Application of Nano- TiO2 Used in Road Engineering and its Long-Term Decomposition Effect

With the widely research of nano-TiO2, researchers have found another way of managing air quality. As an excellent photocatalyst material, nanometer titanium dioxide has begun to be used in road engineering in recent years. In this paper, substantial gas decomposition tests are performed utilizing the self-designed sealed container and UV aging box. At first, the catalytic efficiencies of nanometer titanium dioxide dispersed in silane solvent and in asphalt mixture were compared. The results show that nanometer titanium dioxide is able to decompose CO, HC and NO after being dispersed in silane solvent and asphalt mixture. To achieve the same catalytic efficiency, the amount of the nanometer titanium dioxide dispersed in silane solvent is much less than that in asphalt mixture. For asphalt mixture, high void fraction may mean high catalytic efficiency. Then the long-term decomposition of asphalt mixture was discussed. The asphalt mixture still has good catalytic decomposition effect after six months. The catalytic effect of asphalt mixture does not diminish over time and the effect of decomposing HC has improved after six months. At last, for cement paint, the catalytic effect of decomposing NO and HC does not diminish over time, but the effect of decomposing CO reduces.