U of Illinois & Ben-Gurion U Create ‘Ultra’ Filtration Membranes that remove viruses from drinking water


 

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Current membrane filtration methods require intensive energy to adequately remove pathogenic viruses without using chemicals like chlorine, which can contaminate the water with disinfection byproducts. Researchers at UIUC and BGU collaborated on the new approach for virus pathogen removal, which was published in the current issue of Water Research.

“This is an urgent matter of public safety,” the researchers say. “Insufficient removal of human Adenovirus in municipal wastewater, for example, has been detected as a contaminant in U.S. drinking water sources, including the Great Lakes and worldwide.”

Researchers from Ben-Gurion University of the Negev (BGU) and the University of Illinois at Urbana-Champaign (UIUC) have developed novel ultrafiltration membranes that significantly improve the virus-removal process from treated municipal wastewater used for drinking in water-scarce cities (Water Research, “Improvement of virus removal using ultrafiltration membranes modified with grafted zwitterionic polymer hydrogels”).

The norovirus, which can cause nausea, vomiting and diarrhea, is the most common cause of viral gastroenteritis in humans, and is estimated to be the second leading cause of gastroenteritis-associated mortality. Human adenoviruses can cause a wide range of illnesses that include the common cold, sore throat (pharyngitis), bronchitis, pneumonia, diarrhea, pink eye (conjunctivitis), fever, bladder inflammation or infection (cystitis), inflammation of the stomach and intestines (gastroenteritis), and neurological disease.

 

In the study, Prof. Moshe Herzberg of the Department of Desalination and Water Treatment in the Zuckerberg Institute for Water Research at BGU and his group grafted a special hydrogel coating onto a commercial ultrafiltration membrane. The “zwitterionic polymer hydrogel” repels the viruses from approaching and passing through the membrane. It contains both positive and negative charges and improves efficiency by weakening virus accumulation on the modified filter surface. The result was a significantly higher rate of removal of waterborne viruses, including human norovirus and adenovirus.Nanofiltration II Membrane-Layers-01

 

“Utilizing a simple graft-polymerization of commercialized membranes to make virus removal more comprehensive is a promising development for controlling filtration of pathogens in potable water reuse,” says Prof. Nguyen, Department of Chemical Engineering, UIUC.
Source: American Associates, Ben-Gurion University of the Negev

 

Researchers develop hybrid nuclear desalination technique with improved efficiency


3-newtechnologAssociate Professor I.M. Kurchatov and graduate student R.A. Alexandrov work at the research stand of water purification. Credit: National Research Nuclear University

Lack of fresh water requires development of new desalination methods, including advanced nuclear desalination and water treatment and recycling; requirements for drinking water and other uses may be different.Desal-Hadera--Israel-2

 

To improve environmental safety and desalination technology, it is necessary to solve a global scientific and technological problem—the creation of an integrated water supply system based on the use of new high-efficiency desalination methods such as nuclear membrane desalination or hybrid technologies. These methods should be combined with recycling and treatment of residues to a level that corresponds with environmental requirements.

The majority of modern desalination technologies are based on distillation of thermal energy, including nuclear desalination, or using desalination membranes (reverse osmosis and electrodialysis membranes). In the process of distillation, salt water is boiled, and produced steam leaves the system and is condensed as fresh water. If a nuclear reactor is used as the heat source, the method is called nuclear desalination.

The membrane method of reverse osmosis is based on the filtering of salt water under the influence of differential pressure across a semipermeable membrane allowing water molecules and excluding salts; the pressure differential should be more than the so-called osmotic pressure (~ 30 atm. for seawater). In membrane electrodialysis, ions penetrate through the so-called ion-exchange membranes, and fresh water remains in the channel.

These membrane methods can be used in conjunction with nuclear desalination (hybrid desalination technologies), i.e., they can be added to existing nuclear facilities, where there is a relatively cheap access to thermal energy.

For the normal functioning of desalination plants, quality of the source water must meet certain strict requirements. This entails the need for a pre-treatment system, the cost of which is sometimes two to three times more than the cost of the itself.

