Skip to main content

MIT has created a filter-free water desalination process that relies on electrical shockwaves

Shock electrodialysis desalination - fracking pond toxic wastewater
Image used with permission by copyright holder
The dwindling availability of potable water for communities around the world has inspired many fresh takes on water purification. An MIT chemical engineering team has developed a new desalination process that separates salt from water using an electrically driven shockwave. Constantly pushing apart pure water molecules and the larger atoms of sodium and chlorine in a single stream of water makes it possible to repurpose salt water and even toxic wastewater for drinking purposes, without the long-term sustainability obstacles of traditional desalination processes.

The technique, known as shock electrodialysis, is unique because it’s a “membraneless separation system”. Traditional desalination processes typically use reverse osmosis or electrodialysis to pull apart water molecules and salt particles on either side of a one-way separation membrane. Filtration systems that require this kind of separation can be extremely ineffective as the membranes become clogged. Even the unclogging solutions proposed for membrane separation systems, like boiling, require large amounts of energy to be expended on a regular basis.

MIT shock electrodialysis desalination demonstration chemistry
Image used with permission by copyright holder

Chemical engineering and mathematics professor Martin Bazant and his team of student researchers use shock electrodialysis to circumvent issues like clogging in a system that, superficially, looks very similar to traditional desalination techniques. Because their system still requires some physical separation of water molecules and salt particles, Bazant and his team use a porous material composed of many tiny glass particles, called a frit. Either membranes or electrodes can be used to surround the system, so that when an electric current is applied, water divides itself into two regions of the stream; one with purified water and one with salt water.

When the electric current applied to the system is strong enough, it generates a shockwave that immediately and precisely divides fresh water from salty water. Even when shock electrodialysis is applied with the membranes surrounding the frit, the water flowing across the surface of the membranes (instead of passing through the membrane) helps to mitigate the issue of clogging over time. However, questions remain as to the amount of energy that would be required to power a system like this when scaled up for real world applications.

The MIT team credits Juan Santiago at Stanford University for first discovering the use of a shockwave to separate salt concentration in water, but Santiago’s discovery wasn’t used for desalination applications until now. Bazant believes that shock electrodialysis could be easily scaled for massive desalination plants or water purification systems. Beyond desalination, the system could also be used to purify the toxic wastewater created by controversial fracking plants, since the electrical current could theoretically be used to sterilize the fluid stream in addition to removing unwanted particles in the water source.

Research into shock electrodialysis so far has proved the theory of the technique and has demonstrated working process models. The next step in bringing shock electrodialsysis to real world desalination and water purification applications will require the design of a system developed specifically for practical testing on that scale. Bazant and his team don’t believe their system will compete with traditional desalination processes at the outset, but he does see the benefit of the alternative treatment system down the line. For example, the minimal infrastructure requirements of the shock electrodialsysis system would make it a portable, inexpensive solution for emergency situations or remote locations where supplies are limited.

Chloe Olewitz
Chloe is a writer from New York with a passion for technology, travel, and playing devil's advocate. You can find out more…
Digital Trends’ Top Tech of CES 2023 Awards
Best of CES 2023 Awards Our Top Tech from the Show Feature

Let there be no doubt: CES isn’t just alive in 2023; it’s thriving. Take one glance at the taxi gridlock outside the Las Vegas Convention Center and it’s evident that two quiet COVID years didn’t kill the world’s desire for an overcrowded in-person tech extravaganza -- they just built up a ravenous demand.

From VR to AI, eVTOLs and QD-OLED, the acronyms were flying and fresh technologies populated every corner of the show floor, and even the parking lot. So naturally, we poked, prodded, and tried on everything we could. They weren’t all revolutionary. But they didn’t have to be. We’ve watched enough waves of “game-changing” technologies that never quite arrive to know that sometimes it’s the little tweaks that really count.

Read more
Digital Trends’ Tech For Change CES 2023 Awards
Digital Trends CES 2023 Tech For Change Award Winners Feature

CES is more than just a neon-drenched show-and-tell session for the world’s biggest tech manufacturers. More and more, it’s also a place where companies showcase innovations that could truly make the world a better place — and at CES 2023, this type of tech was on full display. We saw everything from accessibility-minded PS5 controllers to pedal-powered smart desks. But of all the amazing innovations on display this year, these three impressed us the most:

Samsung's Relumino Mode
Across the globe, roughly 300 million people suffer from moderate to severe vision loss, and generally speaking, most TVs don’t take that into account. So in an effort to make television more accessible and enjoyable for those millions of people suffering from impaired vision, Samsung is adding a new picture mode to many of its new TVs.
[CES 2023] Relumino Mode: Innovation for every need | Samsung
Relumino Mode, as it’s called, works by adding a bunch of different visual filters to the picture simultaneously. Outlines of people and objects on screen are highlighted, the contrast and brightness of the overall picture are cranked up, and extra sharpness is applied to everything. The resulting video would likely look strange to people with normal vision, but for folks with low vision, it should look clearer and closer to "normal" than it otherwise would.
Excitingly, since Relumino Mode is ultimately just a clever software trick, this technology could theoretically be pushed out via a software update and installed on millions of existing Samsung TVs -- not just new and recently purchased ones.

Read more
AI turned Breaking Bad into an anime — and it’s terrifying
Split image of Breaking Bad anime characters.

These days, it seems like there's nothing AI programs can't do. Thanks to advancements in artificial intelligence, deepfakes have done digital "face-offs" with Hollywood celebrities in films and TV shows, VFX artists can de-age actors almost instantly, and ChatGPT has learned how to write big-budget screenplays in the blink of an eye. Pretty soon, AI will probably decide who wins at the Oscars.

Within the past year, AI has also been used to generate beautiful works of art in seconds, creating a viral new trend and causing a boon for fan artists everywhere. TikTok user @cyborgism recently broke the internet by posting a clip featuring many AI-generated pictures of Breaking Bad. The theme here is that the characters are depicted as anime characters straight out of the 1980s, and the result is concerning to say the least. Depending on your viewpoint, Breaking Bad AI (my unofficial name for it) shows how technology can either threaten the integrity of original works of art or nurture artistic expression.
What if AI created Breaking Bad as a 1980s anime?
Playing over Metro Boomin's rap remix of the famous "I am the one who knocks" monologue, the video features images of the cast that range from shockingly realistic to full-on exaggerated. The clip currently has over 65,000 likes on TikTok alone, and many other users have shared their thoughts on the art. One user wrote, "Regardless of the repercussions on the entertainment industry, I can't wait for AI to be advanced enough to animate the whole show like this."

Read more