Rapid Nano-filter for clean water: Australian researchers design a rapid nano-filter that cleans dirty water 100X faster than current technology


quickandnots
The new technology can filter drinking water 100 times faster than current tech. Credit: Free stock photo 

Australian researchers have designed a rapid nano-filter that can clean dirty water over 100 times faster than current technology.

Simple to make and simple to scale up, the technology harnesses naturally occurring nano-structures that grow on .

The RMIT University and University of New South Wales (UNSW) researchers behind the innovation have shown it can filter both heavy metals and oils from water at extraordinary speed.

RMIT researcher Dr. Ali Zavabeti said water contamination remains a significant challenge globally—1 in 9 people have no clean water close to home.

“Heavy  contamination causes serious health problems and children are particularly vulnerable,” Zavabeti said.

“Our new nano-filter is sustainable, environmentally-friendly, scalable and low cost.

“We’ve shown it works to remove lead and oil from water but we also know it has potential to target other common contaminants.

“Previous research has already shown the materials we used are effective in absorbing contaminants like mercury, sulfates and phosphates.

“With further development and commercial support, this new nano-filter could be a cheap and ultra-fast solution to the problem of .”

Quick and not-so-dirty: A rapid nano-filter for clean water
A liquid metal droplet with flakes of aluminium oxide compounds grown on its surface. Each 0.03mm flake is made up of about 20,000 nano-sheets stacked together. Credit: RMIT University

The liquid metal chemistry process developed by the researchers has potential applications across a range of industries including electronics, membranes, optics and catalysis.

“The technique is potentially of significant industrial value, since it can be readily upscaled, the liquid metal can be reused, and the process requires only short reaction times and low temperatures,” Zavabeti said.

Project leader Professor Kourosh Kalantar-zadeh, Honorary Professor at RMIT, Australian Research Council Laureate Fellow and Professor of Chemical Engineering at UNSW, said the liquid metal chemistry used in the process enabled differently shaped nano-structures to be grown, either as the atomically thin sheets used for the nano-filter or as nano-fibrous structures.

“Growing these materials conventionally is power intensive, requires high temperatures, extensive processing times and uses toxic metals. Liquid metal chemistry avoids all these issues so it’s an outstanding alternative.”

How it works

The groundbreaking technology is sustainable, environmentally-friendly, scalable and low-cost.

The researchers created an alloy by combining gallium-based liquid metals with aluminium.

When this alloy is exposed to water, nano-thin sheets of  compounds grow naturally on the surface.

These atomically thin layers—100,000 times thinner than a human hair—restack in a wrinkled fashion, making them highly porous.

Quick and not-so-dirty: A rapid nano-filter for clean water
Microscope image of nano-sheets, magnified over 11,900 times. Credit: RMIT University

This enables water to pass through rapidly while the aluminium oxide compounds absorbs the contaminants.

Experiments showed the nano-filter made of stacked atomically thin sheets was efficient at removing lead from water that had been contaminated at over 13 times safe drinking levels, and was highly effective in separating oil from water.

The process generates no waste and requires just aluminium and , with the liquid metals reused for each new batch of nano-structures.

The method developed by the researchers can be used to grow nano-structured materials as ultra-thin sheets and also as nano-fibres.

These different shapes have different characteristics—the ultra-thin sheets used in the nano-filter experiments have high mechanical stiffness, while the nano-fibres are highly translucent.

The ability to grow materials with different characteristics offers opportunities to tailor the shapes to enhance their different properties for applications in electronics, membranes, optics and catalysis.

The research is funded by the Australian Research Council Centre for Future Low-Energy Electronics Technologies (FLEET).

The findings are published in the journal Advanced Functional Materials.

 Explore further: Liquid metal discovery ushers in new wave of chemistry and electronics

More information: Advanced Functional Materials (2018). DOI: 10.1002/adfm.201804057

 

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Australian scientists develop nanotechnology to purify water


Scientists in Australia have developed a ground-breaking new way to strip impurities from waste water, with the research set to have massive applications for a number of industries.

