Nanofilters could stall looming water crisis
2011 06 02

By Nicola Frost | CosmosMagazine.com


Carbon nanotubes may revolutionise the process of converting salt water to fresh water and provide an energy-saving solution to the increasing global demand for fresh drinking water, researchers say.

In a new report, computer modelling was used to study how fluid flows at the molecular level. One of their aims was to find the optimum design for a carbon nanotube (CNT) membrane that can be used in the desalination process.

Thee simulations suggest that this membrane may be 20 to 5,000 times more permeable to water than current commercial scale reverse osmosis membranes, depending on tube density.

“If a new material is found that can maximise water transport through the separating membrane, while at the same time rejecting dissolved ions and other particulates in seawater, reverse osmosis would be a much more efficient process,” said lead author Jason Reese, professor of thermodynamics and fluid mechanics at the University of Strathclyde, Glasgow, Scotland.

Demand for drinking water on the increase

With the global population predicted to reach 9.5 billion by the latter half of this century, the demand for drinking water is only going to increase. Already, more than a billion people are faced with insufficient fresh water resources.

This week, 20 former heads of state, including former U.S. president Bill Clinton and former Japanese prime minister Yasuo Fukuda, warned of an impending "water crisis", and will establish a panel to tackle a worldwide leadership gap on the issue.

Trends in climate change have been shown to predict a redistribution of rainfall globally, with dry regions of the planet only getting dryer.

Huge costs of desalination

Most desalination plants convert salt water to fresh water using reverse osmosis. Pressure is applied to the salt water solution forcing the water through a permeable membrane that separates the pure water from the salts.

There are huge costs associated with desalination plants, however, as they require expensive infrastructure and large amounts of energy. With current technology, it is five times more expensive to desalinate water than to extract groundwater, but CNTs may change this.

Carbon nanotubes are sheets of graphene – one-atom thick carbon – rolled into cylinders. Their versatility lies in the fact that they can be a nanometre in diameter, with a tube length many millions of times longer. They are highly efficient at repelling salt ions. In solution, salts are surrounded by hydrating water molecules, which must be shed in order to pass through the CNTs.

This process takes a lot of energy and as a result doesn’t happen very often. Therefore, the right sized nanotube will optimise water transport while minimising salt ion permeability.


Read the full article at: cosmosmagazine.com



Video from: YouTube.com


Video from: YouTube.com




Related Articles
NASA’s nanotube paint: Blacker than Black (Video)
Researchers create self-assembling nanodevices that move and change shape on demand
Britain: Nanoscale Energy Storage Material Under Development
Peers Criticise Food Industry Secrecy on Nanotechnology
Nuclear-Powered Nanobots Will Allow Us to Forgo Eating a Square Meal for a Century
Nanotubes Weigh A Single Atom
Study Says Carbon Nanotubes as Dangerous as Asbestos [2008]


Latest News from our Front Page

Roswell, UFOs and Project Pandora
2014 07 23
Well, now, this is interesting. In fact, it’s very interesting. Over at the Department of Defense’s website you can find a file that has been declassified via the Freedom of Information Act on the subject of Project Pandora (which, to a significant degree, was focused on Cold War secrets, and how microwaves can affect the mind and body). It’s a fascinating ...
Men of Europe, Put Down the Eckhart Tolle Book and Pick up Your Sword
2014 07 23
Remember who you really are... The New Age Tactical Spiritual Military Industrial Complex supports murder and genocide. What is happening in Gaza today will eventually take place in London, Dublin, New York, Lisbon, Barcelona, Oslo, Glasgow, Melbourne, Stockholm, Auckland and Cape Town and wherever you are reading this article. Notice is being served upon all humanity. Not just the people of ...
Study Challenges Hypothesis that Birds Evolved from Dinosaurs
2014 07 23
The re-examination of Scansoriopteryx – a sparrow-sized, pre-Archaeopteryx, bird-like creature that lived in what is today China during the Jurassic period, about 154 million years ago – challenges the widely accepted hypothesis that birds are derived from land-dwelling dinosaurs that gained the ability to fly. Unearthed in Inner Mongolia in 2002, Scansoriopteryx was previously classified as a theropod dinosaur, from which ...
Israeli Professor: Rape Hamas Militants’ Mothers and Sisters to Deter Terrorist Attacks
2014 07 23
An Israeli academic has claimed that raping wives and mothers of Palestinian Hamas militants is the only thing that could deter further terrorist attacks. The remarks by renowned Middle East scholar Mordechai Kedar of Bar-Ilan University were made three weeks ago after the grim discovery of the bodies of the three kidnapped Israeli teenagers, but the recording was published online (in ...
’Mysterious plane’ with no callsign spotted circling London for two hours
2014 07 23
Scotland Yard has declined to comment on reports of a mysterious eavesdropping spyplane circling London. A radar tracking website showed an aircraft orbiting London at 10,000 feet for more than two hours. The plane had no recognisable callsign but was identified as a twin-engine Cessna F406 with the registration G-BVJT. The aircraft has been linked in the past to a shadowy fleet of ...
More News »