Preferred Abstract (Original):
. This work describes a photodegradation catalyst, for water organic contaminants in visible light, based on curcumin (a natural dye) sensitized TiO2 (anatase) nanoparticles. Phenazopyridine (a pharmaceutically active gradient) was used as a contaminant. A 400 nm, and shorter, cut of filter was used to confirm only visible light was used in photodegradation process with no UV radiation. The catalyst system was characterized by electronic absorption spectroscopy and XRD. The particle size forthe catalyst nanaprticles was calculated using Scherrer equation and found to be ~45 nm in average. Different reaction parameters were studied, such as effect of contaminant concentration, amount of loaded catalyst, and pH value on the photodegradation rate. Turn number (T.N.) and quantum yield (Q.Y.) values were calculated for comparative assessment of the catalyst effeciency. The results show the ability of curcumin dyes to sensitize TiO2 anatase nanoparticles in photodegradation phenazopyridine under visible radiation.