Abstract:
ABSTRACTOwing to the potential toxicity of some dyes and drugs and their visibility in surface waters, removal and degradation of them have attracted considerable worldwide attention. A wide range of approaches have been developed for such purpose. Nano SnO2 photocatalyst supported in polymer as a thin film was used on the degradation of organic dyes and phamcutical waste Ciprofloxacin and Acridine orange dye which have wide range of applications. In this study, The results showed that SnO2 thin film photocatalyst exhibited the best photodegradation efficiency of Ciprofloxacin and Acridine orange, so it was chosen to decolorize them. The reusability of SnO2 thin film also was tested by applying for multi uses on its degradation process. The operational parameters were investigated in order to be optimized to the best conditions which result in complete removal of organic pollutants and pharmcutical pollutants from aqueous solution. It was found that the degradation of them depends on several parameters such as irradiation time, initial pollutants concentration, pH of the pollutants solution, the presence of electron acceptors such as hydrogen peroxide and concentration and the energy of the applied radiation. The effect of presence of other substances such as inorganic ions was also examined. Kinetic studies of phototcatalytic degradation of Acridine orange and Ciprofloxacin were carried out. The apparent rate constant (kapp) of the two reactions was estimated according to Langmuir-Hinshelwood (L-H) equation. The results obtained showed that SnO2 is the most active photocatalyts for acridine orange and Ciprofloxacin degradation. SnO2 photocatalyst was used through five successive batches and close results were obtained. The optimum conditions of photocatalytic degradation of the dye and drug are as the following: Percent degradation was increased with irradiation time. The degradation efficiency decreased as the initial concentration of the two dyes increased. The optimum pH of the solution was 3 for Ciprofloxacin and 11 for Acridine orange. The degradation efficiency was maximum at H2O2 concentration of 0.01M added to Ciprofloxacin solution while 0.1M was the best H2O2 concentration should be added to Acridine orange. The maximum catalytic degradation of Acridine orange was achieved upon applying UV light 254nm. Apparent rate constant (kapp) of photocatalytic degradation of 5×10-5 M Acridine orange utilizing SnO2 thin film was estimated and found to be 0.0116 min-1 while that for photocatalytic degradation of 10×10-5 M Ciprofloxacin utilizing SnO2 thin film was 0.0082 min-1.Key words:Photodegradation, nanoparticle, Acridine orange dye, Ciprofloxacine, photocatalytic thin film