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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
Sure this sounds like great news. Here comes the science...
:-)
What happens when the paint is saturated? Sure it works to a point, but will additional coats of paint over revitalize production, or are we looking at a long term problem when the paint fails and begins soaking up noxious chemicals that could leak and cause a really nasty effect on the environment? Furthermore, did anyone read this sentence in the article and become slightly shocked? "The acid is then either washed away in rain, or neutralised by the alkaline calcium carbonate particles, producing harmless quantities of carbon dioxide, water and calcium nitrate, which will also wash away."
So it either causes acid rain, or it cleans the environment?
This will come in handy in the bathroom
... but somebody was going to say it ...
I know
Could this paint also be applied directly on pollution sources, such as on the inside of car tail pipes or the inside surface of smoke stacks?
That would seem like a more logical place to apply this paint, though applying it to roads and other surfaces probably doesn't hurt, either.
In 2002, after 7000 square metres of road surface in Milan, Italy, were covered with a catalytic cement, residents reported that it was noticeably easier to breathe - with the concentration of nitrogen oxides at street level cut by up to 60 per cent.
None of the usual "20% decrease in XYZ, 30% lower levels of ABC", plain and simple "it makes a difference noticeable to people".
Interesting technology, but the "paint will begin to discolor after approximately 5 years" may discourage widespread deployment.
Visit CryptoGnome in his home.
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?
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.
It is worth noting that the NOx from smog already forms nitric acid, which sticks to surfaces. Nitric acid is very "sticky" in this regard, and when it rains or the humidity gets very high, it corrodes the surfaces on which it has been deposited. This occurs even without the catalyst. In effect, the new paint won't be a big change- nitric acid will continue to be deposited, but at a higher rate- and preferentially on surfaces with the catalyst, which has a modest amount of calcium carbonate to neutralize the product.
On the bright side, if calcium carbonate is used for neutralization, the calcium nitrate is actually fertilizer. Yum for the plants.
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!
Time is Nature's way of keeping everything from happening at once... the bitch.
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.
They mix in calcium carbonate to neutralize the acid. But the article says that the calcium carbonate runs out in about five years, and then the acid discolors the paint (and presumably corrodes whatever is under it).
The calcium nitrate will eventually run off into the nearest body of water, and excess nitrates in water cause algal blooms and can kill off fish. However, I doubt if the amount of nitrates from this source will be significant compared to the large amount of fertilizer runoff.
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.
Hey, and that crap they threw into gasoline, yup that was safe.
Asbestos was a really nice fire retardent material. Too bad it had a tendency to create dust that causes lung cancer.
And to cap it all off, let's have 3 cheers for air bags and anti-lock brakes. If you are a small-fry like my wife and myself, you too can be killed in a 10mph impact by a piece of safety equipment! Anti-Lock brakes, they actually increase breaking distance and if you pump them (like anyone over the age of 26 was trained to do) you are screwed.
You really start to understand why people in ages past were so resistant to change.
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
I used to work in a coal burning power plant where they are required to run catalytic scrubbers to remove some of the NO2 before releasing it. While walking above the boilers one day I inhaled a lungful of something noxious that about knocked me off my feet and the safety engineer later said it was probably an NO2 leak. It felt like a chemical burn in all my respiratory passages for days. Anyway that is an environment where NO2 gas is highly concentrated and the workers there could be partially protected by painting the offices, breakrooms, turbine rooms, etc. with this stuff.
Liberals call everyone Nazis yet they are the closest thing to it.
Racist manufacturers. :)
My favourite part of the article (with a different substance):
In 2002, after 7000 square metres of road surface in Milan, Italy, were covered with a catalytic cement, residents reported that it was noticeably easier to breathe - with the concentration of nitrogen oxides at street level cut by up to 60 per cent.
60% percent less nitrogen oxides in less than a year? Hell, coat my lungs with it. Even if if has to be reapplied every couple of years, it would be worth it to apply the cement version to streets, and roads and the paint version to buildings. Dunno about the whole discolouration thing, though.
Wonder how long it'll be now that we have photocatalytic paint before someone comes up with photovoltaic paint that can produce significant power? Even cooler if they could be combined.
Have you ever seen NO2? It's orange. It's a gas. It's an acid. It *is* smog. It's like the sixth most powerful acid of all acids or thereabouts (when mixed with water of course... producing nitric acid... H20 + NO2 --> H2NO3). The cool thing is that the right catalyst (cars have catalytic converters which do this, as well as get rid of CO) will turn it into harmless Nitrogen and Oxygen. The uncool part is that it's also easy to make, just mix Nitrogen and Oxygen (uh, like air) at high temperature and pressure (like in an engine).
The fact that the paint is trying to address environmental problems will probably make people have even greater worries about what chemicals it puts into the ground water etc..
People should realize that all paints and coatings end up in the environment.
I admit this is intriguing science. The most interesting thing about pollution reducing coatings to work, there will need to be a unique formula for each city. I live in a city where the worst pollution days happen in the dead of winter with temperature around 30 degrees farenheit. Other cities get bad during the heat.
It is an interesting science, but not a one size fits all science.
Please, do not spread this FUD.
.au only deploy above 60km/h because they expect the seatbelt to be doing it's job keeping the occupant in the seat in minor impacts. Airbags in the US deploy a lot slower because they can't predict whether someone is using a belt or not. Anyway, airbags only deploy so far into the cabin - make sure you're not hurtling unrestrained towards the windshield and you'll be fine (if a bit shaken / bruised).
;-)
If you are a small-fry like my wife and myself, you too can be killed in a 10mph impact by a piece of safety equipment!
Wear your damn seatbelt. Airbags in
Anti-Lock brakes, they actually increase breaking distance and if you pump them (like anyone over the age of 26 was trained to do) you are screwed.
Antilock brakes allow you to steer your way out of (and possibly avoid) an impending accident. Most people's reflexes are to keep pressing that brake pedal until you stop. Train yourself away from pumping the pedal - ABS can pump that pedal a lot faster than you can. They are also multi-channel, and can yield considerably more braking effort from each wheel than you, eg two wheels off the edge of the road on dirt. So unless you have four brake pedals in your car, you , by yourself, have very little chance of getting a shorter braking distance than your antilock brakes can. (Yes, special circumstances apply).
I would buy the car with ABS and airbags, because those two technologies would significantly improve my chances of survival in day-to-day driving.
And here ends my little rant for the day
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
As a firefighter, I have to ask the question of what happens when it burns. If all these toxins are intentionally captured into the paint, are they released when it burns? Would this mean that people will have even less time to escape from a fire?
New Scientist is reporting a story about a new paint that can absorb noxious gas.
I heard that Darl McBride got the first stocks of this to paint on the wall facing his desk.
it in some way offers an alternate reaction path that is more favorable. Some catalysts work by providing a surface to which the reactants stick. I suspect that is what is happening here since making microbeads of titanium dioxide would maximize the surface area and thus the potential catalytic effect. By definition catalysts are not used up in the reaction that they catalyse.
My only political goal is to see to it that no political party achieves its goals.
-Tupshin