Scientists from the National Research Nuclear University MEPhI (Russia) have developed a new technology and technological schemes for a pretreatment unit taking into account data on the composition of pollutants, salinity and performance of water treatment systems. It is based on the reagent methods with hydrodynamic activation of the process of pollutant withdrawal in coagulation, flocculation and adsorption, which reduces the unit’s size and cost. Moreover, the majority of the sparingly soluble salts can be removed in the pretreatment unit, which increases the efficiency of the system as a whole.

From the pre-water treatment unit, salt water flows into the desalination unit, a very energy-intensive process. Hybrid desalination schemes are proposed to reduce the energy consumption of the desalination process. These schemes use distillation and membrane methods in combination, to produce both drinking water and process water.

In addition, the project proposes the development of an integrated technological system of recycling and desalination systems to reduce environmental burdens and improve the energy efficiency of the system as a whole.

The results are intended to be used in complex projects of the State Corporation Rosatom, in particular, in relation to nuclear power plants in Egypt, where it is planned to realize a nuclear technology.

Explore further: Drinking water from the sea using solar energy

 

Turning Seawater into Drinking Water ~ Graphene Sieves May Hold the Key


Graphene Seives 58e264acaef12A graphene membrane. Credit: The University of Manchester

 

“By 2025 the UN expects that 14% of the world’s population will encounter water scarcity.”

Graphene-oxide membranes have attracted considerable attention as promising candidates for new filtration technologies. Now the much sought-after development of making membranes capable of sieving common salts has been achieved.

New research demonstrates the real-world potential of providing for millions of people who struggle to access adequate clean water sources.

The new findings from a group of scientists at The University of Manchester were published today in the journal Nature Nanotechnology. Previously graphene-oxide membranes have shown exciting potential for gas separation and water filtration.

Graphene-oxide membranes developed at the National Graphene Institute have already demonstrated the potential of filtering out small nanoparticles, organic molecules, and even large salts. Until now, however, they couldn’t be used for sieving common salts used in technologies, which require even smaller sieves.

Previous research at The University of Manchester found that if immersed in water, graphene-oxide membranes become slightly swollen and smaller salts flow through the membrane along with water, but larger ions or molecules are blocked.

The Manchester-based group have now further developed these and found a strategy to avoid the swelling of the membrane when exposed to water. The in the membrane can be precisely controlled which can sieve common salts out of salty water and make it safe to drink.

As the effects of climate change continue to reduce modern city’s water supplies, wealthy modern countries are also investing in desalination technologies. Following the severe floods in California major wealthy cities are also looking increasingly to alternative water solutions.

WEF 2017 graphene-water-071115-rtrde3r1-628x330 (2)World Economic Forum: Can Graphene Make the World’s Water Clean?

 

 

 

 

When the common salts are dissolved in water, they always form a ‘shell’ of around the salts molecules. This allows the tiny capillaries of the graphene-oxide membranes to block the from flowing along with the water. Water molecules are able to pass through the membrane barrier and flow anomalously fast which is ideal for application of these membranes for desalination.

Professor Rahul Nair, at The University of Manchester said: “Realisation of scalable membranes with uniform pore size down to atomic scale is a significant step forward and will open new possibilities for improving the efficiency of desalination .

“This is the first clear-cut experiment in this regime. We also demonstrate that there are realistic possibilities to scale up the described approach and mass produce graphene-based membranes with required sieve sizes.”

Mr. Jijo Abraham and Dr. Vasu Siddeswara Kalangi were the joint-lead authors on the research paper: “The developed membranes are not only useful for desalination, but the atomic scale tunability of the pore size also opens new opportunity to fabricate membranes with on-demand filtration capable of filtering out ions according to their sizes.” said Mr. Abraham.

By 2025 the UN expects that 14% of the world’s population will encounter water scarcity. This technology has the potential to revolutionize water filtration across the world, in particular in countries which cannot afford large scale desalination plants.

It is hoped that graphene-oxide systems can be built on smaller scales making this technology accessible to countries which do not have the financial infrastructure to fund large plants without compromising the yield of fresh produced.

Explore further: Researchers develop hybrid nuclear desalination technique with improved efficiency

More information: Tunable sieving of ions using graphene oxide membranes, Nature Nanotechnology, nature.com/articles/doi:10.1038/nnano.2017.21

Reusable carbon nanotubes could be the water filter of the future, says RIT study


Carbon NT Water Filter 136842_web

 

A new class of carbon nanotubes could be the next-generation clean-up crew for toxic sludge and contaminated water, say researchers at Rochester Institute of Technology.