Scientists in Australia have developed a ground-breaking new way to strip impurities from waste water, with the research set to have massive applications for a number of industries.

By using a new type of crystalline alloy, researchers at Edith Cowan University (ECU) are able to extract the contaminants and pollutants that often end up in water during industrial processing.

“Mining and textile production produces huge amounts of waste water that is contaminated with heavy metals and dyes,” lead researcher Associate Professor Laichang Zhang from ECU’s School of Engineering technology said in a statement on Friday.

Although it is already possible to treat waste water with iron powder, according to Zhang, the cost is very high.

“Firstly, using iron powder leaves you with a large amount of iron sludge that must be stored and secondly it is expensive to produce and can only be used once,” he explained.

We can produce enough crystalline alloy to treat one tonne of waste water for just 15 Australian Dollars (10.8 US dollars), additionally, we can reuse the crystalline alloy up to five times while still maintaining its effectiveness.” Based on his previous work with “metal glass,” Zhang updated the nanotechnology to make it more effective.

“Whereas metallic glasses have a disordered atomic structure, the crystalline alloy we have developed has a more ordered atomic structure,” he said.

“We produced the crystalline alloy by heating metallic glass in a specific way.””This modifies the structure, allowing the electrons in the crystalline alloy to move more freely, thereby improving its ability to bind with dye molecules or heavy metals leaving behind usable water.”Zhang said he will continue to expand his research with industry partners to further improve the technology.

Rice University engineers develop system to remove contaminants from water


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Engineer Qilin Li at Rice University’s lab is building a treatment system that can be tuned to selectively pull toxins from wastewater from factories, sewage systems and oil and gas wells, as well as drinking water. The researchers said their technology will cut costs and save energy compared to conventional systems.

“Traditional methods to remove everything, such as reverse osmosis, are expensive and energy intensive,” said Li, the lead scientist and co-author of a study about the new technology in the American Chemical Society journal Environmental Science & Technology. “If we figure out a way to just fish out these minor components, we can save a lot of energy.”

The heart of Rice’s system is a set of novel composite electrodes that enable capacitive deionization. The charged, porous electrodes selectively pull target ions from fluids passing through the maze-like system. When the pores get filled with toxins, the electrodes can be cleaned, restored to their original capacity and reused.

“This is part of a broad scope of research to figure out ways to selectively remove ionic contaminants,” said Li, a professor of civil and environmental engineering and of materials science and nanoengineering. “There are a lot of ions in water. Not everything is toxic. For example, sodium chloride (salt) is perfectly benign. We don’t have to remove it unless the concentration gets too high.”

In tests, an engineered coating of resin, polymer and activated carbon removed and trapped harmful sulfate ions, and other coatings can be used in the same platform to target other contaminants. Illustration by Kuichang Zuo

The proof-of-principal system developed by Li’s team removed sulfate ions. The system’s electrodes were coated with activated carbon, which was in turn coated by a thin film of tiny resin particles held together by quaternized polyvinyl alcohol. When sulfate-contaminated water flowed through a channel between the charged electrodes, sulfate ions were attracted by the electrodes, passed through the resin coating and stuck to the carbon. Tests in the Rice lab showed the positively charged coating on the cathode preferentially captured sulfate ions over salt at a ratio of more than 20 to 1. The electrodes retained their properties over 50 cycles. “But in fact, in the lab, we’ve run the system for several hundred cycles and I don’t see any breaking or peeling of the material,” said Kuichang Zuo, lead author of the paper and a postdoctoral researcher in Li’s lab. “It’s very robust.”

