Relevance of Photocatalysis prior to Biological Treatment of Organic Pollutants – Selection Criteria

Abstract

International audienceThe relevance of a photocatalytic pretreatment prior to a biological process for removal of organic pollutants was examined. Owing to the significant residual amount and toxicity, amitrole was not relevant. High mineralization allowed to remove bisphenol A and 2,4-dichlorophenoxyacetic acid. Isoproturon and diuron cannot be considered due to the slight evolution of chemical oxygen demand/ total organic carbon (COD/TOC) and average oxidation state during irradiation. After photocatalysis, the ratio of biological oxygen demand (BOD5)/COD remained below the biodegradability limit (0.4) for the rest of the molecules. A favorable COD/TOC trend (decrease during irradiation) was recorded for dimethoate and antibiotics. However, dimethoate and sulfamethoxazole seemed not pertinent due to the long time span for their removal. Since a decrease of toxicity was only recorded for tylosine, it can be selected for subsequent tests

Kinetic study of the degradation/mineralization of aqueous solutions contaminated with Rosuvastatin drug by Electro-Fenton: Influence of experimental parameters

“…The amount of oxygen required for the oxidation of the organic matter at 150 °C for 2h was quantified after oxidation with K 2 Cr 2 O 7 in acidic medium [61]. COD values were measured colorimetrically using DR/125 spectrophotometer (Hach company, USA).…”

An overview on the advanced oxidation processes applied for the treatment of water pollutants defined in the recently launched Directive 2013/39/EU

“…Isoproturon, diuron, and 17-alpha-ethinylestradiol were totally converted after 3-5 h using three UV lamps and combining a cellulose fiber, TiO2 and SiO2 (Fourcade et al, 2012). Alachlor removal depended on both the irradiation time and the H2O2 concentration in a batch photocatalytic reactor where TiO2 nanoparticles were immobilized (Mahmoodi and Arami, 2010), while its poor degradation was obtained with an organic 2,4,6-triphenylthiapyrylium photocatalyst in a solar simulator (Gomis et al, 2012).…”

Treatment of statins drug (pravastatin and rosuvastatin) in water by electro-Fenton process: Kinetics of degradation/mineralization and optimization of experimental conditions for a biological post-treatment

“…Mineralization of solutions was followed by the reduction of chemical oxygen demand (COD) using the Lovibond ® Vario-MD200 Photometer. After oxidation with K 2 Cr 2 O 7 at an acidic pH, quantification of the amount of oxygen required for oxidation of the organic material was carried out at 150°C for 2 hours 37 . COD values have been measured colorimetrically using DR/125 spectrophotometer (Hach Company, USA).…”