Solar photocatalytic removal of herbicides from real water by using sol–gel synthesized nanocrystalline TiO2: Operational parameters optimization and toxicity studies

摘要: Abstract A comparative study of the photocatalytic activity two different TiO 2 catalysts in solar oxidation, mineralization and detoxification waters containing herbicides 2,4-dichlorophenoxyacetic acid (2,4-D), bentazon toxic intermediates was performed a pilot plant scale photoreactor. Commercial (Degussa P25) synthesized by citrate sol–gel method (ECT-1023t) were selected as photocatalysts. The optimal basic operational parameters to eliminate these established for both at laboratory scale. ECT-1023t showed better than commercial Degussa P25 with real water natural pH (6.8–7.8) without any additive. toxicity treated solutions evaluated using Microtox test based on inhibition bioluminescence bacteria Vibrio fischeri . effect main intermediate 2,4-D, 2,4-dichlorophenol (2,4-DCP), higher parental herbicide. Acute 2,4-D (2,4-DCP) reduced during treatment photocatalyst. Longer times necessary obtain similar results when No inhibitory growth herbicide its photoproducts observed either photocatalyst irradiated samples collected predetermined an initial concentration 0.1325 mM