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Cleaning the Environment with Iron Nanoparticles
Roland Piquepaille writes "In "Nanoscale Iron Could Help Cleanse the Environment," the National Science Foundation (NSF) reports that "nanoscale" powder made from iron could be used to clean contaminated soil and water. "Iron's cleansing power stems from the simple fact that it rusts. When metallic iron oxidizes in the presence of contaminants, these organic molecules get caught up in the reactions and broken down into simple carbon compounds that are far less toxic." Using this technology, cleaning landfills or industrial sites would cost about $5 per square meter. More details are available in this summary, including other links and a diagram showing how the method works."
Nanoscale titania (esp. anatase) is also useful for pollution cleanup. Some researchers are even combining it with nanoscale iron oxed.
See this Google search and this page
Logic is not Divine.
the size is part of the issue (smaller particles have more surface area). the more important point is that iron in the evironment is already in an oxidized state, e.g., Fe(OH)2. And it is the oxidation/reduction reaction that is driving the detoxification of the compounds. Specifically, Fe0 goes to Fe2+ or Fe3+, giving up 2 electrons which then are used to reduce the compound. (reduction also has the benefit that it usually makes the compound more amenable for microorganisms to chew up naturally).
This site has some diagrams of chemical pathways. Also try googling "zero valent iron".
That article is talking about children overdosing on iron pills. You'd have to eat a lot of dirt to get that kind of iron into your system from the ground.
...and what if it gets into the water and a lake full of fish ingest all that iron? I think the point is valid and the original post should NOT be modded Troll. That is too harsh. The link that is provided does go into detail about how iron can be poisonous.
"What happens in an iron overdose?
When someone takes too much iron, the first effect is irritation and ulceration of the stomach lining. This results in nausea, abdominal pain and vomiting as early as 20 minutes after the ingestion. This can be followed by an apparent recovery, which is very deceptive because a few hours later the person can go into pro-found shock with a severe blood chemistry imbalance. When too much iron gets into the bloodstream, it goes to all the organs and can damage the stomach, liver, kidneys, lungs, blood vessels and brain. "
The completely valid question is could this happen to animals if a lot of nanoscale particles of iron were released into the ecosystem?
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If you spray water into a fine mist in sub-zero climate, then you will get instant snow. But if you spray an ultra fine powder of iron in a humid inviroment, chances are great that it will be rust by the time it lands on the ground. In fact, all you have to do is look at your own blood. It turns red the moment the hemogobin reacts with oxygen...which is made up if trace amounts of iron.
Life is not for the lazy.
Rusting iron consumes free oxygen. When used in water sources, this can be a very Bad Thing for most closed-system watersheds.
Powdered iron has been suggested as a means of controlling greenhouse buildup by scattering hundreds of tons of it across the surface of the pacific ocean; it creates dramatic blooms of algae in the water that suck up carbon dioxide and other pollutants.
The problem to this, of course, is that the ocean is a closed-system as well, albeit a far larger one. The iron rusts, consumes oxygen, leaving fish in oxygen-deprived waters and with little place else to go. (Fish aren't immune to pressure, quite the opposite, so no, going down isn't much of an option.)
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