Enhanced single-walled carbon nanotubes offer a more effective and sustainable approach to water treatment and remediation than the standard industry materials–silicon gels and activated carbon–according to a paper published in the March issue of Environmental Science Water: Research and Technology.

RIT researchers John-David Rocha and Reginald Rogers, authors of the study, demonstrate the potential of this emerging technology to clean polluted water. Their work applies carbon nanotubes to environmental problems in a specific new way that builds on a nearly two decades of nanomaterial research. Nanotubes are more commonly associated with fuel-cell research.

Graphene Mem 050815 3-anewapproachAlso Read About: UC BERKELEY: NANOTECHNOLOGY CAN HELP DELIVER AFFORDABLE, CLEAN WATER WITH GRAPHENE MEMBRANE: VIDEO

 

 

“This aspect is new–taking knowledge of carbon nanotubes and their properties and realizing, with new processing and characterization techniques, the advantages nanotubes can provide for removing contaminants for water,” said Rocha, assistant professor in the School of Chemistry and Materials Science in RIT’s College of Science.

Rocha and Rogers are advancing nanotube technology for environmental remediation and water filtration for home use.

“We have shown that we can regenerate these materials,” said Rogers, assistant professor of chemical engineering in RIT’s Kate Gleason College of Engineering. “In the future, when your water filter finally gets saturated, put it in the microwave for about five minutes and the impurities will get evaporated off.”

Carbon nanotubes are storage units measuring about 50,000 times smaller than the width of a human hair. Carbon reduced to the nanoscale defies the rules of physics and operates in a world of quantum mechanics in which small materials become mighty.

“We know carbon as graphite for our pencils, as diamonds, as soot,” Rocha said. “We can transform that soot or graphite into a nanometer-type material known as graphene.”

A single-walled carbon nanotube is created when a sheet of graphene is rolled up. The physical change alters the material’s chemical structure and determines how it behaves. The result is “one of the most heat conductive and electrically conductive materials in the world,” Rocha said. “These are properties that only come into play because they are at the nanometer scale.”

The RIT researchers created new techniques for manipulating the tiny materials. Rocha developed a method for isolating high-quality, single-walled carbon nanotubes and for sorting them according to their semiconductive or metallic properties. Rogers redistributed the pure carbon nanotubes into thin papers akin to carbon-copy paper.

“Once the papers are formed, now we have the adsorbent–what we use to pull the contaminants out of water,” Rogers said.

The filtration process works because “carbon nanotubes dislike water,” he added. Only the organic contaminants in the water stick to the nanotube, not the water molecules.

“This type of application has not been done before,” Rogers said. “Nanotubes used in this respect is new.”

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Co-authors on the paper are Ryan Capasse, RIT chemistry alumnus, and Anthony Dichiara, a former RIT post-doctoral researcher in chemical engineering now at the University of Washington.

Harnessing the Transformative Possibilities of the “Nanoworld”


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Snow Crystal Landscape. Credit: Peter Gorges

Scientists have long suspected that the way materials behave on the nanoscale – that is when particles have dimensions of about 1–100 nanometres – is different from how they behave on any other scale. A new paper in the journal Chemical Science provides concrete proof that this is the case.

The laws of thermodynamics govern the behavior of materials in the macro world, while quantum mechanics describes behavior of particles at the other extreme, in the world of single atoms and electrons.

But in the middle, on the order of around 10–100,000 molecules, something different is going on. Because it’s such a tiny scale, the particles have a really big surface-area-to-volume ratio. This means the energetics of what goes on at the surface become very important, much as they do on the atomic scale, where is often applied.

Classical thermodynamics breaks down. But because there are so many particles, and there are many interactions between them, the quantum model doesn’t quite work either.

And because there are so many particles doing different things at the same time, it’s difficult to simulate all their interactions using a computer. It’s also hard to gather much experimental information, because we haven’t yet developed the capacity to measure behaviour on such a tiny scale.

This conundrum becomes particularly acute when we’re trying to understand crystallisation, the process by which particles, randomly distributed in a solution, can form highly ordered crystal structures, given the right conditions.

