Title: Pervious Concrete with Titanium Dioxide as a Photocatalyst Compound for a Greener Urban Road Environment

摘要

The United States is facing the problem of trying to control air pollution from vehicle emissions,especially in growing urban areas. This study innovatively investigates applying thephotocatalytic effect of titanium dioxide (TiO2) onto pervious concrete pavement to removesome of these pollutants from the air, so that pervious concrete pavement can be installed for twosustainable applications: storm water management and air pollutant removal. The photocatalyst,TiO2, activates with UV radiation to oxidize air pollutants, such as nitrogen oxides (NOx) andvolatile organic compounds (VOCs). This study compared different methods to apply TiO2 ontothe surface of pervious concrete and measured the photocatalytic activity of the concrete, theinfiltrating characteristics of the pervious concrete, and its ability to withstand environmentalweathering. A brief analysis on each application method with respect to material cost is alsopresented. High pollutant reductions were seen with a driveway protector mix, a commercialwater-based TiO2 preparation, TiO2 in water, a cement-water slurry with low cementconcentration, and the commercial PURETI coating. It was found that nitrogen oxide (NO) wasefficiently removed with each of these treatments, while VOCs displayed more variability inremoval efficiency. The PURETI coating had the least effect on reducing the infiltration rate ofthe pervious concrete. The driveway protector mix had the highest resistance against deicingchemical and freeze-thaw testing. When pervious concrete was compared to traditional concrete,pervious concrete showed higher NO reductions, whether the sample had TiO2 coating on it ornot.