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Smog Busting Paint Breaks Down Noxious Gasses
jlechem writes "New Scientist is reporting a story about a new paint that can absorb noxious gas. According to the article the new paint is called Ecopaint. The substance is designed to reduce levels of the nitrogen oxides, collectively known as the NOx gases, which cause respiratory problems and trigger smog production. The paint's base is polysiloxane, a silicon-based polymer. Embedded in it are spherical nanoparticles of titanium dioxide and calcium carbonate 30 nanometres wide. Because the particles are so small, the paint is clear, but pigment can be added. The first paint to go on sale will of course be white."
I've been eating a lot of onions lately.. I NEED this paint!
"It's too bad that stupidity isn't painful." - Anton LaVey
This will come in handy in the bathroom
... but somebody was going to say it ...
I know
I seem to recall TO2 being a fairly nasty chemical to produce, using lots of Chlorine in production, etc. (Of course, high-school chem was a while back...) Is using the paint a net benefit to the environment? If not, what's the point?
According to the article, after the carbonate runs out after about 5 years in a heavily polluted city, "the titanium dioxide will continue to break down NOx, but the acid this produces will discolour the paint."
Doesn't sound very good.
HCG 50a = 2MASX J11170638+5455016
11h17m06.4s +54d55m02s
In goes noxious gas (pun intended) and out comes a weak acid. Put a ring of limestone gravel or pavers around the base of the building and even that would be neutralized.
Of course the bigger question is if this paint and other materials like it are cheaper then catching the gasses closer at their sources, or at least ensuring those sources aren't so close to folk's lungs and other living creatures not appreciative of such.
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
If you read the article you'll see a nice and practically useless image where it shows that NOx is broken down to harmless stuff like water and oxygen. Don't ask me HOW exactly. Anyways, once the calcium carbonate runs out, the nitric acid will not be nuetralized. ( good read up on a chem textbook regarding bases ( like calcium carbonate ) and acids, especially how they affect eachother ) Having a whole load of acid building up inside your paint isnt a good thing but according to the article it will just discolour the paint. While the Titanium Oxide will happily continue to absorb more NOx and thus create more acid.
So basically, nowadays you have to paint once every 5 years because the smog attacks the paint. Now you have to paint once every 5 years because the paint attacks the smog.
Hate me!
Really, the places that have the highest concentration of vehicles - downtowns - seem to be almost entirely cement, glass, and brick. Out in the suburbs there's houses with paint on them, but there's not much pollution out there...unless you live in southern California. Cement might actually be more useful because there are more cement surfaces than painted surfaces in high-density parts of town.
The definition of a liberal: I may disagree with what you have to say, but I'll fight for your right to say it
The Titaninum oxide is a catalyst, so it is not consumed. The calcium carbonate is just there to neutralize the acid that is produced on the catalyst. So, the paint will never get sauruated with acids. I'll bet that they catalyst will keep working without the calcium carbonate & that the resulting nitric acid will just wash off, probably into some nearby concrete, which aso has a lot of calcium carbonate to neutralize the nitric acid. Besides, a little nitric acid isn't all that bad as a pollutant... you can safely wash it down the drain.
Think global, act loco
Naturally, you wouldn't use this paint on things that it would corrode. I don't think this is something to lose sleep over- the paint would have its recommended uses and warnings on the label of the paint can.
I agree with some of the other posts before me though: is the benefit of reduced nitrous oxide in the air outweighed by the other possible environmental dangers? I hope this goes through a lot of testing by independent groups before it hits the market.
At least it will be obvious when a new coat is needed.
I can see this stuff being required by ordnance in cities, especially places like Los Angeles and Beijing, where air pollution is a major issue.
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The titanium dioxide is a catalyst. It catalyzes a reaction between NO2 and water to produce nitric acid, HNO3. This reacts with calcium carbonate, CaCO3 (basically chalk) in the paint to produce water, carbon dioxide, and calcium nitrate:
CaCO3 + 2HNO3 -> H2O + CO2 + Ca(NO3)2.
The titanium dioxide is not consumed in the reaction, but the chalk is, and when it runs out, your paint fills up with nitric acid, which is not good. However, the reaction that causes the formation of nitric acid happens at a slower rate on its own, it is one source of acid rain.
Calcium nitrate is not noxious; it's basically fertilizer. However, too much nitrate runoff will cause problems with excessive algae growth in water, which can drop the oxygen level low enough to kill fish. Just the same, there's a lot more nitrate runoff from farmers and lawns than you're likely to get from this stuff.
It's interesting to note that an experimental technology involving the use of very fine titanium dioxide powder has been selected to purify water. The water is recirculated in a fountain so that it is exposed to lots of light- ultraviolet catalyzes the decomposition of select contaminants in the presence of the otherwise inert titanium dioxide, producing non-toxic byproducts. It's CHEAP, safe, and effective- but nobody wants to do it, since the technology is still in the experimental phase. Company XYZ isn't willing to pay $millions to try it when there are proven (if more expensive) techniques for doing essentially the same thing.
And I'm a firefighter, too. And a chemist. Too many hats to wear these days.
Yeap, SUVs are a political issue not an enviromental one. Apparently the standard of living in the US is such that people no longer have to worry about their own lives, they can now spend all their time telling other people what they should be doing.