“Water, drinking water everywhere, nor any fall to drink,” English poet Samuel Taylor Coleridge wrote of the anguish felt by sailors on becoming surrounded by undrinkable drinking water when faced with thirst.

More than 200 years later on, environmentalists have adopted Coleridge’s famed line in describing escalating drinking water shortages around the globe. David Cohen-Tanugi, a PhD student in supplies science and engineering at MIT, sees option in desalination, the elimination of salt and other minerals from saline drinking water to make it ideal for intake and use by individuals, which includes in agriculture.

“I’ve always been committed to the surroundings,” claims Cohen-Tanugi, a native of Paris, “but I had in no way definitely imagined of it as a career right before.”

David Cohen-Tanugi Picture: Allegra Boverman

As an undergraduate at Princeton College, Cohen-Tanugi examined physics and East Asian scientific tests. Curiously, he located drinking water technological innovation to be at the intersection of these two pursuits.

When at Princeton, Cohen-Tanugi had the option to are living in China on two distinctive occasions. The initial time was a summer season expended volunteering as an educator in rural China, teaching philosophy, French and physics. The next time, also all through a summer season, he worked for the Nationwide Methods Protection Council (NRDC) investigating the consequences of city scheduling on traffic congestion in Beijing. 

“There was anything about not observing the sunshine for virtually two months on stop, on account of all the smog, that created me realize that I didn’t want the relaxation of the earth to working experience that,” Cohen-Tanugi claims.

Through a subsequent take a look at to China, as an NRDC China Local climate Fellow doing the job to coordinate efforts in between the United States and China to tackle local weather change, he noticed that “China sees the likely in desalination … since they are becoming much more and much more sensitive to the worry of the deficiency of drinking water.” 

A new position for graphene

Obtaining noticed the world’s most populous nation positioning alone for innovation in the drinking water sector, Cohen-Tanugi started to see opportunities in desalination as nicely.

Considering the fact that enrolling at MIT in 2010 and doing the job with Jeffrey Grossman, the Carl Richard Soderberg Associate Professor of Electricity Engineering, Cohen-Tanugi’s concentration has develop into engineering greater filters or membranes to purify saline drinking water.

“The greater your membrane, the much less power you will consume in the course of action,” Cohen-Tanugi claims. “The thinner the membrane, the much more drinking water will go through and aid with performance of the desalination plant.”

Using personal computer simulations, Cohen-Tanugi has experimented with graphene: a very slim, nonetheless strong, product whose compact pores can be “tuned” to permit much more drinking water in, although continue to blocking impurities. These very small nanopores, developed employing procedures this kind of as chemical etching and hydrogen ion beam drilling, could actually switch graphene into an ultrasensitive filtration instrument. In contrast to present-day polyamide-based mostly filters, graphene filters could greatly lower both of those the amount of money of salt in drinking water and the power expected for desalination.

When graphene has been made use of thoroughly in electronics, Cohen-Tanugi claims there has been minimal do the job on graphene-based mostly filters for use in desalination. The moment the efficacy of these graphene filters has been set up, Cohen-Tanugi hopes that they may possibly be included to desalination amenities like the a single underneath construction in San Diego that will rank, on its completion, as the premier in the Western Hemisphere.

“The thought behind this kind of filters is that a major plant will do the preliminary treatment of saline drinking water and then it will go to normal drinking water amenities for distribution,” he claims. 

Influenced by Israel

As portion of his investigate on desalination, Cohen-Tanugi was portion of an MIT Worldwide Science and Know-how Initiatives (MISTI) excursion final December to Israel, the place he learned much more about how that state places desalination technological innovation to use.

“They depend a lot on desalination and have alleviated a lot of their drinking water problems,” Cohen-Tanugi claims. “They do not consider on their own in a long-lasting drinking water crisis anymore, and a lot of it has to do with their infrastructure publish-drinking water treatment.”

For case in point, Cohen-Tanugi describes how roadside flora is irrigated in Israel: “The trees had a community of pipes around their base that would feed them with drinking water that had been dealt with. It wasn’t a sprinkler that aimed in a basic way or even a human being who watered it, but a very concentrated, conservative program that stored the tree watered.”

There is continue to the issue of the amount of money of power that desalination demands, which is yet another avenue to consider, according to Cohen-Tanugi. “Desalination has only been around for about 50 years, and there is considerably place for enhancement,” he claims.

Cohen-Tanugi also serves as the president of the MIT Drinking water Club, a community of people today who are doing the job in the drinking water sector. “We deliver collectively college students, researchers, traders, persons from the plan stop and business people to converse about drinking water challenges,” Cohen-Tanugi claims. “It allows link persons from distinctive fields to tackle the problems of a widespread useful resource.”

Cohen-Tanugi hopes, on completing his PhD in about two years, to come across a posture the place he can carry on to implement technological insights to environmental challenges — as nicely as a way of engaging his fascination with East Asia.