Lockheed Martin Tests Nanofilters for Oil and Gas Wastewater Management


The company states that the ultimate goal is water desalination, but more feasible and immediate uses can be found in the oil and gas industry, where the requirements in terms of the quality of the graphene and hole sizes are less challenging.

Lockheed simulated-nanoporous-graphene-filtering-salt-ionsLockheed Martin is working with two firms in the oil and gas industry to assess the feasibility of using Perforene filters to clean drilling wastewater. The aim is not the total elimination of contaminants but targeting the worst of them, making the problem more manageable. This goal only requires 50-100 nanometer sized holes, compared to 1 nanometer holes required for desalination.

The company claims that commercialization of Perforene filters could begin in the next five years, possibly with some sort of medical device that would only require small amounts. Finding a way to produce graphene with single nanometer-sized holes on a commercial scale for desalination would probably take five or more years. The company has tested it only on a small scale, but the results were promising.

Lockheed is not ready to commercialize this technology yet. They are still refining the process for making the holes in graphene, and also the production process of the graphene itself. They had expected to have a prototype filter by the end of 2013. This prototype will be a drop-in replacement for current filters used in reverse osmosis (RO) plants. They hope to commercialize this technology by 2014-2015 and are looking for partners in the filter manufacturing arena.

This is not the first time we hear of water desalination using graphene membranes. In June 2012 MIT scientists have shown (in simulations) that nanoporous graphene can filter salt from water at a rate that is 2-3 orders of magnitude faster than today’s best commercial RO desalination technology. Back in October 2010 researchers from Australia and Shanghai have developed a Capacitive Deionization (CDI) application that uses graphene-like nanoflakes as electrodes (CDI is a relatively new way to purify water). Earlier in 2010 Korean researchers have made a new type of composite material made from reduced graphene oxide and magnetite that could effectively remove arsenic from drinking water.

In 2013, Lockheed Martin developed a water desalination technology with nanometer-sized holes, with hopes of commercialization around 2014-2015.

Source: reuters

Water Wars: California’s Epic Draught Has Created A New ‘Blue Gold Rush’


1-california-drought-farms

*** Note to Readers: With the installation of this first article (from the Financial Times) we will begin a series of articles addressing not only California’s “Water Disaster”, but the impact the lack of access to Clean, Abundant, Affordable WATER is having on our world – PLANET EARTH.

More importantly, we will address how we believe Nanotechnology with its ‘cross disciplines’ across many Scientific Fields “holds the KEY” to solving the World’s Water Crisis. We believe that Nanotechnology and the need for water will also create commercial opportunities and the “Opportunity to Do Well … by Doing Good”.  –  Team GNT 1-World Water Scarcityfig1

Next Week: “Nanotechnology and Desalinization – “An Answer to World’s Thirst for Water?”

(Story from the Financial Times: By Pilita Clark)

With his military fatigues and the holstered gun at his hip, Lieutenant John Nores Jr. is a slightly unnerving sight as he slips through the woody foothills overlooking the southern edge of California’s Silicon Valley. But what the 45-year-old game warden has come to look at is more alarming.

Here in the late summer heat, not far from the sleek headquarters of technology giants Apple and Google, he leads the way to a carefully hidden patch of terraced ground pockmarked with hundreds of shallow holes that until very recently contained towering marijuana plants.

1-CA MJ aeecf23a-5943-11e4-9546-00144feab7deThere were about 2,000 plants here,” says Lt Nores as he explains how he and his colleagues from California’s fish and wildlife department recently launched an early morning raid on the plantation, ripping out a crop worth about $6m to the Mexican drug cartel that grew it”

In deep trouble

California pioneered laws allowing marijuana use for medical reasons. But it has yet to follow states such as Colorado that permit recreational use and, in any case, this crop was on public land, making it illegal and dangerous to eliminate – Lt. Nores has witnessed several shoot-outs over the past decade.

He estimates that each of the state’s 2,000-odd cartel pot farms contains an average of 5,000 plants, and that each one sucks up between eight and 11 gallons of water a day, depending on the time of year. That means at least 80m gallons of water – enough for more than 120 Olympic-size swimming pools – is probably being stolen daily in a state that in some parts is running dry as a three-year-old drought shrinks reservoirs, leaves fields fallow and dries wells to the point that some 1,300 people have had no tap water in their homes for months.

Jerry Brown, California’s governor, declared a state of emergency in January after the driest year on record in 2013, but as the annual wet season beckons, the prospect of a complete drought recovery this winter is highly unlikely, government officials say.