Chemists don’t really understand how this works. How do around 1018 molecules, moving around in solution at random, come together to form a micro- to millimetre size ordered crystal? Most remarkable perhaps is the fact that in most cases every crystal is ordered in the same way every time the crystal is formed.

However, it turns out that different conditions can sometimes yield different crystal structures. These are known as polymorphs, and they’re important in many branches of science including medicine – a drug can behave differently in the body depending on which polymorph it’s crystallised in.

What we do know so far about the process, at least according to one widely accepted model, is that particles in solution can come together to form a nucleus, and once a critical mass is reached we see crystal growth. The structure of the nucleus determines the structure of the final crystal, that is, which polymorph we get.Nanoparticle 2 051316 coated-nanoparticle

What we have not known until now is what determines the structure of the nucleus in the first place, and that happens on the nanoscale.

In this paper, the authors have used mechanochemistry – that is milling and grinding – to obtain nanosized , small enough that surface effects become significant. In other words, the chemistry of the nanoworld – which structures are the most stable at this scale, and what conditions affect their stability, has been studied for the first time with carefully controlled experiments.

And by changing the milling conditions, for example by adding a small amount of solvent, the authors have been able to control which polymorph is the most stable. Professor Jeremy Sanders of the University of Cambridge’s Department of Chemistry, who led the work, said “It is exciting that these simple experiments, when carried out with great care, can unexpectedly open a new door to understanding the fundamental question of how surface effects can control the stability of nanocrystals.”

Joel Bernstein, Global Distinguished Professor of Chemistry at NYU Abu Dhabi, and an expert in and structure, explains: “The authors have elegantly shown how to experimentally measure and simulate situations where you have two possible nuclei, say A and B, and determine that A is more stable. And they can also show what conditions are necessary in order for these stabilities to invert, and for B to become more stable than A.”

“This is really news, because you can’t make those predictions using classical thermodynamics, and nor is this the quantum effect. But by doing these experiments, the authors have started to gain an understanding of how things do behave on this size regime, and how we can predict and thus control it. The elegant part of the experiment is that they have been able to nucleate A and B selectively and reversibly.”

One of the key words of chemical synthesis is ‘control’. Chemists are always trying to control the properties of materials, whether that’s to make a better dye or plastic, or a drug that’s more effective in the body. So if we can learn to control how molecules in a solution come together to form solids, we can gain a great deal. This work is a significant first step in gaining that control.

Explore further: Surface chemistry offers new approach to directing crystal formation in pharmaceutical industry

More information: A. M. Belenguer et al. Solvation and surface effects on polymorph stabilities at the nanoscale, Chem. Sci. (2016). DOI: 10.1039/C6SC03457H

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Read Genesis Nanotechnology ~ Phantom Matter comes 2 Life+Graphene Super Caps 2 Power Tesla Rival Battery+NanoNeuro 2 treat stroke, epilepsy, Parkinson’s disease, cardiac conditions, and many others + ..http://buff.ly/2eCo78v

NSF and Stony Brook University: New Nanotechnology to produce sustainable, clean water for developing nations: Video


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This technology would enable communities to produce their own water filters using biomass nanofibers, making clean water more accessible and affordable.

The world’s population is projected to increase by 2-3 billion over the next 40 years. Already, more than three quarters of a billion people lack access to clean drinking water and 85 percent live in the driest areas of the planet. Those statistics are inspiring chemist Ben Hsiao and his team at Stony Brook University. With support from the National Science Foundation (NSF), the team is hard at work designing nanometer-scale water filters that could soon make clean drinking water available and affordable for even the poorest of the poor.

Traditional water filters are made of polymer membranes with tiny pores to filter out bacteria and viruses. Hsiao’s filters are made of fibers that are all tangled up, and the pores are the natural gaps between the strands. The team’s first success at making the new nanofilters uses a technique called electrospinning to produce nanofibers under an electrical field.

Hsiao’s team is also looking to cut costs even further by using “biomass” nanofibers extracted from trees, grasses, shrubs — even old paper. Hsiao says it will be a few years yet before the environmentally friendly biomass filters are ready for widespread use in developing countries, but the filters will eliminate the need to build polymer plants in developing areas. Ultimately, those filters could be produced locally with native biomass or biowaste.

