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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."
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?
When your house has absorbed all the noxious gasses it can handle, simply declare the neighborhood low-rent and move to a new subdivision painted with a fresh coat of Ecopaint!
grammar-lesson free since 1999. (rescinded - 2005)
Now, given the nature of the pain to absorb noxious chemicals, wouldn't we be seeing a problem of entire neighborhoods where the houses are literally big cubes of smog? Secondly, and this may be scientifically wrong, because it is just absorbing the NOx gases, not necessarily the smog itself, but isn't there a chance of discoloration of the paint after application? Would that beautiful white house become LA-brown within a couple years?
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.
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?
Paint is often supposed to protect surfaces from corrosion. In this case the paint collects nitrous oxide gasses and makes nitric acid, a very corrosive chemical. The paint is porous so we can have nitric acid within the paint, perhaps even close to the surface you want to protect. Now will that nitrous acid destroy whatever the paint was supposed to protect? Perhaps a good coat of different, non-porous paint below this paint will protect the surface, but if there are any deep scratches at least they may corrode much faster due to nitric acid.
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!
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
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.
What happens if you huff this paint? Can the vapors from the paint absorb noxious gases as well as the paint itself can, and if so, is it enough to cancel out the fact the paint fumes are themselves noxious? Inquiring minds want to know.
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
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.
Anti-lock breaks increase stopping distance over properly-executed threshold breaking, but I think it's terribly naive to claim that the general population is good at threshold breaking. Anti-lock breaks are a lot better for stopping than non-anti-lock breaks, if you lock your wheels. It's that whole static- versus dynamic-friction thingy.
And as for airbags and seatbelts causing injuries in crashes, it's true. They can. But guess what: it's statistically impossible for auto-makers to install saftey features that protect every possible driver from every possible impact. (well, the one saftey feature that would work is the "car-with-no-engine" feature. It never gets into accidents). So clearly, if airbags and seatbelts save more lives than they cost, they are worth having. And if you're so small that your airbag is always a danger to you, you can have it disabled (I have a friend, who is a dwarf, and her airbag is disabled, with a key, so that if a normal-sized person drives her car, it can be turned back on).
Just because a potential technology has a downside doesn't mean it's worthless and we should shun it. Nothing is free; just do the cost-benefit analysis and pick whichever has the best ratio.
-Tupshin