“Marijuana cultivation is the biggest drought-related crime we’re facing right now,” says Lt Nores as he pokes at a heap of plastic piping the growers used to divert water from a dried-up creek near the plantation.

But California’s drought is exposing a series of problems in the US’s most populous state that are a reminder of an adage popularized by Michael Kinsley, the columnist: the scandal is often not what is illegal but what is legal.

Growing competition

The theft of 80m gallons of water a day by heavily armed marijuana cartels is undoubtedly a serious concern, not least when the entire state is affected by drought and 58 per cent is categorized as being in “exceptional drought”, as defined by the government-funded US Drought Monitor.

However, this is a tiny fraction of the water used legally every day in a state that, like so many other parts of the world, has a swelling population driving rising competition for more heavily regulated supplies that have long been taken for granted and may face added risks as the climate changes.

California has always been a dry state. For almost six months of the year many of its citizens get little rain. There have been at least nine statewide droughts since 1900, not counting the latest one.

The state’s history is littered with water wars, among them the conflicts surrounding Los Angeles’s move to siphon off most of the Owens river last century that inspired the classic 1974 film, Chinatown . That dispute was over just one part of a vast system of canals and reservoirs built in the last 100-odd years that are the reason California is sometimes called the most hydro-logically altered landmass on the planet.

The system channels water from wetter to drier spots, using rivers and streams that in a normal year fill with melted snow from mountain ranges ringing the state, supplying about a third of California’s farms and cities.

1-CA short_of_water_caThe crisis is more severe because a decline in snowfall has compounded problems caused by the lack of rain. The state’s mountain snowpack was just 18 per cent of its average earlier this year, a situation scientists say could be repeated as the climate warms.

As a result eight major reservoirs were last week holding less than half their average storage for this time of year. Reservoir levels sank worryingly when a bad drought hit California in 1976-77, but there were fewer than 22m people in the state then, compared with 38.3m now.

There were also fewer laws such as those protecting creatures such as the endangered Delta smelt, a finger-sized fish that can be affected by the management of the canal system, prompting restrictions on pumping the water used by a farming sector that accounts for nearly 80 per cent of the state’s human water use. Those laws regularly inflame debate between conservationists and farmers during droughts – and are doing so again today.

The farmer’s story

“I farm in a very environmentally conscious manner, but these regulations have made it much worse for the farmers,” says Barat Bisabri, a citrus and almond farmer whose property lies in the Central Valley, one of the regions worst hit by the drought.

This flat, fertile strip runs south for about 450 miles from the northern reaches of the Sacramento Valley through the heart of the state and grows a lot of what America eats. Nearly half the fruit and nuts grown in the US come from California, including 80 per cent of the world’s almonds.

An investigation into how businesses are having to adapt to rising water costs around the world

Much of that produce comes from the Central Valley, where farming is carried out on an industrial scale. Crops and orchards grow up to the edge of people’s houses. Driving down the valley’s long, straight roads, it is striking to see an orchard of dead, brown trees next to another with puddles of water around healthy ones.

This may partly be a symptom of a century-old water rights system that critics say is so weak and archaic it makes it hard for regulators to tell whose supplies should be cut during a drought.

Mr. Bisabri’s grim predicament shows why one study estimates the drought will cost the state $2.2bn in 2014.

From the windows of the roomy farmhouse that overlooks row upon row of the property’s citrus trees, Mr Bisabri points to two of California’s main waterways, the Delta-Mendota Canal and the California Aqueduct. Both run straight through his farm but because of the drought, authorities have sharply limited the amount of water many users can take from them.

“Unfortunately we cannot get water from either of them this year,” says Mr Bisabri, as he explains how, a few weeks earlier, he used bulldozers to rip out 85 acres of healthy mandarin, orange and grapefruit trees that would have used so much water it would have made the rest of the crop far less valuable.

“I had to make a decision to kill some so the other ones could survive,” he says, as he drives to the bare patch where the trees once stood. “Had I not made that decision and kept all the citrus that we had, then I would have run out of water in the middle of August.” It is a dilemma facing farmers across the Central Valley, many of whom have shifted from crops such as tomatoes or peppers to more valuable almonds or other trees that cannot be left unwatered in a dry year.

Perennial crops such as nuts and grapes accounted for 32 per cent of the state’s irrigated crop acreage in 2010, up from 27 per cent in 1998. The shift has been even more marked in the southern Central Valley, so when drought hits, farmers face difficult choices.

