Studies of Photocatalytic Degradation of Trace-Level MC-LR in Water on Thin Film of Titanium Dioxide

Abstract:

MCs are produced by cyanobacteria and cause concerns in potable water due to toxicity. Conventional treatments are poor at removing MCs. In the present study, the photocatalytic degradation of MC-LR was conducted using nano-TiO2 thin film, prepared by sol-gel and dip-coating method, with UV 365nm irradiation. According to analysis results from solid-phase extraction combined with HPLC method, the trace-level MC-LR is easily to be removed by photocatalytic system. The degradation efficiency of MC-LR is influenced by the pH conditions, initial concentration due to adsorption of MC-LR on TiO2 thin film. The maximum initial rate of photocatalytic degradation occurs at pH 4 and over 95% of 20μg/L MC-LR is decomposed within 120min. The kinetic equations and parameters revealed that degradation reaction of trace level MC-LR, which depicted by pseudo first order kinetics process in appearance, was in accordance with Langmuir-Hinshelwood kinetics model well, the corresponding rate constant k and Langmuir adsorption constant K were determined to be 19.72μg/l·min-1 and 6.57×10-4l/μg, respectively.

• Periodical: Solid State Phenomena (Volumes 121-123)
• Pages: 951-954
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.121-123.951
• Online since: March 2007
• Authors: X.G. Feng, F. Rong, Tao Wei, Chun Wei Yuan
• Keywords: MC-LR, Photocatalytic, Titania (TiO₂), Trace-Level

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