In Rice’s new water-treatment platform, electrode coatings can be swapped out to allow the device to selectively remove a range of contaminants from wastewater, drinking water and industrial fluids. Illustration by Kuichang Zuo

“The true merit of this work is not that we were able to selectively remove sulfate, because there are many other contaminants that are perhaps more important,” she said. “The merit is that we developed a technology platform that we can use to target other contaminants as well by varying the composition of the electrode coating.”

The research was supported by the Rice-based National Science Foundation-backed Center for Nanotechnology-Enabled Water Treatment, the Welch Foundation and the Shanghai Municipal International Cooperation Foundation.

Nidec Motor Corp. appoints CEO

Nidec Motor Corporation (NMC) named Henk van Duijnhoven as its CEO and global business leader of ACIM (Appliances, Commercial and Industrial Motors). Van Duijnhoven was most recently a partner and managing director of The Boston Consulting Group where he was responsible for business turnaround, mergers and acquisitions, and strategy planning for clients in the industrial and medtech markets. He holds a Bachelor of Science degree from the College of Automotive Engineering and a Master of Business Administration from the Massachusetts Institute of Technology.

Woodard & Curran names new business unit leader

Woodard & Curran named Peter Nangeroni as its new industrial and commercial strategic business unit leader. He brings experience managing large, multidisciplinary projects for industrial clients with emphasis on generating positive environmental outcomes, return on investment and improved risk management. He has been with Woodard & Curran for 13 years in various roles, most recently as director of technical practices. He takes over for the long-time leader of the business unit, Mike Curato, who is retiring after 11 years in the role and 20 with the firm.

Nangeroni is a Professional Engineer with a degree in civil engineering from Tufts University and more than 35 years of experience working with clients on engineering and construction management projects. In his new role, he will oversee staffing, business development and project execution at a strategic level for the industrial and commercial strategic business unit, which focuses on water treatment, manufacturing and process utilities for clients in a wide range of industrial sectors.

Canadian Nanotechnology Firm Finds Water in the Driest of Air


A Canadian startup could have a new breakthrough in pulling moisture from the driest of places. For years, researchers around the world have been looking for new technology and methods of making drinkable water out of the atmosphere.

The company Awn Nanotech, based out of Montreal, have been leveraging the latest in nanotechnology to make that water harvesting a reality. Awn Nanotech, most recently, released new information about their progress at the American Physical Society’s March meeting — the world’s largest gathering of physicists.

Founder Richard Boudreault made the presentation, who is both a physicist and an entrepreneur with a sizeable number of other tech-based startup companies under his belt. He said the company got its inspiration after hearing about the water crises in southern California and South Africa. While most others were looking to solve the problem by desalination techniques and new technologies, he wanted to look to the sky instead.

He also wondered if he could create a more cost-efficient alternative to the other expensive options on the market. By tapping into nanotechnology, he could pull the particles toward each other and use the natural tension found in the surface as a force of energy to power the nanotechnology itself.

“It’s extremely simple technology, so it’s extremely durable,” Boudreault said at the press conference.

Boudreault partnered with college students throughout Canada to develop a specific textile. The fine mesh of carbon nanotubes would be both hydrophilic (attracts water to the surface) on one side and hydrophobic (repels water away from the surface) on the other.

Water particles hit the mesh and get pushed through the film from one side to the other. This ultimately forms droplets.

“Because of the surface tension, (the water) finds its way through,” Boudreault explained. The water then gets consolidated into storage tanks as clean water where it can await consumption. While there’s no need for power with the system, the Awn Nanotech team realized they could significantly speed up the water harvesting process by adding a simple fan. The team quickly added a small fan of a size that cools a computer. To make sure the fan also kept energy usage low, the fan itself runs on a small solar panel.

There have been some other attempts around the world to scale up water harvesting technology. In April 2017, a team from MIT partnered with University of California at Berkeley to harvest fog. They turned their attention to already very moist air and created a much cheaper alternative to other fog-harvesting methods using metal-organic frameworks.

