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Researchers at the University of California, Riverside, say they have demonstrated that a cheap roof coating can devour smoke
Form contaminants that, if widely adopted, can remove a large amount of air pollution from Southern California every day.
In laboratory experiments, engineering students found that ordinary clay roof tiles were sprayed with titanium dioxide, removing nitrogen oxide pollution from the air from 88% to 97%.
Nitrogen oxide is the gas produced by fuel combustion, discharged from automobile exhaust pipes, industrial chimneys and power plants, reacting in the sun, forming ozone, which is the main component of smoke.
However, a white compound, titanium dioxide, breaks down these pollutants into compounds that are less harmful.
The researchers calculated that if 1 million roofs were covered with smog,
They can remove 21 tons of nitrogen oxide from the air every day.
This is about 4% of the daily emissions of about 500 tons of nitrogen oxides from the California Southern Coast air basin, the largest smog area in the United States, including densely populated areas such as Los Angeles and Orange, riverside and San Bernardino County.
"By removing one of the components in a reaction that produces ozone or smoke, we can have some impact on improving air quality," Kawai Tam said . ", A lecturer in the Department of Chemistry and Environmental Engineering at the University of California Riverside, who helped oversee research projects completed by undergraduate students earlier this year.
The results are encouraging, said Tam, because they show that even a light coating of titanium dioxide can be effective.
It only takes about $5 to handle existing average roof tiles
The size of the house, she said.
This is not the first study to quantify air.
The purification capacity of titanium dioxide, this compound is common in paint, sunscreen, cosmetics and other consumer goods.
For example, a study published last year found that titanium dioxide was installed on a city street in the Netherlands --
Coated paving bricks reduce nitrogen oxide air pollution by 45%.
While titanium dioxide tiles are already commercially available, they are expensive and few studies have examined how effective they are in controlling pollution, Tam said.
In an experiment at the University of California, Riverside, the researchers
They build coated roof tiles in miniature atmospheric interiors with wood, Teflon and PVC pipes.
They will pump the chamber full of nitrogen oxides and use UV rays to simulate sunlight.
Then they measured the pollution concentration and found that they were around 20-minute period.
Tam said the next step could be to test the smoke-
The cutting coating performs well in the real world and whether it can be produced in a variety of colors suitable for home applications.