1. Diclofenac removal by simulated solar assisted photocatalysis using TiO2-based zeolite catalyst; mechanisms, pathways and environmental aspectsDionysios D. Dionysiou, Urška Lavrenčič Štangar, Sandra Babich, Hrvoje Kušić, Martina Biosic, Daria Juretic Perisic, Subhan Salaeh, Ana Lončarić Božić, 2016, original scientific article Abstract: The study explores the potential of immobilized TiO2-based zeolite composite photocatalyst (TiO2-FeZ)
made of commercial AEROXIDE TiO2 P25 and iron-exchanged zeolite of ZSM5 type (FeZ), for solar assisted
treatment of diclofenac (DCF), pharmaceutical included in the ‘‘watch list” during last prioritization in
water legislation by EU.
In this study the efficiency of applied photocatalytic treatment, solar/TiO2-FeZ/H2O2, of DCF water
solution was evaluated on basis of DCF removal and conversion kinetics, as well as the changes of
common parameters for assessing water quality. Hence, the changes in the removal and mineralization
of overall organic content, biodegradability, toxicity to Vibrio fischeri, dechlorination of DCF and
its formed by-products, were monitored during the treatment. The obtained data were correlated with
the evolution of DCF by-products, identified and monitored during the treatment by HPLC/MSMS
analysis. In order to estimate the influence of water matrix, all experiments were performed in the
presence of chloride or sulphate as counter ions. The obtained data revealed that degradation
mechanism of DCF by applied treatment process using immobilized TiO2-FeZ includes the adsorption
onto photocatalyst surface and consequent degradation. The contribution of homogeneous Fenton
reaction due to leached iron ions was found to be negligible. The adsorption and degradation pathway of DCF were influenced by the type of counter ions, which was reflected in the observed changes of
water quality parameters.
Found in: osebi
Keywords: Solar photocatalysis, TiO2-FeZ catalyst, Diclofenac, Degradation pathway, Biodegradability, Toxicity
Published: 21.07.2016; Views: 4554; Downloads: 0
 Fulltext (2,10 MB) |
2. Comparative analysis of UV-C/H2O2 and UV-A/TiO2 processes for the degradation of diclofenac in waterUrška Lavrenčič Štangar, Hrvoje Kušić, Marin Kovacic, Daria Juretic Perisic, Vedrana Marin, Ana Lončarić Božić, 2016, original scientific article Abstract: The study investigates the treatment of diclofenac (DCF), a pharmaceutical
included in the first watch list of the European Water Framework Directive
as a new potential priority substance in water. Since the conventional wastewater
treatment technologies do not efficiently remove DCF, advanced treatment technologies
capable of its complete removal or destruction of its biological activity,
need to be evaluated and eventually employed. For that purpose, typical representatives
of photooxidative and photocatalytic advanced oxidation processes were
applied. The effectiveness of UV-C/H2O2 and UV-A/TiO2 were compared regarding
DCF conversion and mineralization kinetics, water quality parameters for
assessing biodegradability and toxicity. In spite of similar biodegradability profiles,
the obtained results indicate different DCF degradation pathways, which are
reflected in different profiles of toxicity towards Vibrio fischeri. The observed DCF
conversion and mineralization kinetics revealed the benefits of UV-C/H2O2 process.
However, lower toxicity favored the application of photocatalytic over photooxidative
treatment for DCF removal.
