Aqueous degradation kinetics of pharmaceutical drug diclofenac by photocatalysis using nanostructured titania–zirconia composite catalyst

Abstract

Diclofenac (DCF) is an anti-inflammatory pharmaceutical drug, and its presence in a trace amount in waste water makes severe environmental pollution. The degradation of DCF was investigated by a photocatalytic process in presence of ultra violet irradiation at room temperature using titania and titania-zirconia nanocomposite catalysts in a batch reactor. The composite catalyst was prepared by sol-gel method and characterized by X-ray diffraction, transmission electron microscopy as well as BET surface area analyzer. The effect of various process parameters such as catalyst loading, initial concentration of DCF and pH of the experimental solution was observed on the degradation of DCF. The titania-zirconia nanocomposites exhibited reasonably higher photocatalytic activity than that of anatase form of titania without zirconia. The maximum removal of DCF of about 92.41 % was achieved using Zr/Ti mass ratio of 11.8 wt% composite catalyst. A rate equation was proposed for the degradation of DCF using the composite catalyst. The values of rate constant (k c ) and adsorption equilibrium constant (K 1 ) were found to vary with the catalyst content in the reaction mixture.

Paracetamol degradation and kinetics by advanced oxidation processes (AOPs): Electro-peroxone, ozonation, goethite catalyzed electro-fenton and electro-oxidation

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Adsorption of pharmaceuticals onto activated carbon fiber cloths – Modeling and extrapolation of adsorption isotherms at very low concentrations

“…The contamination of aquatic systems by pharmaceutical residues is widely reported and constitutes a growing concern and risk for the environment and human health (Das et al, 2014;Gamarra et al, 2015;Huerta-Fontela et al, 2011). For instance, Loos et al, (2009) detected diclofenac in 83 % of their samples in European rivers.…”

Recent advances in removal of pharmaceutical pollutants in wastewater using metal oxides and carbonaceous materials as photocatalysts: a review

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