Rice University: NEWT: New One-Step Catalyst Converts Nitrates to Water and Air


Rice Water Air Nitrates 159751_webRice University’s indium-palladium nanoparticle catalysts clean nitrates from drinking water by converting the toxic molecules into air and water. Credit Jeff Fitlow/Rice University

A simple, one-step catalyst could help yield cleaner drinking water with less nitrates.

A team from Rice University’s Nanotechnology Enabled Water Treatment (NEWT) Center have discovered that a catalyst made from indium and palladium can clean toxic nitrates from drinking water by converting them into air and water.

“Indium likes to be oxidized,” co-author Kim Heck, a research scientist at Rice, said in a statement. “From our in situ studies, we found that exposing the catalysts to solutions containing nitrate caused the indium to become oxidized.

“But when we added hydrogen-saturated water, the palladium prompted some of that oxygen to bond with the hydrogen and form water, and that resulted in the indium remaining in a reduced state where it’s free to break apart more nitrates,” she added.

In previous research, the researchers discovered that gold-palladium nanoparticles were not good catalysts for breaking apart nitrates. This led to the discovery of indium and palladium as a suitable catalyst.

“Nitrates are molecules that have one nitrogen atom and three oxygen atoms,” Rice chemical engineer Michael Wong, the lead scientist on the study, said in a statement. “Nitrates turn into nitrites if they lose an oxygen, but nitrites are even more toxic than nitrates, so you don’t want to stop with nitrites. Moreover, nitrates are the more prevalent problem.

“Ultimately, the best way to remove nitrates is a catalytic process that breaks them completely apart into nitrogen and oxygen or in our case, nitrogen and water because we add a little hydrogen,” he added. “More than 75 percent of Earth’s atmosphere is gaseous nitrogen, so we’re really turning nitrates into air and water.”

Nitrates, which could also be a carcinogenic, are considered toxic to both infants and pregnant women.

Nitrate pollution is common in agricultural communities, especially in the U.S. Corn Belt and California’s Central Valley, where fertilizers are heavily used. Studies have shown that nitrate pollution is on the rise because of changing land-use patterns. 1-california-drought-farms

The Environmental Protection Agency regulates allowable limits both nitrates and nitrites for safe drinking water. In communities with polluted wells and lakes, that typically means pretreating drinking water with ion-exchange resins that trap and remove nitrates and nitrites without destroying them.

“Nitrates come mainly from agricultural runoff, which affects farming communities all over the world,” Wong said. “Nitrates are both an environmental problem and health problem because they’re toxic.

“There are ion-exchange filters that can remove them from water, but these need to be flushed every few months to reuse them, and when that happens, the flushed water just returns a concentrated dose of nitrates right back into the water supply.”

The researchers will now try to develop a commercially viable water-treatment system.

“That’s where NEWT comes in,” Wong said. “NEWT is all about taking basic science discoveries and getting them deployed in real-world conditions.

“This is going to be an example within NEWT where we have the chemistry figured out, and the next step is to create a flow system to show proof of concept that the technology can be used in the field,” he added.

The study was published in ACS Catalysis.

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Rice University (NEWT) / China team use phage-enhanced nanoparticles to kill bacteria that foul water treatment systems


Clusters of nanoparticles with phage viruses attached find and kill Escherichia coli bacteria in a lab test at Rice University. 

Abstract:
Magnetic nanoparticle clusters have the power to punch through biofilms to reach bacteria that can foul water treatment systems, according to scientists at Rice University and the University of Science and Technology of China.
Magnetized viruses attack harmful bacteria: Rice, China team uses phage-enhanced nanoparticles to kill bacteria that foul water treatment systems.

Researchers at Rice and the University of Science and Technology of China have developed a combination of antibacterial phages and magnetic nanoparticle clusters that infect and destroy bacteria that are usually protected by biofilms in water treatment systems. (Credit: Alvarez Group/Rice University)

The nanoclusters developed through Rice’s Nanotechnology-Enabled Water Treatment (NEWT) Engineering Research Center carry bacteriophages – viruses that infect and propagate in bacteria – and deliver them to targets that generally resist chemical disinfection.

Without the pull of a magnetic host, these “phages” disperse in solution, largely fail to penetrate biofilms and allow bacteria to grow in solution and even corrode metal, a costly problem for water distribution systems.

The Rice lab of environmental engineer Pedro Alvarez and colleagues in China developed and tested clusters that immobilize the phages. A weak magnetic field draws them into biofilms to their targets.

The research is detailed in the Royal Society of Chemistry’s Environmental Science: Nano.
“This novel approach, which arises from the convergence of nanotechnology and virology, has a great potential to treat difficult-to-eradicate biofilms in an effective manner that does not generate harmful disinfection byproducts,” Alvarez said.