The research in this episode was supported by NSF award #1019370, Breakthrough Concepts on Nanofibrous Membranes with Directed Water Channels for Energy-Saving Water Purification.

Watch the Video: New Nanotechnology to Produce Sustainable, Clean Drinking Water for Developing NationsSilver Nano P clean-drinking-water-india

NSF and Stony Brook University: New nanotechnology to produce sustainable, clean water for developing nations


This technology would enable communities to produce their own water filters using biomass nanofibers, making clean water more accessible and affordable – Follow the Link below to Watch the Video.

The world’s population is projected to increase by 2-3 billion over the next 40 years. Already, more than three quarters of a billion people lack access to clean drinking water and 85 percent live in the driest areas of the planet.

Those statistics are inspiring chemist Ben Hsiao and his team at Stony Brook University. With support from the National Science Foundation (NSF), the team is hard at work designing nanometer-scale water filters that could soon make clean drinking water available and affordable for even the poorest of the poor.

Traditional water filters are made of polymer membranes with tiny pores to filter out bacteria and viruses. Hsiao’s filters are made of fibers that are all tangled up, and the pores are the natural gaps between the strands. The team’s first success at making the new nanofilters uses a technique called electrospinning to produce nanofibers under an electrical field.

Hsiao’s team is also looking to cut costs even further by using “biomass” nanofibers extracted from trees, grasses, shrubs — even old paper. Hsiao says it will be a few years yet before the environmentally friendly biomass filters are ready for widespread use in developing countries, but the filters will eliminate the need to build polymer plants in developing areas. Ultimately, those filters could be produced locally with native biomass or biowaste.

The research in this episode was supported by NSF award #1019370, Breakthrough Concepts on Nanofibrous Membranes with Directed Water Channels for Energy-Saving Water Purification.Silver Nano P clean-drinking-water-india

Watch the Video Here: New Nanotechnology for Sustainable, Clean Water for Developing Nations

MIT: Seeking sustainable solutions through Nanotechnology – Engineer’s designs may help purify water, diagnose disease in remote regions of world.


mit-karnik-rohit-1“I try to guide my research by … asking myself the question, ‘What can we do today that will have a lasting impact and be conducive to a sustainable human civilization?’” says Rohit Karnik, an associate professor in MIT’s Department of Mechanical Engineering. Photo: Ken Richardson

In Rohit Karnik’s lab, researchers are searching for tiny solutions to some of the world’s biggest challenges.

In one of his many projects, Karnik, an associate professor in MIT’s Department of Mechanical Engineering, is developing a new microfluidic technology that can quickly and simply sorts cells from small samples of blood. The surface of a microfluidic channel is patterned to direct certain cells to roll toward a reservoir for further analysis, while allowing the rest of the blood sample to pass through. With this design, Karnik envisions developing portable, disposable devices that doctors may use, even in remote regions of the world, to quickly diagnose conditions ranging from malaria to sepsis.

Karnik’s group is also tackling issues of water purification. The researchers are designing filters from single layers of graphene, which are atom-thin sheets of carbon known for their exceptional strength. Karnik has devised a way to control the size and concentration of pores in graphene, and is tailoring single layers to filter out miniscule and otherwise evasive contaminants. The group has also successfully filtered salts using the technique and hopes to develop efficient graphene filters for water purification and other applications. Silver Nano P clean-drinking-water-india

In looking for water-purifying solutions, Karnik’s group also identified a surprisingly low-tech option: the simple tree branch. Karnik found that the pores within a pine branch that normally help to transport water up the plant are ideal for filtering bacteria from water. The group has shown that a peeled pine branch can filter out up to 99.00 percent of E. coli from contaminated water. Karnik’s group is building up on this work to explore the potential for simple and affordable wood-based water purification systems.

“I try to guide my research by long-term sustainability, in a specific sense, by asking myself the question, ‘What can we do today that will have a lasting impact and be conducive to a sustainable human civilization?’ Karnik says. “I try to align myself with that goal.”

From stargazer to tinkerer

Karnik was born and raised in Pune, India, which was then a relatively quiet city 100 miles east of Mumbai. Karnik describes himself while growing up as shy, yet curious about the way the world worked. He would often set up simple experiments in his backyard, seeing, for instance, how transplanting ants from one colony to another would change the ants’ behavior. (The short answer: They fought, sometimes to the death.) He developed an interest in astronomy early on and often explored the night sky with a small telescope, from the roof of his family’s home.

