Photocatalytic pavements with epoxy-bonded TiO₂-containing spreading material

Abstract

Titanium dioxide (TiO₂) is a photocatalyst which can accelerate the oxidation of nitrogen oxides (NOx) and other pollutants under ultraviolet (UV) radiation. In this study, a new method to coat TiO₂ onto asphalt pavements was developed with the aim to enhance the NOx decomposition efficiency and durability of the coating material for asphalt pavements. In this method, pulverized TiO₂-cement mortar is used as the spreading material, which is bonded to asphalt pavement surface by epoxy resin. The composition of the TiO₂-cement mortar was optimized in terms of its mechanical properties. The long-term NOx degradation efficiency, abrasion resistance, and skid resistance of the spreading material were measured after it was subjected to 300 min polishing by the advanced Aachen Polishing Machine (APM). It was concluded that durable NOx degradation efficiency can be achieved by the developed method and the method is feasible for practical implementation.