Biofilms can be beneficial in some wastewater treatment or industrial fermentation reactors owing to their enhanced reaction rates and resistance to exogenous stresses, said Rice graduate student and co-lead author Pingfeng Yu. “However, biofilms can be very harmful in water distribution and storage systems since they can shelter pathogenic microorganisms that pose significant public health concerns and may also contribute to corrosion and associated economic losses,” he said.

The lab used phages that are polyvalent – able to attack more than one type of bacteria – to target lab-grown films that contained strains of Escherichia coli associated with infectious diseases and Pseudomonas aeruginosa, which is prone to antibiotic resistance.

The phages were combined with nanoclusters of carbon, sulfur and iron oxide that were further modified with amino groups. The amino coating prompted the phages to bond with the clusters head-first, which left their infectious tails exposed and able to infect bacteria.

The researchers used a relatively weak magnetic field to push the nanoclusters into the film and disrupt it. Images showed they effectively killed E. coli and P. aeruginosa over around 90 percent of the film in a test 96-well plate versus less than 40 percent in a plate with phages alone.

The researchers noted bacteria may still develop resistance to phages, but the ability to quickly disrupt biofilms would make that more difficult. Alvarez said the lab is working on phage “cocktails” that would combine multiple types of phages and/or antibiotics with the particles to inhibit resistance.

Graduate student Ling-Li Li of the University of Science and Technology of China, Hefei, is co-lead author of the paper. Co-authors are graduate student Sheng-Song Yu and Han-Qing Yu, a professor at the University of Science and Technology of China, and graduate student Xifan Wang and temporary research scientist Jacques Mathieu of Rice.


The National Science Foundation and its Rice-based NEWT Engineering Research Center supported the research.

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

Technology could make treatment and reuse of oil and gas wastewater simpler, cheaper – University of Colorado + MIT + Rice Universities (NEWT)


fracking-happeningOil and gas operations in the United States produce about 21 billion barrels of wastewater per year. The saltiness of the water and the organic contaminants it contains have traditionally made treatment difficult and expensive.

Engineers at the University of Colorado Boulder have invented a simpler process that can simultaneously remove both salts and  from the wastewater, all while producing additional energy. The new technique, which relies on a microbe-powered battery, was recently published in the journal Environmental Science Water Research & Technology as the cover story.

“The beauty of the technology is that it tackles two different problems in one single system,” said Zhiyong Jason Ren, a CU-Boulder associate professor of environmental and sustainability engineering and senior author of the paper. “The problems become mutually beneficial in our system—they complement each other—and the process produces energy rather than just consumes it.”

The new treatment technology, called microbial capacitive desalination, is like a battery in its basic form, said Casey Forrestal, a CU-Boulder postdoctoral researcher who is the lead author of the paper and working to commercialize the technology. “Instead of the traditional battery, which uses chemicals to generate the electrical current, we use microbes to generate an electrical current that can then be used for desalination.” cu-desal-cell-microbio-c2ee21737f-f1

This microbial electro-chemical approach takes advantage of the fact that the contaminants found in the wastewater contain energy-rich hydrocarbons, the same compounds that make up and . The microbes used in the treatment process eat the hydrocarbons and release their embedded energy. The energy is then used to create a positively charged electrode on one side of the cell and a negatively charged electrode on the other, essentially setting up a battery.

Because salt dissolves into positively and negatively charged ions in water, the cell is then able to remove the salt in the wastewater by attracting the charged ions onto the high-surface-area electrodes, where they adhere.

Not only does the system allow the salt to be removed from the wastewater, but it also creates additional energy that could be used on site to run equipment, the researchers said.

“Right now have to spend energy to treat the wastewater,” Ren said. “We are able to treat it without energy consumption; rather we extract energy out of it.”

Some oil and gas wastewater is currently being treated and reused in the field, but that treatment process typically requires multiple steps—sometimes up to a dozen—and an input of that may come from diesel generators.

Because of the difficulty and expense, wastewater is often disposed of by injecting it deep underground. The need to dispose of wastewater has increased in recent years as the practice of hydraulic fracturing, or “fracking,” has boomed. Fracking refers to the process of injecting a slurry of water, sand and chemicals into wells to increase the amount of oil and natural gas produced by the well.

Injection wells that handle wastewater from fracking operations can cause earthquakes in the region, according to past research by CU-Boulder scientists and others.cu-boulder-maxresdefault

The demand for water for fracking operations also has caused concern among people worried about scarce water resources, especially in arid regions of the country. Finding water to buy for fracking operations in the West, for example, has become increasingly challenging and expensive for oil and gas companies.

Ren and Forrestal’s microbial capacitive desalination cell offers the possibility that water could be more economically treated on site and reused for fracking.

To try to turn the technology into a commercial reality, Ren and Forrestal have co-founded a startup company called BioElectric Inc. In order to determine if the technology offers a viable solution for oil and gas companies, the pair first has to show they can scale up the work they’ve been doing in the lab to a size that would be useful in the field.

