Nitric Oxide Reduction by Applying Various Coating Methods of TiO2 on Cementitious Materials

Abstract

Nitric oxide generated from various sources like car combustion is one of the most surrounding pollutants. Titanium dioxide considered an environmentally friendly active photocatalytics that can be used with building materials safely and effectively to react with nitric oxides in the presence of UV radiation from sunlight.To study the possibility for the reduction of air pollutants two strategies were adopted. First one included mixing of micro particles of TiO2 with cement paste in two percentages: 3% and 6%. In the second one mortar substrates were coated with micro TiO2 (mT) aqueous solution by either dipping or spraying coating method. A laboratory test procedure was adopted to assess the performance of the prepared photoactive specimens. The specimens were subjected to NO gas and there efficiency in gas removal was monitored with time.Results showed that coating strategy was more effective than mixing strategy in term of gaseous pollutants removal. The comparison between the two coating methods showed that the dipping method reached 98.08 % removal capacity and was better than spring method which reached 87.69 % only.