A few miles down the road from his farm, Mr Bisabri stops at a jaw-dropping sight by an almond orchard of withered trees: a huge earthmoving machine is scooping up several at a time and feeding them into another machine that grinds them with an ear-splitting roar into great mounds of woodchip.

“That is exactly the same machine that we used on my farm,” he says.

Mr Bisabri has had to bring in water from other sources this year, but he says the price was almost $1.2m, 10 times what it was the previous year.

That does not include the $250,000 he spent on digging new wells to try to get supplies from the one source farmers and communities have always turned to in times of drought: groundwater.

In a normal year, aquifers supply about a third of the state’s water. In a drought, that can rise to as much as 60 per cent. But one of the most alarming aspects of this drought is that groundwater levels are plummeting.

“Water levels are dropping at an incredibly rapid rate in some places, like 100ft a year,” says Michelle Sneed, a hydrologist with the US Geological Survey who monitors groundwater in the Central Valley. “It is very extreme. Ordinarily, talking with hydrologists, if you would talk about a well dropping 10ft a year that would really get somebody’s attention, like wow! Really? Ten feet? And now we’re 10 times that.”

The depletion of this vital resource is not just a concern because it is so difficult to refill some aquifers when drought eventually subsides. It is also creating extraordinary rates of subsidence because as the groundwater disappears the land above it can sink. In one part of the valley, land has been subsiding by almost a foot a year, which Ms Sneed says is among the fastest rates anywhere in the world.

This is damaging the very canal system California built to reduce reliance on groundwater, she says, because these waterways depend on gravity for a steady flow and when parts of a canal start sinking it creates a depression that needs more water to fill it before flows can resume.

‘We ran out of water in June’

Two hours’ drive south from Mr. Bisabri’s farm, the town of East Porterville has more pressing groundwater worries. At least 1,300 people in the town rely for drinking and bathing water on wells that have gone dry as the drought has deepened.

“We ran out of water in June,” says Donna Johnson, a 72-year-old retired counsellor who delivers water to dozens of dry households from the back of her pick-up truck. Ms Johnson depends on a hose running to her home from a neighbor whose well is still working.

Until now, California has been notable among dry, western states for a pump-as-you-please approach to groundwater. A powerful agricultural lobby resisted repeated attempts at reform.

But the severity of this drought finally led to a package of measures signed into law in September requiring local agencies to monitor and manage wells, or face state intervention. Some critics say it is too little too late: many local agencies will have five to seven years to come up with plans, and until 2040 to implement them. Still, it is a lot better than nothing, say others.

“It’s a giant step for California,” says Robert Glennon, a law professor at the University of Arizona and the author of Unquenchable: America’s Water Crisis and What To Do About It . “You cannot manage what you don’t measure, full stop.”

The crisis may also encourage approval of another measure to be voted on in November allowing billions of dollars to be borrowed for new reservoirs and other steps to strengthen drought resilience.

None of this will help farmers such as Mr. Bisabri or the residents of East Porterville this year. Still, it is one more example of how the state often responds to a serious drought, says Jay Lund, a water expert at the University of California, Davis.

“Every drought brings a new innovation where we say, ‘Oh, here’s something we haven’t been doing that would really be helpful’,” says Prof Lund, pointing to irrigation systems, reservoirs and water markets rolled out after past dry spells.

“In this drought, it’s groundwater regulation so far,” he says. And will it eventually work? “It opens the door.”

That is small comfort when the latest outlook from the US Climate Prediction Center suggests the drought “will likely persist or intensify in large parts of the state” this winter.

1-World water-shortage“If there’s no water for people to live, and you don’t have the basic necessities of life, your population is going to leave,” says Andrew Lockman, the emergency services manager responsible for East Porterville. “Our primary economic driver is agriculture. If there’s no water to water crops, we’re not going to have any agriculture business, so you could see the economy of this area just decimated.”

Next Week: “Nanotechnology and Desalinization – “An Answer to World’s Thirst for Water?”

1-World Water Scarcityfig1

Genesis Nanotech Headlines Are Out!


Organ on a chip organx250Genesis Nanotech Headlines Are Out! Read All About It!

https://paper.li/GenesisNanoTech/1354215819#!headlines

Visit Our Website: www.genesisnanotech.com

Visit/ Post on Our Blog: https://genesisnanotech.wordpress.com

 

SUBCOMMITTE EXAMINES BREAKTHROUGH NANOTECHNOLOGY OPPORTUNITIES FOR AMERICA

Chairman Terry: “Nanotech is a true science race between the nations, and we should be encouraging the transition from research breakthroughs to commercial development.”

