Paint That Soaks Up Noxious NOx Fumes Thanks to Nanotechnology

Millennium Chemicals is about to release Ecopaint, a revolutionary new paint that can soak up nitrogen oxide NO_x, gases. NO_x gases are produced by car exhaust emissions and manufacturing operations and are a pollution source that leads to smog as well as respiratory problems.

Ecopaint is claimed to be able to effectively soak up NO_x gases for 5 years. Trials of a similar coating in Milan lead to NO_x levels being reduced by 60 per cent at the street level, making the air noticeably easier to breathe.

The paint contains spherical nanoparticles of titanium dioxide (TiO₂) and calcium carbonate (CaCO₃) in a silicon-based polysiloxane polymer. The nanoparticles are 30nm in diameter and the resultant paint clear, so pigments can be added to give it colour.

The polysiloxane polymer is porous, and allows the NO_x gases to infuse and adhere to the titanium dioxide particles. Exposure to ultraviolet radiation from sunlight converts the NO_x to nitric acid (HNO₃), which is neutralised by the calcium carbonate. This interaction produces carbon dioxide (CO₂), water and calcium nitrate (Ca(NO₃)₂) which are harmlessly washed away.

Posted February 5^th, 2004