Air Pollutant Removal Paving Block

After a lengthy research period by the Hong Kong Polytechnic University, Air Pollutant Removal Paving Block has been successfully invented. The results demonstrated that air cleaning agent such as titanium dioxide can be incorporated into the technique of producing concrete paving blocks made with local wastes to remove air pollutants such as nitrous oxides (NOx) by at least 20 %.

Mechanism of decomposition of air pollutants

Photocatalytic titanium dioxide is energized by UV and accelerates the decomposition of organic particulates and airborne pollutants such as nitrous oxides (NOx).

The catalysed compounds break down into oxygen, water, sulfate, nitrate and other molecules that are not harmful to the environment.

Japanese Experience

Quoted from Michael Chusid, Concrete Decor Archive
"It is also being used to reduce air pollution. In one study, photocatalytic paving decomposed 15 percent of the nitrous oxide released by cars traveling the roadway and was more effective, in this regard, than planting trees on both sides of the roadway. "

Supporting Data

* C.S. Poon and E. Cheung. NO removal efficiency of photocatalytic paving blocks prepared with recycled materials. Construction and building materials , in press.