Abstract
A photocatalytic detoxification of phenol and 1-naphthalene acetic acid was carried out using two different photocatalysts, Degussa P25 and Hombikat UV100. The degradation reaction was compared by using two sources of UV-light, sunlight and UV-Lamp. All degradation reactions were performed after first optimising the pH and catalysts concentrations. The optimal initial pH was found to be 5.0 for both catalysts. The optimal concentrations for Degussa P25 and Hombikat UV100 occurred at 7g/l and 10g/l, respectively. The degradation rate of 1-NAA and phenol is higher when using sunlight, compared to the artificial UV-light (UV-Lamp) for both
photocatalysts Degussa P25 and Hombikat UV100.
A complete degradation of 1-NAA was achieved after 5 hours irradiation of Degussa suspension under direct sunlight while 23.43ppm of compound concentration was still in Hombikat suspension after 8 hours irradiation time. Phenol was not completely degraded even after 8 hours irradiation under natural and artificial UV-light by either catalyst. The degradation rate of 1-NAA is faster than that of phenol using the two sources of UV-light. Degussa P25 is the more efficient photocatalyst in degradation of 1-NAA and
phenol using direct sunlight and artificial UV lamp. About 90% TOC of RASCO wastewater was completely mineralized within 8 hours of
irradiation using the two-photocatalyst types at moderate suspension pH 6.55. Therefore, the solar detoxification process appears to be a good technique to treat the organic load of RASCO effluent treatment plant.