What is Digg?52 Comments
- op12, on 10/12/2007, -2/+41When it's full, the building develops a hacking cough.
- Otto, on 10/12/2007, -1/+18The material never gets full. Basically it's porous enough to allow the gasses in, along with water (like normal cement is). Titanium dioxide in the cement, along with UV light from the sun, breaks apart water. The resulting H and OH particles are very reactive and break apart the various pollutants into much less harmful stuff. TiO2 is also easy to make/find in nature, and so on. Cheap enough to use in paint, for example. It also causes rapid oxidization of pretty much anything organic directly, so it's quite useful for most things with carbon in them.
It's not useful to break apart water by itself (for, say, a hydrogen based economy), because the reaction requires UV light (which we don't get a lot of from the sun... only about 4% of total light), and also because it's not particularly efficent at it anyway. But it's good enough for this sort of thing. If we wanted a hydrogen economy from water, then there's better ways. For example, indium-tantalum-oxide doped with nickel does the same thing using visible light, but the efficency is total crap. There's better catalysts, but so far nothing extraordinary along these lines. Lots of scientists are, of course, working on it. - dbalaski, on 10/12/2007, -1/+18interesting enough- what happens when the building's material is full?? what is the strength of the material then? what about its disposal ????
- johndi, on 10/12/2007, -0/+15Just give it a coating of titanium dioxide paint. Titanium dioxide is so safe it's used as a food dye, but still breaks up pollution. Not that I would eat the paint.
http://www.newscientist.com/article.ns?id=dn4636 - nmap, on 10/12/2007, -0/+11This is not adsorption, it's catalysis.
Both article and title are misleading. - LeftistPersona, on 10/12/2007, -0/+9the question is how expensive is this cement?
- thedonga, on 10/12/2007, -1/+10interesting but it looks to me like the byproduct of this chemical reaction, nitric acid, is just as harmful...maybe not to the air quality, but definitely to the ground water. 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.
"The chemical compound nitric acid (HNO3), otherwise known as aqua fortis or spirit of nitre, is a colorless, corrosive liquid, a toxic acid which can cause severe burns. If the solution contains more than 86% nitric acid, it is referred to as fuming nitric acid, and can be separated into two kinds of fuming acids, white fuming nitric acid and red fuming nitric acid."
In addition:
Potential Health Effects of Calcium Nitrate
----------------------------------
Inhalation: Causes irritation to the respiratory tract. Symptoms may include coughing, shortness of breath.
Ingestion: Causes irritation to the gastrointestinal tract. Symptoms may include nausea, vomiting and diarrhea.
Skin Contact: Causes irritation to skin. Symptoms include redness, itching, and pain.
Eye Contact: Causes irritation, redness, and pain.
One evil for another evil....the solution is not to produce as much exhaust!!!! - ThinkBox, on 10/12/2007, -1/+8Pave over a tree to save a tree...
- we will have some confused environmentalists! - inactive, on 10/12/2007, -0/+6titanium dioxide is also useful for keeping a building clean by just using the sun's energy to oxidize dirt particles... its really cool stuff
- burke, on 10/12/2007, -0/+6My guess would be somewhere in the 'very' range.
- SpaceDreamer, on 10/12/2007, -1/+6It doesn't absorb. It has a coating that helps convert the gases into less harmful ones ( by catalysis ). The title is wrong. It's scary that they made that mistake on a website dedicated to science...
- Otto, on 10/12/2007, -0/+5smokester: TiO2 is a catalyst. It doesn't get used up in the reaction. Although it's possible that whatever the non-pollutants are, they might reduce the porousness of the material. Still, seems likely that it would last a long time. And the surface TiO2 would last forever.
- samdu, on 10/12/2007, -1/+6"the question is how expensive is this cement?"
Why would anyone digg that down? Monetary costs should ALWAYS be considered. It doesn't matter how good an idea is if you can't pay for it. - Otto, on 10/12/2007, -0/+3"interesting but it looks to me like the byproduct of this chemical reaction, nitric acid, is just as harmful...maybe not to the air quality, but definitely to the ground water."
Most naturally occuring nitric acid comes from rain, where NO2 has reacted with water to make it. It then falls out of clouds. In groundwater, it reacts with natural ammonia sources to form ammonium nitrate, which is both an explosive and a component of virtually all good fertilizers. Plants eat it.
I'm not saying that adding tons of nitric acid to the water table is a good idea, but it's not nearly as terrible as you seem to think. - inactive, on 10/12/2007, -0/+3Yeah, it sounds more like the top layer reacts with the pollutants to create...well, non-pollutants
If this is the case they'll probably need a fresh layers every few years or something, wonder what the installation/upkeep costs of this are - deepsub, on 10/12/2007, -0/+3Catalytic converter concrete.
Neat.
dugg - sapo916, on 10/12/2007, -0/+3Because we all know that usually your house is surrounded by spot-free Air.
- YesWorld, on 10/12/2007, -0/+3For a more in-depth article on catalytic cement and concrete products coated with titanium dioxide:
http://digg.com/science/Titanium_Dioxide_Cleans_Air_Pollution - twinklyJesus, on 10/12/2007, -0/+2Damn that George Bush and his army of insane Italian environmentalists!
- Egoist, on 10/12/2007, -0/+2Funny seeing an ignorant comment like that, especially from a Metabolife salesman.
- YesWorld, on 10/12/2007, -0/+2Sorry, it now seems the CNN story has been pulled. It was available this morning...
- thedonga, on 10/12/2007, -0/+2"I'm not saying that adding tons of nitric acid to the water table is a good idea, but it's not nearly as terrible as you seem to think."
good points otto. - Egoist, on 10/12/2007, -0/+2The ANSA article I read yesterday said that they're expected to sell it for 1euro/kilo, which is about 10 times the cost of normal cement.