However, unlike the small frameworks developed by the MIT researchers, Boudreault said that they’ve quickly scaled up their technology. In fact, the Awn Nanotech team has already created a larger alternative to their smaller scale that can capture 1,000 liters in one day. They’re currently selling their regular-scale water capture systems for $1,000 each, but the company intends on partnering with agricultural companies and farms for the more extensive systems.

Eco-Friendly Desalination using MOF’s could Supply the Lithium needed to Manufacture Batteries required to Mainstream EV’s


A new water purification (desalination) technology could be the key to more electric cars. How?

“Eco-Friendly Mining” of world’s the oceans for the vast amounts of lithium required for EV batteries, could “mainstream” our acceptance (affordability and accessibility) of Electric Vehicles and provide clean water – forecast to be in precious short supply in many parts of the World in the not so distant future.

energy_storage_2013-042216-_11-13-1Humanity is going to need a lot of lithium batteries if electric cars are going to take over, and that presents a problem when there’s only so much lithium available from conventional mines.

A potential solution is being researched that turns the world’s oceans into eco-friendly “Lithium supply mines.”

Scientists have outlined a desalination technique that would use metal-organic frameworks (sponge-like structures with very high surface areas) with sub-nanometer pores to catch lithium ions while purifying ocean water.

The approach mimics the tendency of cell membranes to selectively dehydrate and carry ions, leaving the lithium behind while producing water you can drink.

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While the concept of extracting lithium from our oceans certainly isn’t new, this new technology method would be much more efficient and environmentally friendly.

Instead of tearing up the landscape to find mineral deposits, battery makers would simply have to deploy enough filters.

It could even be used to make the most of water when pollution does take place — recovering lithium from the waste water at shale gas fields.

This method will require more research and development before it’s ready for real-world use.

However, the implications are already clear. If this desalination approach reaches sufficient scale, the world would have much more lithium available for electric vehicles, phones and other battery-based devices. It would also reduce the environmental impact of those devices. storedot-ev-battery-21-889x592 (1)

While some say current lithium mining practices negates some of the eco-friendliness of an EV, this “purification for Lithium” approach could let you drive relatively guilt-free

Reposted from Jonathan Fingas – Engadget

Toward a smart graphene membrane to desalinate water: Penn State University


Graphene H2O towardasmartA scalable graphene-based membrane for producing clean water Credit: Aaron Morelos-Gomez. Credit: Pennsylvania State University

An international team of researchers, including scientists from Shinshu University (Japan) and the director of Penn State’s ATOMIC Center, has developed a graphene-based coating for desalination membranes that is more robust and scalable than current nanofiltration membrane technologies. The result could be a sturdy and practical membrane for clean water solutions as well as protein separation, wastewater treatment and pharmaceutical and food industry applications.

“Our dream is to create a smart  that combines high flow rates, high efficiency, long lifetime, self-healing and eliminates bio and inorganic fouling in order to provide clean water solutions for the many parts of the world where clean water is scarce,” says Mauricio Terrones, professor of physics, chemistry and materials science and engineering, Penn State. “This work is taking us in that direction.”

The hybrid membrane the team developed uses a simple spray-on technology to coat a mixture of graphene oxide and few-layered graphene in solution onto a backbone support membrane of polysulfone modified with polyvinyl alcohol. The support membrane increased the robustness of the hybrid membrane, which was able to stand up to intense cross-flow, high pressure and chlorine exposure. Even in early stages of development, the membrane rejects 85 percent of salt, adequate for agricultural purposes though not for drinking, and 96 percent of dye molecules. Highly polluting dyes from textile manufacturing is commonly discharged into rivers in some areas of the world.

Chlorine is generally used to mitigate biofouling in membranes, but chlorine rapidly degrades the performance of current polymer membranes. The addition of few-layer graphene makes the new membrane highly resistant to chlorine.

