Abstract
PURPOSES : About 35% of air pollutant is occurred from road transport. NOx is the primary pollutant. Recently, the importance of NOx removal has arisen in the world. $TiO_2$ is very efficient for removing NOx by photocatalytic reaction. The mechanism of removing NOx is the reaction of photocatalysis and solar energy. Therefore, $TiO_2$ in concrete need to be contacted with solar radiation to be activated. In general, $TiO_2$ concrete are produced by substitute $TiO_2$ as a part of concrete binder. However, 90% of $TiO_2$ in the photocatalysis can not contacted with the pollutant in the air and solar radiation. Coating and penetration method are attempted as the alternative of mixing method in order to locate $TiO_2$ to the surface of structure. METHODS : The goal of this study was to attempt to locate $TiO_2$ to the surface of concrete, so we can use the concrete in pavement construction. The distribution of $TiO_2$ along the depth were confirmed by basing on the comparison of $TiO_2$ compare by using the EDAX(Energy Dispersive X-ray Spectroscopy). RESULTS : $TiO_2$ were distributed within 3mm from concrete surface. This distribution of $TiO_2$ is desirable, since the $TiO_2$ induce photocatalysis are located to where they can be contacted with the air pollutant and solar radiation. CONCLUSIONS : Nano size $TiO_2$ is easily penetration in the top 3mm of concrete surface. By the penetration $TiO_2$ concrete can be produced with the use of only 10% of $TiO_2$, by comparing the mixing types.
