithium extraction system and lithium extraction method thereof

Abstract

The invention relates to a continuous electrochemical lithium extraction system without a diaphragm and a lithium extraction method thereof. The system is mainly composed of an electrolytic tank, a washing tank, a power supply, a series of lithium absorbing and desorbing electrodes and an electronic balance electrode. Among them, the electrolytic cell is divided by a series of separators into raw material pools and recovery pools which alternate in sequence, and different raw material pools and recovery pools are connected in series through connecting pipes. The lithium raw material to be extracted and the recovery solution are respectively introduced into the raw material pool and the recovery pool, and lithium is separated from the raw material and enriched in the recovery solution by switching electrodes between the raw material pool and the recovery pool. The system is easy to increase or decrease the number of electrolytic cell stages, or control the frequency of electrode position exchange, so as to meet the lithium extraction requirements of different lithium-containing solutions. In the process of lithium extraction, the raw material and recovery liquid circuits are independent and run continuously, so continuous electrochemical lithium extraction can be realized. In addition, since the lithium extraction process only involves the regular movement of electrodes, it is easy to realize automatic operation.

Description

technical field [0001] The invention belongs to the field of inorganic chemical industry and relates to the separation and extraction of elements, in particular to a continuous electrochemical lithium extraction system without diaphragm and a lithium extraction method thereof. Background technique [0002] Nearly 40 million tons of lithium resources have been identified in the world, of which the reserves in brine (including salt lake brine, underground brine, concentrated seawater, etc.) account for about 70% of the total reserves. Due to the unrestrained exploitation of limited high-quality solid ore resources and the cost and scale advantages of extracting lithium from brine, the development and utilization of lithium brine resources has become an inevitable trend. [0003] Based on the principle of lithium-ion batteries, the use of electrochemical ion pump technology to extract lithium from complex brines has become the most advanced technology in current research. Elec...

AI Technical Summary

Problems solved by technology

However, during the lithium extraction process of this device, the adsorption and desorption of lithium are carried out independently and alternately step by step, so continuous lithium extraction operation cannot be realized.

Although the patent CN201811172404.3 discloses a continuous electrochemical element extraction system, the lithium extraction system uses an anion exchange membrane, and only one electrode is transferred from the extraction tank to the recovery tank at a time, so the extraction efficiency of lithium is low and high energy consumption

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