5081. Comparative analysis of UV-C/H2O2 and UV-A/TiO2 processes for the degradation of diclofenac in waterDaria Juretic Perisic, Marin Kovacic, Hrvoje Kušić, Urška Lavrenčič Štangar, Vedrana Marin, Ana Lončarić Božić, 2016, izvirni znanstveni članek Opis: 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.
Ključne besede: Diclofenac, Photooxidation, Photocatalysis, Biodegradability, Toxicity
Objavljeno v RUNG: 21.07.2016; Ogledov: 4928; Prenosov: 0
Gradivo ima več datotek! Več... |
5082. Diclofenac removal by simulated solar assisted photocatalysis using TiO2-based zeolite catalyst; mechanisms, pathways and environmental aspectsSubhan Salaeh, Daria Juretic Perisic, Martina Biosic, Hrvoje Kušić, Sandra Babich, Urška Lavrenčič Štangar, Dionysios D. Dionysiou, Ana Lončarić Božić, 2016, izvirni znanstveni članek Opis: 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.
Ključne besede: Solar photocatalysis, TiO2-FeZ catalyst, Diclofenac, Degradation pathway, Biodegradability, Toxicity
Objavljeno v RUNG: 21.07.2016; Ogledov: 5501; Prenosov: 0
Gradivo ima več datotek! Več... |
5083. Photocatalytic Activity of Zirconium- and Manganese- Codoped Titania in Aqueous Media: The Role of the Metal Dopant and its Incorporation SiteO. L. Pliekhov, Iztok Arčon, Nataša Novak Tušar, Urška Lavrenčič Štangar, 2016, izvirni znanstveni članek Opis: The development of efficient TiO2-based photocatalysts for
water treatment is mainly performed by doping with transition
metals or by establishing junctions between different phases,
metal–semiconductor or semiconductor–semiconductor. We
present, for the first time, the synthesis of Zr- and Mn-modified
TiO2 by a redesigned sol–gel technique that allows the formation
of heterometallic bridges on the TiO2 surface. Cations of
the doping metals are located in the pores of mesoporous
anatase and attached to the crystalline TiO2 walls. The presence
of the Zr enhances the photoactivity of the TiO2 catalyst.
However, the introduction of Mn decreases the photocatalytic
efficiency in a nonadditive manner. The inhibition effect was
assigned to the side reaction between hydroxyl radicals and
Mn ions. The fact that Mn effectively scavenges the hydroxyl
radicals and, consequently, inhibits the whole oxidation process
is direct proof that hydroxyl radicals are the main reactive
species in the photocatalytic oxidative processes on TiO2 surfaces
in aqueous media and the process of COH generation is the
rate-determining step, which was confirmed using a method
based on the decolorization of a commercial dye Bezaktiv Blau
in a reaction with Fenton’s reagent as a source of hydroxyl radicals.
Ključne besede: doping, manganese, oxidation, X-ray absorption spectroscopy, zirconium
Objavljeno v RUNG: 21.07.2016; Ogledov: 4235; Prenosov: 0
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5084. Literatura Damirja Feigla kot zgodovinski, šolski in nacionalni fenomenZoran Božič, 2012, izvirni znanstveni članek Opis: Damir Feigel, primorski pisec humoristične proze, ki je največ ustvarjal v obdobju med dvema vojnama, je s stališča slovenske literarne zgodovine nedvomno obrobni avtor. Podobno je z njegovo prisotnostjo v slovenskih srednješolskih berilih, saj so se odlomki iz Feiglovih leposlovnih besedil pojavili le v zamejskih berilih, in sicer najprej v Budalovem Slovenskem cvetniku leta 1928, po drugi vojni pa še v Čekutovi Slovenski čitanki leta 1947 in v Slovenski čitanki za II. razred Mare Blažina s sodelavci leta 1948. V zadnjih desetletjih se povečuje zanimanje za Feigla kot pisca pustolovske, znanstvenofantastične in humoristične proze. Vsekakor pa je premalo ovrednotena vloga njegove humoristične literature v obdobju fašizma, ko je podobno kot širše znani France Bevk pomagal ohranjati slovensko pisano besedo in s tehniko prikritega sporočila spodbujal nacionalno zavest.
Ključne besede: Damir Feigel, literarna zgodovina, šolska berila, kanonizacija, maskiranje sporočila
Objavljeno v RUNG: 19.07.2016; Ogledov: 4466; Prenosov: 243
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