Progress in capacitive deionization technology improves seawater desalination performance

Recently, the Institute of Solid State Physics, Hefei Institute of Physical Science, Chinese Academy of Sciences has developed a three-dimensional foam current collector for seawater desalination based on capacitive deionization technology.
Its unique foam structure is used to enhance the charge transport between the current collector and the carbon slurry.
Significantly improve seawater desalination performance
.

Researchers have developed a three-dimensional foam-structured current collector to enhance the desalination performance of flowing electrode capacitive deionization (FCDI), taking advantage of its complex mass transfer channels, small charge transport distances within the channels, and large charge transport on the foam surface.
area to improve the charge transport of the current collector to the carbon paste
.

Compared with the traditional FCDI device, the new three-dimensional foam current collector replaces the traditional two-dimensional planar current collector, which enables the carbon slurry in the flow channel to better complete the charge transport process and improves the desalination capacity of the FCDI device
.
The electric field and flow field simulations of current collectors with different pore sizes show that when the pore size is 30 pore density (ppi), the foam current collector has fewer low flow rate regions and larger effective charge transport regions
.
Meanwhile, in the desalination experiments, it was found that the foam current collector of 30 ppi had an average desalination rate of 3.
29 μmol/cm 2 min and a charge transport efficiency of 93%
.

The researchers further conducted desalination tests on simulated seawater, the South China Sea and the Yellow Sea, respectively.
The results showed that the three-dimensional foam current collector FCDI device has excellent seawater desalination performance, with a desalination rate of 99.
9%, which can successfully desalinate seawater
.
This work has far-reaching significance for the development and industrialization of subsequent capacitive deionization technology in the field of water purification
.

Compared with traditional reverse osmosis and electrodialysis technologies, capacitive deionization (CDI) technology, as an emerging seawater desalination technology, has unique advantages, such as high energy utilization efficiency, relatively low cost and environmental impact.
It is very friendly and has received extensive attention from researchers in recent years
.
Among them, FCDI, as a branch of capacitive deionization technology, utilizes the principle that activated carbon aqueous solution forms an electric double layer in the device to adsorb salt ions.
With pseudo-infinite adsorption capacity and high salt ion adsorption rate, FCDI is considered to be efficient for desalination of seawater and Powerful technology for resource enrichment and enrichment
.
However, the current FCDI process still has problems such as limited charge transport area and large charge transport distance, which weakens the charge transport ability of the current collector to the activated carbon aqueous solution and reduces the desalination performance of the FCDI device
.
Therefore, optimizing the current collector, thereby expanding the charge transport area and reducing the charge transport distance, is crucial for improving the desalination performance of FCDI and promoting the industrialization of seawater purification
.