WASHINGTON, DCThe Subcommittee on Commerce, Manufacturing, and Trade, chaired by Rep. Lee Terry (R-NE), today held a hearing on:

“Nanotechnology: Understanding How Small Solutions Drive Big Innovation.”

 

 

electron-tomography

“Great Things from Small Things!” … We Couldn’t Agree More!

 

Nanoscale Desalination of Seawater Through Nanoporous Graphene


By Silvia Román

saltwaterPerhaps 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 materials science, since similar breakthroughs have ended up confined to the limits of the lab bench. Nevertheless, the outstanding properties of this one-atom thick 2D lattice of carbon atoms promise equally outstanding developments in the future.

In the meantime, new and exciting potential uses appear from time to time that keep us in suspense. One of the prospective uses currently attracting more attention is that of the nanoporous graphene materials. An interesting review recently published in Materials Today examines the last discoveries both in the production and application of this graphene-based nanocellular structure. Nanoporous graphene consists of a two-dimensional graphene sheet in which a pattern of nano-sized porous distribution has been achieved by means of different techniques, among them, electron-beam irradiation or chemical vapor deposition.

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 materials science, since similar breakthroughs have ended up confined to the limits of the lab bench. Nevertheless, the outstanding properties of this one-atom thick 2D lattice of carbon atoms promise equally outstanding developments in the future. In the meantime, new and exciting potential uses appear from time to time that keep us in suspense.

One of the prospective uses currently attracting more attention is that of the nanoporous graphene materials. An interesting review1 recently published in Materials Today examines the last discoveries both in the production and application of this graphene-based nanocellular structure. Nanoporous graphene consists of a two-dimensional graphene sheet in which a pattern of nano-sized porous distribution has been achieved by means of different techniques, among them, electron-beam irradiation or chemical vapor deposition.

 

Figure 1. Graphene has a unique one-atom thick structure made of carbon atoms arranged in a honeycomb lattice (left). Nanoporous graphene consists of creating nano-sized porous along this hexagonal graphene lattice (right). Credit: Wikimedia Commons (left); National Energy Research Scientific Computer Center (NERSC) (right)
Figure 1. Graphene has a unique one-atom thick structure made of carbon atoms arranged in a honeycomb lattice (left). Nanoporous graphene consists of creating nano-sized porous along this hexagonal graphene lattice (right). Credit: Wikimedia Commons (left); National Energy Research Scientific Computer Center (NERSC) (right)

Creating a porous structure in any kind of material always leads to new interesting properties. We have learned a lot from nature, as porous structures are constantly appearing in naturally occurring materials such as bones or wood. In the last few years materials scientists are paying much more attention to the properties arising from materials with nano-sized porosity, also known as nanofoams. In the case of graphene, this nanoporosity seems to considerably widen its range of uses. To name a few, it opens the band gap of the graphene sheets, allowing its use in field effect transistors (FETs), very limited in pristine graphene due to its zero band gap; moreover, the presence of porous in its structure increases the surface area per volume which in turn increases the content of edges acting as adsorbing sites suitable for molecular sensing applications.

 

Figure 2. Transmission electron microscopy (TEM) images of nanoporous in a graphene sheet. The scale bars correspond to 2nm (a) and 10 nm (b). | Credit: Yuan et al (2014)
Figure 2. Transmission electron microscopy (TEM) images of nanoporous in a graphene sheet. The scale bars correspond to 2nm (a) and 10 nm (b). | Credit: Yuan et al (2014)

But without any doubt, one of the most remarkable uses of nanoporous graphene might well be that of selective molecular sieving. There are several properties that make nanoporous graphene the ultimate selective membrane: its exceptional mechanical strength, its atomic thickness and the possibility to physically or chemically modify the graphene pores in order to create different barriers for different molecules. As soon as this potential use of nanoporous graphene as a filter for certain molecules was envisaged, the possibility of applying this new material to desalination of seawater became a focal point for materials scientists. It is well known that the shortage of water resources for human activities is one of the most urgent problems worldwide, while oceans and seas contain around 97% of the planet’s water.

That’s why desalination could become an ultimate solution where depletion and deterioration of water resources are already unavoidable. However, as easy as this solution could appear at first sight, desalination technologies still require high technical investments and large energy consumption. The most efficient and cost-effective technology at the moment is that of reverse osmosis (RO), but the transport of water across membranes using RO is still quite slow.