Here's the english version:
http://www.ansa.it/main/notizie/awnplus/english/news/2006-05-16_1161495.html - slackbuster, on 10/12/2007, -0/+2Too bad they can't come up with one that sucks the contaminants out of water, I'm sure they'd be able to clean up the east river with all those cement shoes.
- armo, on 10/12/2007, -0/+2Another cement story for today http://technology.guardian.co.uk/weekly/story/0,,1771589,00.html?gusrc=rss
- inactive, on 10/12/2007, -0/+2Cement, like asphalt, is ground up and recycled (IIRC).
- masterofsw, on 10/12/2007, -0/+1Interestingly, the New Scientist link above mentions the Milan road test occurred in 2002.
- Kyderdog, on 10/12/2007, -0/+1If only that site has a few more ads...
- queefer, on 10/12/2007, -0/+1easier said than done.
- Kebert, on 10/12/2007, -0/+1All I read is "Eco-Vapoware Saves Planet"
- Egoist, on 10/12/2007, -1/+2It doesn't suck up anything, it causes a chemical reaction that breaks down the pollutants.
I think your posts needs more periods. - Morky, on 10/12/2007, -0/+1I heard of a better mechanism that actually replenishes itself by synthesizing sunlight. I forget what they're called: trias, troas, treos... something like that.
- inactive, on 10/12/2007, -0/+1Lungs absorb cigarette smoke but one may choose not to smoke to begin with
Stop making cars that pollute = solution for a lot of pollution - xt0ph3r, on 10/12/2007, -0/+1Except that it doesn't really absorb pollution, it breaks it down. It was a misleading article and title.
Stand down. You may release your shift key now. - DarthTurducken, on 10/12/2007, -3/+3If a tree falls on a hippie and no one's arond, does anyone care?
/sorry - rrbaker, on 01/15/2009, -1/+1Nice. Unfortunately I think this cement will simply be someday absorbed by common landfills instead of proper disposal methods.
- sandfish, on 10/12/2007, -1/+1Wow... pretty cool stuff.
- IncognitoCraven, on 10/12/2007, -0/+0Inaccurate, it's a coating (TiO2), and hopefully not an additive (that'd be wasteful).
Also note that curing cement/concrete absorbs CO2, of course the creation of
cement also produces *a hell of a lot* of CO2 (almost a tonne of CO2 per tonne of
lime). - RyomaNagare, on 10/12/2007, -0/+0Very well observed, the problem with this compound is that it limits its usage only to non armed roads, the concrete is basic in nature, and anything that lowers the PH, endangers the steel underneath.
so its basically unusable for buildings, bridges, or special roads..
it could be an interesting alternative for urban roads, but still you have to think about how low it takes to put a road in service, one of the disadvantages of concrete is that it takes 28 days (a little less with additives) to achieve its full strenght, while asphalt, is ready for use in a day tops. Lets consider costs, if the oil keeps rising its price, that means asphalt will become more expensive, and maybe then concrete will become an option again. - leva, on 10/12/2007, -0/+0So would an exhaust tip made out of titanium (exhaust tip because that is about the only part of the exhaust that even might be hit by the sun) help in converting the pollution into something else in conjunction with the catalytic convertor? Also how about a strip of this painted on the edge of a vehicles bumpers. Maybe even the whole upper part of a vehicle's exterior can be treated with TiO2. I see a problem with the nitric acid, but maybe a coating on top of the paint may help. Anyway just a though.
- nosmelc, on 10/12/2007, -0/+0Not to minimize the problem of calcium nitrate and nitric acid but MSDS often make anything seem dangerous. For example, read this portion of an MSDS for a very common substance.
Inhalation
Acute over exposure: Inhalation can result in asphyxiation and is often fatal.
Chronic overexposure: Chronic inhalation overexposure not encountered.
Skin Contact
Acute overexposure: Prolonged but constant contact with liquid may cause a mild dermatitis.
Chronic overexposure: Mild to severe dermatitis.
Ingestion
Acute overexposure: Excessive ingestion of liquid form can cause gastric distress and mild diarrhea.
Chronic overexposure: No effects noted.
Skin: None
Inhalation: Remove to fresh air; Provide artificial respiration; Provide oxygen.
Ingestion: None
Know what it is -- Water. - GregR, on 10/12/2007, -0/+0Yes, cement is a powder that is used to create concrete!
- Wildfire01, on 10/12/2007, -0/+0Technically wouldn't this be called concrete, not cement? ...pet peeve...rrg
- thadozaman, on 10/12/2007, -0/+0The Phoenix area is an ideal environment for ths type of technology.....Lots of Sun, Concrete, and Pollution....sounds like a No Brainer to me....
- inane, on 10/12/2007, -1/+0This fails to mention that less than 1% of all air pollution is from automobiles. It also fails to mention that enviro-nazis spew all kinds of misinformation in order to further their political agenda. There's a reason the founder of Greenpeace left the organization. Sounds like this company is capitalizing on environmental hysteria and using shaky science to make a buck.
- RodeoRobot, on 10/12/2007, -2/+1Great. Just what we need: contaminated cement filled with concentrated toxins.
- themamboman, on 10/12/2007, -1/+0now we can get rid of that worthless catalytic converter.
- JasonJenks, on 10/12/2007, -3/+0This sounds like an awesome idea! LETS WALK ALL OVER CANCER AND BREATHE IT IN FROM BELOW AND ABOVE!
- inactive, on 10/12/2007, -5/+1Yes! Teach those polluters and build your house out of this stuff. Move the pollution where you want it, right in your yard!
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