Determination of photocatalytic activity of P25 and kronoclean concrete by degradation of methylene blue

Since the beginning of time, Titanium Dioxide (TiO2) has been used in widespread applications ranging from food additives to cosmetics. Recently, the application of TiO2 photocatalyst has been apparent with the discovery of water splitting on TiO2 electrodes. TiO2, usually in the rudimentary form of Rutile, Anatase and Brookite, have been altered to produce a new line of products. This study aims to determine the effectiveness of two TiO2 compounds, namely P25 and KRONOClean, in relation to their degradation of aqueous methylene blue solution over time. Cylindrical TiO2 concrete samples with varying TiO2¬-Cement content were prepared and place in a beaker containing aqueous methylene blue solution. The samples were exposed to both direct sunlight and office light respectively while keeping other variables constant. The effectiveness of the TiO2 compound was determined by assessing the absorption coefficient as a function of wavelength. The outcome of the study concluded KRONOClean at 5% ratio to be the most effective. In addition, the illumination of the sample under direct sunlight achieved a faster rate of decomposition. The findings were substantiated with the determination of the band-gap energy. The Kubelka-Munk model was used to determine the band-gap energy of the powdered TiO2 through its diffused reflectance. The optimal efficient TiO2-Cement ratio was discussed and the future development of the study was also mentioned.Bachelor of Engineering (Civil