“I used to take my telescope up to the terrace in the middle of the night, which required three different trips up six or seven flights of stairs,” Karnik says. “I’d set the alarm for 3 a.m., go up, and do quite a bit of stargazing.”

That telescope would soon serve another use, as Karnik eventually found that, by inverting it and adding another lens, he could repurpose the telescope as a microscope.

“I built a little setup so I could look at different things, and I used to collect stuff from around the house, like onion peels or fungus growing on trees, to look at their cells,” Karnik says.

When it came time to decide on a path of study, Karnik was inspired by his uncle, a mechanical engineer who built custom machines “that did all kinds of things, from making concrete bricks, to winding up springs,” Karnik says. “What I saw in mechanical engineering was the ability to building something that integrates across different disciplines.”

Seeking balance and insight

As an entering student at the Indian Institute of Technology Bombay, Karnik chose to study mechanical engineering over electrical engineering, which was the more popular choice among students at the time. For his thesis, he looked for new ways to model three-dimensional cracks in materials such as steel beams.

Casting around for a direction after graduating, Karnik landed on the fast-growing field of nanotechnology. Arun Majumdar, an IIT alum and professor at the University of California at Berkeley, was studying energy conversion and biosensing in nanoscale systems. Karnik joined the professor’s lab as a graduate student, moving to California in 2002. For his graduate work, Karnik helped to develop a microfluidic platform to rapidly mix the contents of and test reactions occurring within droplets. He followed this work up with a PhD thesis in which he explored how fluid, flowing through tiny, nanometer-sized channels, can be controlled  to sense and direct ions and molecules.

Toward the end of his graduate work, Karnik interviewed for and ultimately accepted a faculty position at MIT. However, he was still completing his PhD thesis at Berkeley and had less than 4 years of experience beyond his bachelor’s degree. To help ease the transition, MIT offered Karnik an interim postdoc position in the lab of Robert Langer, the David H. Koch Institute Professor and a member of the Koch Institute for Integrative Cancer Research.

“It was an insightful experience,” Karnik remembers. “For a mechanical engineer who’s never been outside mechanical engineering, I basically had little experience how to do things in biology. It opened up possibilities for working with the biomedical community.”

When Karnik finally assumed his position as assistant professor of mechanical engineering in 2007, he experienced a tidal wave of deadlines, demands, and responsibilities — a common initiation for first-time faculty.

“By its nature the job is overwhelming,” Karnik says. “The trick is how to maintain balance and sanity and do the things you like, without being distracted by the busyness around you, in some sense.”

He says several things have helped him to handle and even do away with stress: walks, which he takes each day to work and around campus, as well as yoga and meditation.

“If you can see things the way they are, by clearing away the filters your mind puts in place, you can get a clear perspective, and there are a lot of insights that come through,” Karnik says.

Researchers Create Unique Hybrid Nanomaterials to Transform Dirty Water into Drinkable Water


Graphene Hybrid Water072916 NewsImage_34896An artist’s rendering of nanoparticle biofoam developed by engineers at Washington University in St. Louis. The biofoam makes it possible to clean water quickly and efficiently using nanocellulose and graphene oxide. (Photo credit: Washington University in St. Louis)

Recently, a team of researchers from Washington University in St. Louis have discovered a method to use graphene oxide sheets to convert dirty water into drinking water. This could easily become a worldwide game-changer.

“We hope that for countries where there is ample sunlight, such as India, you’ll be able to take some dirty water, evaporate it using our material, and collect fresh water,” said Srikanth Singamaneni, associate professor of mechanical engineering and materials science at the School of Engineering & Applied Science.

The new method integrates graphene oxide and bacteria-produced cellulose to create a bi-layered biofoam. A paper explaining the research can be found online in Advanced Materials.

The process is extremely simple. The beauty is that the nanoscale cellulose fiber network produced by bacteria has excellent ability move the water from the bulk to the evaporative surface while minimizing the heat coming down, and the entire thing is produced in one shot. The design of the material is novel here. You have a bi-layered structure with light-absorbing graphene oxide filled nanocellulose at the top and pristine nanocellulose at the bottom.