Found in: osebi
Keywords: Diclofenac, Photooxidation, Photocatalysis, Biodegradability, Toxicity
Published: 21.07.2016; Views: 4096; Downloads: 0
Fulltext (496,03 KB) |
3. Solar-driven photocatalytic treatment of diclofenac using immobilized TiO2-based zeolite compositesUrška Lavrenčič Štangar, Mattia Fanetti, Marko Kete, Andraz Suligoj, Hrvoje Kušić, Subhan Salaeh, Marin Kovacic, Dionysios D. Dionysiou, Ana Lončarić Božić, 2016, original scientific article Abstract: The study is aimed at evaluating the potential of
immobilized TiO2-based zeolite composite for solar-driven
photocatalytic water treatment. In that purpose, TiO2-iron-exchanged
zeolite (FeZ) composite was prepared using commercial
Aeroxide TiO2 P25 and iron-exchanged zeolite of ZSM5
type, FeZ. The activity of TiO2-FeZ, immobilized on glass
support, was evaluated under solar irradiation for removal of
diclofenac (DCF) in water. TiO2-FeZ immobilized in a form
of thin film was characterized for its morphology, structure,
and composition using scanning electron microscopy/energydispersive
x-ray spectroscopy (SEM/EDX). Diffuse reflectance
spectroscopy (DRS) was used to determine potential
changes in band gaps of prepared TiO2-FeZ in comparison
to pure TiO2. The influence of pH, concentration of hydrogen
peroxide, FeZ wt% within the composite, and photocatalyst
dosage on DCF removal and conversion efficiency by solar/
TiO2-FeZ/H2O2 process was investigated. TiO2-FeZ demonstrated
higher photocatalytic activity than pure TiO2 under
solar irradiation in acidic conditions and presence of H2O2.
Found in: osebi
Keywords: Photocatalysis, Thin films, TiO2-FeZ, Solar irradiation, Diclofenac, Water Treatment
Published: 22.07.2016; Views: 5162; Downloads: 0
Fulltext (2,88 MB) |
4. Reuse of TiO2-based catalyst for solar driven water treatment; thermal and chemical reactivationUrška Lavrenčič Štangar, Dominik Kosir, Hrvoje Kušić, Marin Kovacic, Subhan Salaeh, Dionysios D. Dionysiou, Ana Lončarić Božić, 2017, original scientific article Found in: osebi
Keywords: Solar photocatalysis, TiO2-FeZ, Thermal and chemical reactivation, Ozone, Diclofenac
Published: 03.11.2016; Views: 4003; Downloads: 0
Fulltext (3,57 MB) |
5. Photocatalytic sol-gel/P25 TiO [sub] 2 coatings for water treatmentLev Matoh, Boštjan Žener, Marin Kovačić, Hrvoje Kušić, Iztok Arčon, Meta Levstek, Urška Lavrenčič Štangar, 2022, original scientific article Abstract: The effect of different water matrices on the photocatalytic degradation of dissolved pharmaceuticals was
explored. The focus was on the degradation efficiencies in wastewater effluent from a bioreactor and water
effluent from a central wastewater treatment plant and comparing the results with degradation in deionized H2O.
The compounds tested included: oxytetracycline, marbofloxacin, ibuprofen, diclofenac, phenytoin, ciprofloxacin,
sulfamethoxazole. For the experiments performed in this study, a compact packed-bed photocatalytic reactor was
used in which the hybrid TiO2 photocatalyst (sol-gel/P25) was deposited on ~3 mm glass beads. As expected, the
reactions proceed more slowly in wastewater than in deionized water, yet it is shown that removal of the
compounds from the water is still possible even when other organic molecules are present. Total organic carbon
measurements have shown that complete mineralization takes place albeit at slower rates than the initial
degradation of parent compounds. The results show that an acidic pH can increase the reaction rates and the
adsorption on the photocatalyst surface. Analyses of the degradation intermediates were performed using tandem
liquid chromatography triple-quadrupole mass spectrometry system. Additionally, X-ray absorption spectroscopy
was applied to get insight into the local structure of the photocatalyst before and after use. Understanding the
effects that different wastewater compositions have on photocatalytic reactions will help to refine the potential
applications of the technology.
Found in: osebi
Keywords: titanium dioxide, sol-gel processes, functionla applications, water treatment
Published: 30.09.2022; Views: 312; Downloads: 0
Fulltext (8,11 MB) |