The cost to scale up the technology also needs to be competitive with what oil and gas companies are paying now to buy water to use for fracking, Forrestal said. There also is some movement in state legislatures to require oil and gas companies to reuse wastewater, which could make BioElectric’s product more appealing even at a higher price, the researchers said.

mit-gradiantcorp-071715-2MIT – Toward Cheaper Water Treatment for Oil & Gas Operations

MIT spinout makes treating, recycling highly contaminated oilfield water more economical

0629_NEWT-log-lg-310x310Also Read: Nanotechnology Enabled Water Treatment or NEWT: Transforming the Economics of Water Treatment: Rice, ASU, Yale, UTEP win $18.5 Million NSF Engineering Research Center

 

 

 

Explore further: New contaminants found in oil and gas wastewater

More information: “Microbial capacitive desalination for integrated organic matter and salt removal and energy production from unconventional natural gas produced water.” Environ. Sci.: Water Res. Technol., 2015,1, 47-55 DOI: 10.1039/C4EW00050A

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YouTube Video: Genesis Nanotechnology Nano Enabled Water Treatment; Quantum Dots from Coal & More

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


img_0750
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

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

 

Read More on How New (Nano) Technology Can Help Solve Our Looming Water Issues

MIT Solar Water Power splashMIT: How can we Use Renewable Energy to Solve the Water Crisis – Solar Desalination? (Video)

Published 2015 Water scarcity is a growing problem across the world. John H. Lienhard V and his team at MIT are exploring how to make renewable energy more efficient and affordable. Mechanical engineers and nanotechnologists are looking at different methods, including solar desalination. COMING ~ JUNE 2015 ~ “Great Things from Small Things” ~ Watch […]

Graphene Nano Membrane 071615How Graphene Desalination Could Solve Our Planet’s Water Supply Problems: Video

World WAter Short Map 033016 uci_news_image_downloadNanoscale Desalination of Seawater Through Nanoporous Graphene

Perhaps the most repeated words in the last few years when talking about graphene — since scientists Geim and Novoselov were awarded the Nobel Prize in Physics in 2010 for their groundbreaking experiments — are “the material of the future”. There are some risks regarding so many expectations about everything related to […]

Silver Nano P clean-drinking-water-indiaNanotechnology to provide efficient, inexpensive water desalination

How Nanotechnology is Poised to Change Medicine Forever


Medicine Nano 052616 hqdefault

*** Re-Posted from “Big Think”

Science fiction movies such as Ant-Man and Fantastic Voyage excite us about the possibility of shrinking ourselves down to the subatomic level. In the Disney version of The Sword in the Stone, Merlin defeats the sorceress Madam Mim in a shape shifting battle by turning into a microbe which makes her sick. All of these touch upon the power that comes with being able to control what is infinitesimally small. In reality, science has made great progress in this regard. But we’re not quite there yet. The prefix nano comes from ancient Greek meaning, “dwarf.” Mathematically speaking, it refers to one billionth of a unit of measure. For instance, a nanometer (nm) equals one billionth of a meter (0.000000001 meters). This is 40,000 times smaller than the width of a human hair, or around three to five atoms wide.

Nanotechnology is the ability to control and manipulate matter on the atomic or molecular level. This new branch of technology is already being used, albeit passively, in sunscreens and cosmetics. But future applications promise so much more. Nanotech could have a revolutionary impact on diagnostics, research, development, drug delivery, tissue repair, detox, surgery, health monitoring, and gene therapy, among other places. Consider a lab working on the subatomic level, able to create microscopic robots and tools to deliver medicines, manipulate the components of a cell, and piece together or take apart DNA. All of this may someday be commonplace in hospitals, labs, and medical centers. Right now, this technology is in its seminal stages, slowly transitioning from the realm of science fiction to science fact.

Possible uses of nanotech.

Nanotech could theoretically stretch DNA out like a bundle of wires. The nanobots would carry out repairs, or snip out faulty genes and replace them with healthy ones. This might someday make hereditary conditions obsolete. In 2004, New York University (NYU) chemists were able to create a nanobot from fragments of DNA able to walk on two legs, each a mere 10 nanometers long. This “nanowalker” could take two steps forward or back. Ned Seeman was one of the researchers on this project. He believes someday that a molecular scale assembly line could be fashioned. A molecule could be moved along and put into place by nanobots in order to engage certain health effects.

Nanobots are also being used to fight cancer. Harvard Medical School scientists recently reported an “origami nanorobot” comprised of DNA. Researchers successfully displayed how these could be used to deliver deadly molecules to lymphoma and leukemia cells, causing them to commit suicide. At Northwestern University nanostars have been developed. These are star shaped nanobots able to deliver drugs directly to cancer cells. Researchers showed that they could dispatch such drugs directly to the nuclei of ovarian and cervical cancer cells. The body often breaks down such drugs before they can be delivered. Nanostars may someday overcome this problem.