Graphene is known to have high mechanical strength, and porous graphene is predicted to have 100 percent salt rejection, making it a potentially ideal material for desalination membranes. However, there are many challenges with scaling up graphene to industrial quantities including controlling defects and the need for complex transfer techniques required to handle the two-dimensional material. The current work attempts to overcome the scalability issues and provide an inexpensive, high quality membrane at manufacturing scale.

The work was performed in the Global Aqua Innovation Center and the Institute of Carbon Science and Technology at Shinshu University, Nagano, Japan, where Terrones is also a Distinguished Invited Professor. The team includes researchers Aaron Morelos-Gomez, Josue Ortiz-Medina and Rodolfo Cruz-Silva, former Ph.D. students of Terrones. Morelos-Gomez is lead author on a paper published online on August 28 in Nature Nanotechnology describing their work titled “Effective NaCL and dye rejection of hybrid graphene oxide/graphene layered membranes.” The Japanese researchers, Hiroyuki Muramatsu, Takumi Araki, Tomoyuki Fukuyo, Syogo Tejima, Kenji Takeuchi, and Takuya Hayashi, were also led by Professor Morinobu Endo.

First author Aaron Morelos-Gomez says, “Our membrane overcomes the water solubility of graphene oxide by using polyvinyl alcohol as an adhesive making it resistant against strong water flow and high pressures. By mixing  with  we could also improve significantly its chemical resistance.”

Professor Morinobu Endo concludes that “this is the first step towards more effective and smart membranes that could self-adapt depending on their environment.”

 Explore further: Graphene sieve turns seawater into drinking water

More information: Aaron Morelos-Gomez et al. Effective NaCl and dye rejection of hybrid graphene oxide/graphene layered membranes, Nature Nanotechnology (2017). DOI: 10.1038/nnano.2017.160

Read more at: https://phys.org/news/2017-09-smart-graphene-membrane-desalinate.html#jCp

Read more at: https://phys.org/news/2017-09-smart-graphene-membrane-desalinate.html#jCp

U of Pennsylvania: Large Scale Production of Graphene + Graphene Updates and Videos


Graphene Mem 050815 3-anewapproach
Draw a line with a pencil and it’s likely that somewhere along that black smudge is a material that earned two scientists the 2010 Nobel Prize in Physics. The graphite of that pencil tip is simply multiple layers of carbon atoms; where those layers are only one atom thick, it is known as graphene.

The properties of a material change at the nanoscopic scale, making graphene the strongest and most conductive substance known. Instead of marking mini-golf scores on paper, this form of carbon is suited for making faster and smaller electronic circuitry, flexible touchscreens, chemical sensors, diagnostic devices, and applications yet to be imagined.

Graphene is not yet as ubiquitous as plastic or silicon, however, and producing the material in bulk remains a challenge. Because graphene’s properties rely on it being only one atom thick, until recently, it was only possible to make it in small patches or flakes.

Physicists at Penn have discovered a way around these limitations, and have spun out their research into a company called Graphene Frontiers. Graphene Frontiers

 


More About Graphene

Turning saltwater into clean drinking water is an expensive, energy-intensive process, but could the wonder material graphene make it more accessible?

New Discovery Could Unlock Graphene’s Full Potential – 


Read More:

3D GrapheneFollow this direct link to Seeker.com for more information and Videos about the ‘Wonder Material’ of Graphene.

Seeker.com



Graphene sieve turns seawater into drinking water

“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 clean drinking water 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.”

MIT Researchers develop new (low energy) way to Clear Pollutants from Water: w/ Video


MIT-PurifyingWater-1_0Researchers have developed a new method for removing even extremely low levels of unwanted compounds from water. The new method relies on an electrochemical process to selectively remove organic contaminants such as pesticides, chemical waste products, and pharmaceuticals. Photo: Melanie Gonick/MIT

Electrochemical method can remove even tiny amounts of contamination.

