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Nanorust Used To Purify Water
eldavojohn writes "How do you remove arsenic from water? Well, a research team has discovered that adding and removing nanorust works well. From the article, 'The team added nanoscale iron oxide to contaminated water, where it clumped together with the arsenic. They then magnetized the nanoparticles with an electromagnet and pulled them out. "We only needed a surprisingly weak magnetic field," says Colvin. "In fact, we could pull then out with just a hand-held magnet, making this a very practical method.' Big news for developing nations that are plagued with non-potable drinking water."
This method sounds like it could eventually have some potential, but it's not like you'll be able to take water directly from the Ganges, add some nanorust, and have fresh sparkling drinking water. In developing nations, the key is ensuring factories and agriculture do not dump their waste into the drinking supply (one of the big problems in India), that the sewage and drinking systems are separated, and that modern filtration units are used. Implementing all of these would be far cheaper than having people boil their water, and would ensure that bacteria, lead, and other impurities are removed.
... so why spend tons of money making nanorust if something else already exists that is cheaper and just as effective?
The article itself admits that nanorust is still too expensive to be used widely, while filtration units already exist that cheaply remove arsenic plus many other things cheaply. In the U.S., home filters (and even cheap Britas) remove 99% of all arsenic, along with similar levels of other chemicals and heavy metals
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"Big news for developing nations that are plagued with non-potable drinking water"
I'll pass this on to E. Coli.
but you might get even more results with picorust.
question one should be How Did the Arsenic Get In There?
Is this a normal geological property or result of pollution?
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So what's wrong with calling it something like "microscopically fine rust powder", or something else that doesn't reek of marketing buzzwords?
This is a very basic property of reaction chemistry - the greater your surface area, the quicker your reaction will proceed and the more material will actually react. This sounds like simply taking that idea to the logical limit. The real trick will be producing particles of that size cheaply and in quantity.
And where does a developing country get nanoscale iron oxide ?
And is iron oxide actually magnetic ?
Wouldn't it be more practical and cheaper ?
Removing arsenic from water does NOT require "nano" rust. Plain ordinary sand-grain-sized rust flakes will do just fine. Humans have used this "tech" for at least hundreds, if not thousands, of years, to purify water.
As the two biggest problems, though - Too much iron causes problems in humans (males in particular, and yes, for the obvious reason); and the non-water product of this technique consists of a rather toxic arsenic sludge which you occasionally need to dispose of somewhere that won't run right back into your water source.
Of course it is. But that story was covered last weak.
I know of 5 or 6 towns in my own COUNTY that need this.
I don't mean to be a dick, but the first sentence there ("Most arsenic enters water supplies either from natural deposits in the earth or from industrial and agricultural pollution") can be summarized as "some is natural and some is from pollution", which gets us nowhere until some *ratio between the two is asserted...
My turnips listen for the soft cry of your love
Arsenic occurs naturally in volcanic rocks in Hawaii. However arsenic compound was used by white man as a herbicide on sugar plantations. Now Hawaii has a 10x more arsenic than naturally occurring in rocks. In fact some of the new hosing developments have to remove topsoil to be within (Hawaii relaxed) EPA standards.
Arsenic is insoluble so it just stays in ground or gets washed away. That's why coral-reef fish and algae's are usually contaminated the most.
This is not new technology at all. Some professors i know opened a company using the lined carbon nanotubes to do the same thing around 5 years ago.
I think the really interesting part of this research is not what they say they are doing with it now--it's what could potentially come of this. I don't know what it might be useful for, but knowing that can we now do this might help us in some other area at some other point in time.
Lets see. 1 kg of rust with density ~6000 kg/m^3 = 1.67e-4 m^3.
American Football field area: 110 m * 49 m = 5390 m^2.
Thinkness of a 1-kg sheet spread over 1/6 the area of the field: 1.67e-4 m^3 / (5390/6) m^2 = 1.85e-7 m
So the surface area of 1 kg of little cubes with 1.85e-7 m sides gives one football field. 1.85e-7 is much closer to micro (1e-6) than nano (1e-9).
While I agree with the principle of what you're stating, it's not like arsenic is being created in mesurable quantities. An element is an element and stays the same one as long as no nuclear reactions are involved. So unless it's being introduced into water supplies where before it was buried safely somewhere, it's just a natural contaminant.
Where are you going to get all the nano-cars needed to generate this rust?
When our name is on the back of your car, we're behind you all the way!
The techniques for making activated charcoal are known (and cheap as long as you have some decent wood handy), as is simple plumbing using plastic buckets and spigots.
..well, stupid..normal consumer gee gaws. Say an iPod, there ya go, you can get a decent quality emergency water filtration system for the cost of the cheapest iPod, I know that for a fact. Yet..how many have them? I guess much less than 1% of the US people, much less really.
