A group of researchers in the University of Illinois Urbana-Champaign have discovered a new breakthrough in sustainable chemical processing. The researchers used halogen bonding to create a new type of polymer that, when combined with a unique electrochemical process, pulls out only the target materials they want from complex mixtures.
The ‘Electric Sponge’ Breakthrough
You can think about it this way: picture a sponge for the chemicals that you do want to absorb, and whatever is left over stays behind. Albeit the name of what the scholar came up with – a new methodology that they hypothesize is unique to either other work on this topic. This has resulted in a highly selective electrochemical separation system, achieved by the design of a polymer that can control the charge density at a halogen atom upon the arrival of electricity.
The breakthrough hinges on something called halogen bonding. This last analogy is an epitome of the field: halogen bonding has by now long been well studied, yet to no more than a small coterie of chemists. Now researchers are the first to take advantage of that notion and fabricate a functional “sponge” that can be used to capture targeted ions and molecules from multiple, mixed aqueous solutions. The selectivity can be achieved using the high affinity of the ion and substance to the halogen atom due to the strong interaction strength of halogen bonding.
Sustainable Chemical Processing: The Future Is Electric
Chemical separation in the industrial world has long been dominated by heat-driven processes or membrane filtration. However, these solutions are usually wasteful of materials, which is not practical in the long term. A better solution, and one that the researchers have developed, is electrochemical separation.
While electrochemical separation processes exist now for desalination, they have tended to do so without distinction of the same attractive forces that draw harmful contaminants like heavy metals from discarded electronics. This research entails the establishment of a selective in-situ self-separation of specific components from complex mixtures, realised by developing halogen bonding into their polymer system.
The impact of this innovation is broad, ranging from pharmaceuticals to synthetic chemistry. Instead of using energy-intense and waste-producing separation processes, it is now possible for companies to find a more sustainable solution by using electricity to drive selective separation units with high selectivity and purity.
Conclusion
As an example of sustainable chemical processing, the researchers showed selective electrochemical separation through halogen bonding. Their work establishes a foundation for more efficient and environmentally friendly chemical separation techniques by creating redox-responsive polymers that can attract and separate target substances from crowded solutions. The uses of this technology in multiple industries are really exciting as the team gets the process worked down and upscaled.