When it comes to removing very dilute concentrations of pollutants from water, existing separation methods tend to be energy- and chemical-intensive. Now, a new method developed at MIT could provide a selective alternative for removing even extremely low levels of unwanted compounds.

The new approach is described in the journal Energy and Environmental Science, in a paper by MIT postdoc Xiao Su, Ralph Landau Professor of Chemical Engineering T. Alan Hatton, and five others at MIT and at the Technical University of Darmstadt in Germany.

The system uses a novel method, relying on an electrochemical process to selectively remove organic contaminants such as pesticides, chemical waste products, and pharmaceuticals, even when these are present in small yet dangerous concentrations. The approach also addresses key limitations of conventional electrochemical separation methods, such as acidity fluctuations and losses in performance that can happen as a result of competing surface reactions. Watch the Video:

Current systems for dealing with such dilute contaminants include membrane filtration, which is expensive and has limited effectiveness at low concentrations, and electrodialysis and capacitive deionization, which often require high voltages that tend to produce side reactions, Su says. These processes also are hampered by excess background salts.

In the new system, the water flows between chemically treated, or “functionalized,” surfaces that serve as positive and negative electrodes. These electrode surfaces are coated with what are known as Faradaic materials, which can undergo reactions to become positively or negatively charged. These active groups can be tuned to bind strongly with a specific type of pollutant molecule, as the team demonstrated using ibuprofen and various pesticides. The researchers found that this process can effectively remove such molecules even at parts-per-million concentrations.

Previous studies have usually focused on conductive electrodes, or functionalized plates on just one electrode, but these often reach high voltages that produce contaminating compounds. By using appropriately functionalized electrodes on both the positive and negative sides, in an asymmetric configuration, the researchers almost completely eliminated these side reactions. Also, these asymmetric systems allow for simultaneous selective removal of both positive and negative toxic ions at the same time, as the team demonstrated with the herbicides paraquat and quinchlorac.

The same selective process should also be applied to the recovery of high-value compounds in a chemical or pharmaceutical production plant, where they might otherwise be wasted, Su says. “The system could be used for environmental remediation, for toxic organic chemical removal, or in a chemical plant to recover value-added products, as they would all rely on the same principle to pull out the minority ion from a complex multi-ion system.”

The system is inherently highly selective, but in practice it would likely be designed with multiple stages to deal with a variety of compounds in sequence, depending on the exact application, Su says. “Such systems might ultimately be useful,” he sugggests, “for water purification systems for remote areas in the developing world, where pollution from pesticides, dyes, and other chemicals are often an issue in the water supply. The highly efficient, electrically operated system could run on power from solar panels in rural areas for example.”

Unlike membrane-based systems that require high pressures, and other electrochemical systems that operate at high voltages, the new system works at relatively benign low voltages and pressures, Hatton says. And, he points out, in contrast to conventional ion exchange systems where release of the captured compounds and regeneration of the adsorbents would require the addition of chemicals, “in our case you can just flip a switch” to achieve the same result by switching the polarity of the electrodes.

The research team has already racked up a series of honors for the ongoing development of water treatment technology, including grants from the J-WAFS Solutions and Massachusetts Clean Energy Catalyst competitions, and the researchers were the top winners last year’s MIT Water Innovation Prize. The researchers have applied for a patent on the new process. “We definitely want to implement this in the real world,” Hatton says. In the meantime, they are working on scaling up their prototype devices in the lab and improving the chemical robustness.

This technique “is highly significant, as it extends the capabilities of electrochemical systems from basically nonselective toward highly selective removal of key pollutants,” says Matthew Suss, an assistant professor of mechanical engineering at Technion Institute of Technology in Israel, who was not involved in this work. “As with many emerging water purification techniques, it must still must be tested under real-world conditions and for long periods to check durability. However, the prototype system achieved over 500 cycles, which is a highly promising result.”