In other words, filters don't have to be expensive, just commercial units are made in too small of quantities to get the costs down to the affordable level for the poorest. It *could*be done though, if there was a will and the money spent. If you want an example for India, they could drop some of their military budget, I have no idea how many cheap filters could be made for the cost of one redundant fighter jet, but it would be considerable, if the money was spent wisely and the filters were issued as kits with a way to replace the charcoal easily. A three bucket stack with the middle bucket having charcoal, and some fine screens, and a few cheap connectors would suffice.
With that said, too few people in western "rich" nations have their own adequate filters, every natural disaster we see the results there where people might be surrounded by water, most of it unfit to drink, yet have to go stand in refugee line waiting for the government to save them, because they have no stash of water, food, basic medicaql gear, reliable backup power supplies-nothing.
Good water-filtration gravity units run 1-3 hundred dollars full retail, and I bet most of those waterless victims you see on TV have spent that on any number of
A lot of people are quick to dis the third world for lack of this or that, when they can't even be bothered themselves despite being "rich" enough to have some basic protection for critical life necessities. Thousands for luxuries, pennies or zero for necessities for most people.
Your version of your trycorder is just too big, telephones are smaller than ever, they already got small and micro dominated too. You better hail to your overlords defining what nano really is, else you won't get a nanostep further in this Star Trek universe where the primary directive might be a solution ....
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Of course it is, but in small doses it was used in the past as a stimulant. It was also used topically (way before Retin A) to clear up one's skin and to gain that dead white skin look that fashion sometimes decrees--usually, however, while still living.
Not only that - you can make it out of Volkswagens!
Personally, I always add an iodine tablet to my drinking water. Be it purified, distilled, distilled/deionized, treated with chlorine, you name it, I always add it. I grew use to the taste of iodine, and I associate the taste with safe water... Now I admit that this system seems great, and highly cool, but without that taste myself, and a lot of others, really will not trust the water....
Oh, if anyone knows if I am slowly killing myself by doing this, please tell me....
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im sure you are just baiting folks but what happens if that "pure water source is a 4 day walk in 100+ heat?
answer you will be a rotting corpse a daya away from the water
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You can easily boil water with a few steel mirrors. Distillation removes not only organic but inorganic pollutants, and renders the water sterile.
The only thing that distillation cannot deal with is the few volatile organic molecules that have a boiling point near that of water, and a charcoal filtration step on the condensate will deal with those.
Where electricity is available, a gallon of distilled water can be prepared with two kilowatt hours of energy, at a cost in most places of under sixty cents.
You can even get stovetop distillers.
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http://polymetallix.com/
They have far more details than the article.
The US government have made it clear that we have no inalienable rights; any we do not defend vigorously will be taken.
I think we used similar method around the end of the 80s, when we really couldn't trust the water authorities. I'm really not sure how it worked, but the method consisted of inserting two metal rods in the 5-liter canister, which then rusted and attracted rust particles between each other. The particles that didn't make it to the other rod fell onto the bottom. After about 2 days, the rods were pulled out, and the water was ready to drink, except for perhaps the last liter, which had a bit reddish color from rust.
I recall this mechanism was used by many, since the water quality was questionable, and no one wanted to get sick.
there is no issue with my network
Is there any knowledge out there about obtaining desalinated water using some sort of nanotech filter, other than the high-pressure blasting method used today?
Revive the Constitution.
"Rust" has been in use as a catalyser in chemical reactions for ages. One of the better known ones is probably the synthesis of ammonia on an industrial scale aka "Haber-Bosch-synthesis", developed in the early 20th century. And this new application has promise.
But god, do I ever hate the word "potable". It sounds like a hayseed trying to say "portable": "Them big ol' buckets uh water'r too heavy t'be po'table!"
The word has one and only one meaning: "drinkable". It has no distinction from this definition, either, unlike most other synonyms in the English language which at least have some nuance of meaning distinct from other words. So, would someone tell me why anyone would insist on using the word "potable" instead of "drinkable", particularly in such cases as this where both words are used?
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Right, Because poeple who live 4 days away from water have loads of nanorust....
God Be Gone
Water from the Hudson may be drinkable, but it is not potable. Water from the Chicago River is neither. Honestly, when they dump the food coloring into the Chicago River on St. Patrick's Day and it goes radioactive green for miles around it looks more appetizing than it does at any other point in the year -- the color and consistency of lime jello!
Help poke pirates in the eyepatch, arr.
" Excess iodine has symptoms similar to those of iodine deficiency. Commonly encountered symptoms are abnormal growth of the thyroid gland and disorders in functioning and growth of the organism as a whole. Elemental iodine, I2, is deadly poison if taken in larger amounts; if 2-3 grams of it is consumed, it is fatal to humans. Iodides are similar in toxicity to bromides."
Toxicity of IodineI always assumed the iodine they add to salts were good enough to cover the population base (US) from iodine deficiency.
Aren't nanoparticles of iron oxide simply jewler's rouge, the same stuff used for brightening gold and silver and in the final polish stages of harder materials?