When you suspend this entire thing on water, the water is actually able to reach the top surface where evaporation happens. Light radiates on top of it, and it converts into heat because of the graphene oxide — but the heat dissipation to the bulk water underneath is minimized by the pristine nanocellulose layer. You don’t want to waste the heat; you want to confine the heat to the top layer where the evaporation is actually happening.

Srikanth Singamaneni, Associate Professor, Washington University

The bottom of the bi-layered biofoam has the cellulose, which acts as a sponge, sucking water up to the graphene oxide where fast evaporation occurs. The resulting fresh water found at the top of the sheet can be effortlessly collected.

The method used to form the bi-layered biofoam is also new.

The graphene oxide flakes are embedded into the layers of nanocellulose fibers, which are formed by the bacteria. Using the same method used by an oyster to make a pearl, the bacteria create these layers.

While we are culturing the bacteria for the cellulose, we added the graphene oxide flakes into the medium itself. The graphene oxide becomes embedded as the bacteria produce the cellulose. At a certain point along the process, we stop, remove the medium with the graphene oxide and reintroduce fresh medium. That produces the next layer of our foam. The interface is very strong; mechanically, it is quite robust.

Qisheng Jiang, Graduate Student, Washington University

The new biofoam is also very light and cost-efficient to make, thus making it a feasible tool for desalination and water purification.

“Cellulose can be produced on a massive scale,” Singamaneni said, “and graphene oxide is extremely cheap — people can produce tons, truly tons, of it. Both materials going into this are highly scalable. So one can imagine making huge sheets of the biofoam.”

“The properties of this foam material that we synthesized has characteristics that enhances solar energy harvesting. Thus, it is more effective in cleaning up water,” said Pratim Biswas, the Lucy and Stanley Lopata Professor and chair of the Department of Energy, Environmental and Chemical Engineering.

“The synthesis process also allows addition of other nanostructured materials to the foam that will increase the rate of destruction of the bacteria and other contaminants, and make it safe to drink. We will also explore other applications for these novel structures.”

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“It’s ALL .. About the WATER! 2 Maps that Show the next Potential Catastrophe Affecting the Middle East: Solving the World’s Water Crisis


World ME Water 070816 screen shot 2016-07-08 at 11.27.43 am

 

As sectarian strife spearheaded by ISIS convulses the Middle East, and tensions between Iran and Saudi Arabia only deepen, it is hard to imagine that a far more pressing concern could be threatening the region.

But a series of maps from the UN show that despite the awful suffering already occurring throughout the Middle East, things could always become significantly worse. The central issue that will affect the region, vast swathes of North and East Africa, and even Central Asia and China is the increasing strain on and lack of the world’s single most important resource — water.

The following map from the UN Water’s 2015 World Water Development Report shows the total amount of renewable water sources per capita available in each country in the world. In 2013, a number of countries — including regional heavyweights such as Saudi Arabia and Jordan — were facing absolute water scarcity.

Egypt, the most populous country in the Middle East, faced water scarcity, as did Syria and Sudan. In Sudan, the lack of water is believed to be one of the root causes of the continuing conflict in the Darfur region as various groups have continued to compete over the increasingly scarce resource.

And the UN predicts that water scarcity will only intensify. By 2030, UN Water predicts that the world will “face a 40% global water deficit under the business-as usual [sic]” scenario. This strain on water, unless proactively addressed, will only cause further inter- and intra-state conflicts.

Again, according to UN Water, “inter-state and regional conflicts may also emerge due to water scarcity and poor management structures. It is noteworthy that 158 of the world’s 263 transboundary water basins lack any type of cooperative management framework.”

Essentially, the world as it currently is will continue to face worse water crises. These crises will force states, or individuals within states, to go to extreme lengths to survive. And without significant frameworks in place, people may resort to conflict for survival.

The following map, from the UN World Water Development Report 2016, shows the proportion of renewable water resources that have already been withdrawn. The Middle East and Central Asia is again at significant risk, as the majority of countries in both regions have withdrawn more than 60% of their water resources.

World Water II 070816 screen shot 2016-07-08 at 11.26.27 am

 

 

Green nature landscape with planet Earth

 

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