These researchers “have systematically explored a variety of device configurations and a variety of contaminants,” says Kyle Smith, a professor of mechanical science and engineering at the University of Illinois, who also was not involved in this work. “In the process they have identified general design principles by which to achieve selective removal of contaminants. In this regard, I find Hatton and co-workers’ study to be very thorough and thoughtful. It provides a framework or paradigm for other researchers to emulate.” But, he adds, “A significant challenge that remains is the scale-up of these technologies.”

The team also included Kai-Jher Tan, Johannes Elbert, and Robert R. Taylor Professor of Chemistry Timothy Jamison at MIT; and Christian Ruttiger and Markus Gallei at the Technical University of Darmstadt. The work was supported by a seed grant from the Abdul Latif Jameel World Water and Food Security Lab (J-WAFS) at MIT.

New water filtration process uses 1,000 times less energy


New research could transform how we filter water Credit: University of Limerick

A new process for water filtration using carbon dioxide consumes one thousand times less energy than conventional methods, scientific research published recently has shown.

The research was led by Dr Orest Shardt of University of Limerick, Ireland together with Dr Sangwoo Shin (now at University of Hawaii, Manoa), while they were post doctoral researchers at Princeton University (United States) last year.

With global demand for clean water increasing, there is a continuing need to improve the performance of water treatment processes. Dr Shardt expects this new method which uses CO2 could be applied in a variety of industries such as mining, food and beverage production, pharmaceutical manufacturing and water treatment.

The research, published in open-access scientific journal Nature Communications, indicates that the new process could be easily scaled up, “suggesting the technique could be particularly beneficial in both the developing and developed worlds”. 
The new method could also be used to remove bacteria and viruses without chlorination or ultraviolet treatment.

“We are at the early stages of developing this concept. Eventually, this new method could be used to clean water for human consumption or to treat effluent from industrial facilities,” Dr Shardt stated.

Currently, water filtration technologies such as microfiltration or ultrafiltration use porous membranes to remove suspended particles and solutes. 

These processes trap and remove suspended particles, such as fine silt, by forcing the suspension through a porous material with gaps that are smaller than the particles. 
Energy must be wasted to overcome the friction of pushing the water through these small passages. These kinds of filtration processes have drawbacks such as high pumping costs and a need for periodic replacement of the membranes due to fouling. 

The research by Drs Shardt and Shin demonstrates an alternative membraneless method for separating suspended particles that works by exposing the colloidal suspension to CO2.

“The demonstration device is made from a standard silicone polymer, a material that is commonly used in microfluidics research and similar to what is used in household sealants. 

While we have not yet analysed the capital and operating costs of a scaled-up process based on our device, the low pumping energy it requires, just 0.1% that of conventional filtration methods, suggests that the process deserves further research,” said Dr Shardt.

“What we need to do now is to study the effects of various compounds, such as salts and dissolved organic matter that are present in natural and industrial water to understand what impact they will have on the process. 

This could affect how we optimise the operating conditions, design the flow channel, and scale-up the process,” he continued.

Since joining the €86 million Bernal Institute at University of Limerick last September, Dr Shardt is continuing his research on the mathematical modelling and simulation of the water purification process and the physical phenomena on which it is based.


“As a new arrival to Ireland,
I’m now looking for motivated PhD students to work with me in this area. I am sure that creative students will find new ways to improve the process and apply it in unexpected ways,” Dr Shardt concluded.

More information: Sangwoo Shin et al, Membraneless water filtration using CO2, 

Nature Communications (2017). DOI: 10.1038/ncomms15181

Provided by: University of Limerick

Turning Saltwater N2 Clean drinking Water ~ Graphene Could Solve the World’s Water Crisis: Video


Graphene Desal 1-simulationsp

Published on Apr 29, 2017

Turning  saltwater into clean drinking water is an expensive, energy-intensive process, but could the wonder material graphene make it more accessible?
New Discovery Could Unlock Graphene’s Full Potential

Watch the Video: