Heterogeneous Catalytic Ozonation of Pharmaceuticals: Optimization of the Process by Response Surface Methodology

Batch heterogeneous catalytic ozonation experiments were performed using commercial and synthesized nanoparticles as catalysts in aqueous ozone. The transferred ozone dose (TOD) ranged from 0 to 150 μM, and nanoparticles were added in concentrations between 0 and 1.5 g L<sup>−1</sup>, wi...

Full description

Saved in:
Bibliographic Details
Main Authors: Nikoletta Tsiarta, Wolfgang Gernjak, Hrvoje Cajner, Gordana Matijašić, Lidija Ćurković
Format: Article
Language:English
Published: MDPI AG 2024-10-01
Series:Nanomaterials
Subjects:
Online Access:https://www.mdpi.com/2079-4991/14/21/1747
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850196912939991040
author Nikoletta Tsiarta
Wolfgang Gernjak
Hrvoje Cajner
Gordana Matijašić
Lidija Ćurković
author_facet Nikoletta Tsiarta
Wolfgang Gernjak
Hrvoje Cajner
Gordana Matijašić
Lidija Ćurković
author_sort Nikoletta Tsiarta
collection DOAJ
description Batch heterogeneous catalytic ozonation experiments were performed using commercial and synthesized nanoparticles as catalysts in aqueous ozone. The transferred ozone dose (TOD) ranged from 0 to 150 μM, and nanoparticles were added in concentrations between 0 and 1.5 g L<sup>−1</sup>, with all experiments conducted at 20 °C and a total volume of 240 mL. A Ce-doped TiO<sub>2</sub> catalyst (1% molar ratio of Ce/Ti) was synthesized via the sol–gel method. Response surface methodology (RSM) was applied to identify the most significant factors affecting the removal of selected pharmaceuticals, with TOD emerging as the most critical variable. Higher TOD resulted in greater removal efficiencies. Furthermore, it was found that the commercially available metal oxides α-Al<sub>2</sub>O<sub>3</sub>, Mn<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, and CeO<sub>2</sub>, as well as the synthesized CeTiO<sub>x</sub>, did not increase the catalytic activity of ozone during the degradation of ibuprofen (IBF) and para-chlorobenzoic acid (pCBA). Carbamazepine (CBZ) and diclofenac (DCF) are compounds susceptible to ozone oxidation, thus their complete degradation at 150 μM transferred ozone dose was attained. The limited catalytic effect was attributed to the rapid consumption of ozone within the first minute of reaction, as well as the saturation of catalyst active sites by water molecules, which inhibited effective ozone adsorption and subsequent hydroxyl radical generation (<sup>●</sup>OH).
format Article
id doaj-art-a604d03811044bb3b46957bede4c50c2
institution OA Journals
issn 2079-4991
language English
publishDate 2024-10-01
publisher MDPI AG
record_format Article
series Nanomaterials
spelling doaj-art-a604d03811044bb3b46957bede4c50c22025-08-20T02:13:19ZengMDPI AGNanomaterials2079-49912024-10-011421174710.3390/nano14211747Heterogeneous Catalytic Ozonation of Pharmaceuticals: Optimization of the Process by Response Surface MethodologyNikoletta Tsiarta0Wolfgang Gernjak1Hrvoje Cajner2Gordana Matijašić3Lidija Ćurković4Catalan Institute of Water Research (ICRA)-CERCA, Carrer Emili Grahit 101, 17003 Girona, SpainCatalan Institute of Water Research (ICRA)-CERCA, Carrer Emili Grahit 101, 17003 Girona, SpainFaculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Ivana Lučića 5, 10002 Zagreb, CroatiaFaculty of Chemical Engineering and Technology, University of Zagreb, 10000 Zagreb, CroatiaFaculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Ivana Lučića 5, 10002 Zagreb, CroatiaBatch heterogeneous catalytic ozonation experiments were performed using commercial and synthesized nanoparticles as catalysts in aqueous ozone. The transferred ozone dose (TOD) ranged from 0 to 150 μM, and nanoparticles were added in concentrations between 0 and 1.5 g L<sup>−1</sup>, with all experiments conducted at 20 °C and a total volume of 240 mL. A Ce-doped TiO<sub>2</sub> catalyst (1% molar ratio of Ce/Ti) was synthesized via the sol–gel method. Response surface methodology (RSM) was applied to identify the most significant factors affecting the removal of selected pharmaceuticals, with TOD emerging as the most critical variable. Higher TOD resulted in greater removal efficiencies. Furthermore, it was found that the commercially available metal oxides α-Al<sub>2</sub>O<sub>3</sub>, Mn<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, and CeO<sub>2</sub>, as well as the synthesized CeTiO<sub>x</sub>, did not increase the catalytic activity of ozone during the degradation of ibuprofen (IBF) and para-chlorobenzoic acid (pCBA). Carbamazepine (CBZ) and diclofenac (DCF) are compounds susceptible to ozone oxidation, thus their complete degradation at 150 μM transferred ozone dose was attained. The limited catalytic effect was attributed to the rapid consumption of ozone within the first minute of reaction, as well as the saturation of catalyst active sites by water molecules, which inhibited effective ozone adsorption and subsequent hydroxyl radical generation (<sup>●</sup>OH).https://www.mdpi.com/2079-4991/14/21/1747heterogeneous catalytic ozonationpharmaceuticalshydroxyl radicalsresponse surface methodology
spellingShingle Nikoletta Tsiarta
Wolfgang Gernjak
Hrvoje Cajner
Gordana Matijašić
Lidija Ćurković
Heterogeneous Catalytic Ozonation of Pharmaceuticals: Optimization of the Process by Response Surface Methodology
Nanomaterials
heterogeneous catalytic ozonation
pharmaceuticals
hydroxyl radicals
response surface methodology
title Heterogeneous Catalytic Ozonation of Pharmaceuticals: Optimization of the Process by Response Surface Methodology
title_full Heterogeneous Catalytic Ozonation of Pharmaceuticals: Optimization of the Process by Response Surface Methodology
title_fullStr Heterogeneous Catalytic Ozonation of Pharmaceuticals: Optimization of the Process by Response Surface Methodology
title_full_unstemmed Heterogeneous Catalytic Ozonation of Pharmaceuticals: Optimization of the Process by Response Surface Methodology
title_short Heterogeneous Catalytic Ozonation of Pharmaceuticals: Optimization of the Process by Response Surface Methodology
title_sort heterogeneous catalytic ozonation of pharmaceuticals optimization of the process by response surface methodology
topic heterogeneous catalytic ozonation
pharmaceuticals
hydroxyl radicals
response surface methodology
url https://www.mdpi.com/2079-4991/14/21/1747
work_keys_str_mv AT nikolettatsiarta heterogeneouscatalyticozonationofpharmaceuticalsoptimizationoftheprocessbyresponsesurfacemethodology
AT wolfganggernjak heterogeneouscatalyticozonationofpharmaceuticalsoptimizationoftheprocessbyresponsesurfacemethodology
AT hrvojecajner heterogeneouscatalyticozonationofpharmaceuticalsoptimizationoftheprocessbyresponsesurfacemethodology
AT gordanamatijasic heterogeneouscatalyticozonationofpharmaceuticalsoptimizationoftheprocessbyresponsesurfacemethodology
AT lidijacurkovic heterogeneouscatalyticozonationofpharmaceuticalsoptimizationoftheprocessbyresponsesurfacemethodology