Photocatalytic Degradation of High Concentration Aqueous Solutions of Ketoprofen: Adsorption, Reaction Kinetic and Product Studies Article uri icon

abstract

  • The photocatalytic degradation of ketoprofen, a non-steroidal anti-inflammatory medication, with concentrations up to 80 ppm was studied using TiO2 Evonik-P25 as catalyst, UV radiation and constant flow of oxygen. Ketoprofen adsorption experiments under dark conditions were also carried out with the aim to get information about the interaction between ketoprofen and catalyst surface. Adsorption–desorption equilibrium was reached in 30 min of interaction. According to Langmuir isotherm, the maximum adsorption capacity of the organic molecule on the surface of TiO2 is 0.0672 mMoles KTP g−1 TiO2 and the adsorption constant is 1.771 L mM−1. Experimental results in terms of photocatalytic degradation indicate a complete mineralization of ketoprofen molecule after 6 h of reaction. Experimental results also indicate that the initial reaction rate of the photocatalytic degradation of ketoprofen can be modeled by the Langmuir–Hinshelwood–Hougen–Watson reaction rate equation. The kinetic constant and adsorption parameters of the LH–HW equation are 0.14 min−1 and 20.72 mM−1 respectively. Chemical analysis of reaction samples by HPLC, TOC, and UV–vis spectroscopy indicated that ketoprofen is mineralized via formation of hydroxy benzophenone, benzoic acid, hydroquinone, catechol, benzoquinone, benzene triol and phenol in a series–parallel reaction pathway. © 2022, The Author(s), under exclusive licence to Springer Science Business Media, LLC, part of Springer Nature.
  • The photocatalytic degradation of ketoprofen, a non-steroidal anti-inflammatory medication, with concentrations up to 80 ppm was studied using TiO2 Evonik-P25 as catalyst, UV radiation and constant flow of oxygen. Ketoprofen adsorption experiments under dark conditions were also carried out with the aim to get information about the interaction between ketoprofen and catalyst surface. Adsorption–desorption equilibrium was reached in 30 min of interaction. According to Langmuir isotherm, the maximum adsorption capacity of the organic molecule on the surface of TiO2 is 0.0672 mMoles KTP g−1 TiO2 and the adsorption constant is 1.771 L mM−1. Experimental results in terms of photocatalytic degradation indicate a complete mineralization of ketoprofen molecule after 6 h of reaction. Experimental results also indicate that the initial reaction rate of the photocatalytic degradation of ketoprofen can be modeled by the Langmuir–Hinshelwood–Hougen–Watson reaction rate equation. The kinetic constant and adsorption parameters of the LH–HW equation are 0.14 min−1 and 20.72 mM−1 respectively. Chemical analysis of reaction samples by HPLC, TOC, and UV–vis spectroscopy indicated that ketoprofen is mineralized via formation of hydroxy benzophenone, benzoic acid, hydroquinone, catechol, benzoquinone, benzene triol and phenol in a series–parallel reaction pathway. © 2022, The Author(s), under exclusive licence to Springer Science%2bBusiness Media, LLC, part of Springer Nature.

publication date

  • 2022-01-01