Different shapes of nanotech currently proposed.

Now consider “nanofactories.” Researchers at MIT showed how self-assembling proteins could deliver drugs directly to problem areas. So far, tests have been successful in laboratory mice, where nanoparticles released a specific protein when exposed to UV light. This may prove useful in fighting metastatic tumors, or those who send cancer cells to invade other organs and tissues, causing the cancer to spread. Metastatic disease is responsible for over 90% of all cancer deaths.

Nanofibers are another innovation coming down the pike. These are 1,000 nanometers or less in diameter. They might serve as components to artificial organs or tissues, surgical textiles, and even the next generation of wound dressings. Another area of promise is medical imaging. Nanoparticles could be used to achieve more precise imaging, aiding diagnostics and guiding surgeons. Matthew MacEwan, of the Washington University School of Medicine in St. Louis, has launched his own nanofiber company. These fibers can be used to repair bone, soft tissue, nerves, and even spinal cord and brain tissue in the wake of a debilitating injury.

Japanese researcher holding nanofiber sheet.

Though these possible innovations in nanotech sound wondrous, there are still many challenges ahead. Being a cutting-edge technology, the cost is high, limiting research and the ability to scale up production. This causes timetables to be stretched much farther out. A segment of the public is also wary of nanobots swimming around in their systems. Some are worried that the small size may cause complications, though there is no indication thus far that this technology is at all dangerous.

In fact, most researchers in the field say these particles are less toxic than your average household cleaning product. Nanoparticles are simply a part of nature. Theoretically however, if they do end up in the wrong part of the body or malfunction, they might cause disease instead of alleviating it. Then there are more ghastly fears. Could nanotech create robots which enter our brains and cause us to comply with government wishes, a new kind of 1984? Might it lead to an undetectable weapon able to propagate a new kind of terrorism? For now, these fears remain in the realm of science fiction. Whether or not future innovations allow these possibilities to surface is still up for debate. Today, the cost is too great for such worries to materialize, even on the molecular level.

Learn more here:

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Is Capacitive Deionization The Key To Desalination?


Deionization 042916 375_250-saltCapacitive deionization (CDI) is a process by which the ions are removed from water with the use of two electrodes. A positively charged electrode captures the water’s negatively charged anions while a negatively charged electrode captures the water’s positively charged cations.

“The technology can be best thought of as a tool which removes dissolved ionic species from a solvent using highly porous carbon electrodes charged to a small voltage,” explained Matthew Suss, assistant professor at the Israel Institute of Technology. “It works by a phenomenon known as electrosorption, where charging the porous carbon electrodes positively allows for dissolved ions of opposite charge to be brought to the pore surface and held there electrostatically. In this way, ions are removed from the water and held along the surface until the voltage is removed.”

This may seem like an abstract practice until you remember that salt is an ionic compound and that through CDI, it can be removed from water.

In the 2015 study “Water desalination via capacitive deionization: what it is and what you can expect” published by the Royal Society of Chemistry, Suss and a team of researchers take a long view at a field that has grown rapidly in the last few years, in large part because of its implications for the water industry.

“It is a highly scalable technique which does not require much energy for brackish water desalination,” he said. “To run it, you need mainly a low-voltage input, so no high-pressure pumps or heat sources are required.”

Probably the most popular desalination alternative to CDI is reverse osmosis (RO). That involves using high-pressure pumps to force water through semipermeable membranes which screen out the salt. These pumps need lots of energy to keep running and the process requires about 5 kWh to produce a cubic meter of freshwater, according to an online encyclopedia of desalination and water resources.

In contrast, a Chinese CDI operation featured in Suss’ study reported energy consumption around 1 kWh for every cubic meter of freshwater produced.

In their study, Suss and his research team put the water recovery ratio (the ratio of produced freshwater volume to feedwater volume) for a typical seawater reverse osmosis (SWRO) plant at 45 percent to 55 percent, while CDI systems have the potential to attain a ratio significantly higher than 55 percent.

However, as a relatively new technology there aren’t that many full-scale operations that utilize CDI. It’s hard to gauge how well it could perform if widely employed.

“It is a fast-emerging technology in the research world and so that is now translating to growth in the industry,” as Suss put it. “The main obstacle is the lack of demonstration plants and scaled-up systems at the moment. Most systems are lab-scale right now.”

With water scarcity propelling us to find creative solutions just so we have enough to drink, it won’t be long until CDI gets its time in the spotlight.

Image credit: “Salt,” © 2008 Kevin Dooley, used under an Attribution­ShareAlike 2.0 Generic license: http://creativecommons.org/licenses/by­sa/2.0/