It seems that the use of nanoporous membranes as filters would considerably speed up this water flow through the nano-sized channels. Furthermore, taking into account that the flux across a membrane scales inversely with the membrane’s thickness, the one-atom thick graphene structure would become the ideal material for this purpose. Like most of the ongoing studies related to nanoporous graphene, its use for desalination of sea water has been analyzed computationally, mostly using classical molecular dynamics simulations.

That is the case of a very well known study from Professor Jeffrey C. Grossman2, from the Massachusetts Institute of Technology (MIT), in which a complete study of the nanoporous graphene behaviour has been carried out mainly considering three critical parameters: pore size, chemical functionalization of pore’s edges and applied pressure over the membrane.

Figure 3. Nanoporous graphene acts as a filter allowing water flow while rejecting salt ions. | Credit: Grossman and Cohen-Tanugi (2012)
Figure 3. Nanoporous graphene acts as a filter allowing water flow while rejecting salt ions. | Credit: Grossman and Cohen-Tanugi (2012)

Chemical functionalization of pore’s edges has been proved to have an important impact in the flux across nanoporous membranes. In this study, they altered the pore chemistry using both hydrogen groups (H-) and hydroxyl groups (OH-). The hydrogenated pores were obtained by passivating the graphene’s carbon atoms at the pore edge with hydrogen atoms, while hydroxylated pores were obtained by bonding hydrogen groups and hydroxyl groups alternatively to the unsaturated carbon atoms along the pore edge.

The result can be seen in figure 4 (a and b). Of course, pore size has to be large enough to allow water molecules flow, but narrow enough to hinder the passage of salt ions. As the pore size increases, the water permeability is higher, and then the water flow speeds up. However, larger pore areas also lead to less effective salt rejection, so that a compromise between water permeability and salt rejection must be achieved.

It seems that hydroxylated pores behave better than hydrogenated pores regarding water permeability. The authors attribute this result to an entropic effect. The hydrophobic nature of H-pores restricts the number of configurations in which water molecules can cross the membrane, while the hydrophilic nature of OH-pores allows different conformations for water molecules inside the pore, then accelerating the water flow. On the contrary, regarding salt rejection, the authors found that H-pores behave better than OH-pores. The latter are more likely to bond with salt ions and, as a result, the free energy barrier to ionic passage is reduced.

Figure 4. (a) Hydrogen groups (H-) and (b) hydroxyl groups (OH-) attached to the carbon atoms along the pore edges alter the pore chemistry and thus the water permeability of the graphene membrane. (c) Under an external applied pressure the water flows through the nano-channels while salt ions’ passage is restricted. | Credit: Grossman and Cohen-Tanugi (2012)
Figure 4. (a) Hydrogen groups (H-) and (b) hydroxyl groups (OH-) attached to the carbon atoms along the pore edges alter the pore chemistry and thus the water permeability of the graphene membrane. (c) Under an external applied pressure the water flows through the nano-channels while salt ions’ passage is restricted. | Credit: Grossman and Cohen-Tanugi (2012)

All in all, using these chemically modified nanoporous graphene membranes results in an increase of several orders of magnitude in the water permeability than that of the reverse osmosis (RO) membranes.

Nevertheless, there are also some critical aspects that will have to be properly improved: first of all, mechanical stability under applied pressure, although inherent in this material, could be improved by adding a support layer to the graphene membrane; on the other hand, a narrower pore size distribution would considerably improve the salt rejection performance of the membrane, allowing lower applied pressures and energy requirements. The authors suggest that the use of improved bottom-up methods in the production of nanoporous graphene will result in a remarkable progress of this kind of structures.

 

Figure 5. Functionalized porous graphene exhibits higher water permeability than other existing desalination methods without reducing its salt rejection performance. | Credit: Grossman and Cohen-Tanugi (2012)
Figure 5. Functionalized porous graphene exhibits higher water permeability than other existing desalination methods without reducing its salt rejection performance. | Credit: Grossman and Cohen-Tanugi (2012)

While everybody is waiting for the graphene revolution to translate into real-world applications, the experts claim that graphene market should start to take off after 2015, and it will take some years for all these new technologies to live up to its full potential. Graphene will have to attract technological markets enough for them to make large investments in its mass production and finally allow these high expectations turn into large-scale industrial applications.

References

  1. Yuan W. & Gaoquan Shi (2014). Nanoporous graphene materials, Materials Today, 17 (2) 77-85. DOI: http://dx.doi.org/10.1016/j.mattod.2014.01.021
  2. Cohen-Tanugi D., Grossman J. C., (2012) Water Desalination across Nanoporous Graphene, Nano Letters, 12, p. 3602-3608. dx.doi.org/10.1021/nl3012853