Title Fotokatalitička razgradnja torasemida s imobiliziranim TiO2 Title (english) Photocatalytic decomposition of torasemide with imobilised TiO2 Author Minea Pranjić Mentor Dragana Mutavdžić Pavlović (mentor)Committee member Dragana Mutavdžić Pavlović (predsjednik povjerenstva)Committee member Kristina Tolić Čop (član povjerenstva)Committee member Lidija Furač (član povjerenstva)Granter University of Zagreb Defense date and country 2023-09-21, Croatia Scientific / art field, NATURAL SCIENCES Abstract Posljednjih nekoliko desetljeća farmaceutski aktivni spojevi smatrani su zagađivalima u nastajanju zbog njihovog kontinuiranog otpuštanja i postojanosti u vodenom okolišu čak i pri niskim koncentracijama. No sve veći broj istraživačkih članaka potvrđuje njihovu prisutnost analiziranjem različitih dotoka iz postrojenja za pročišćavanje otpadnih voda, bolničkih otpadnih voda i površinskih voda diljem svijeta. Rastuća zabrinutost u vezi s farmaceuticima, koji pokazuju veliki otpor prema konvencionalnim metodama uklanjanja, potaknula je opsežna istraživanja na području njihove učinkovite sanacije. Ovaj istraživački rad pruža procjenu heterogenog fotokatalitičkog procesa za uklanjanje farmaceutika torasemida kao potencijalne metode za primjenu prilikom pročišćavanja zagađenih vodenih sustava, uz primjenu fotokatalizatora na bazi TiO2. Kako bi potvrdili prikladnost analitičke metode za određivanje torasemida u vodi provedena je njena validacija koja se sveukupno pokazala zadovoljavajućom. Provedeni su i preliminarni eksperimenti hidrolize, adsorpcije i fotolize koji nemaju značajan utjecaj na razgradnju te se oslanjamo isključivo na fotokatalizu. Nakon toga ispitani su utjecaji pH vrijednosti i početne koncentracije farmaceutika pri čemu su određeni i optimalni uvjeti za razgradnju, a to su pH 4 i 5 mg/L. Provedeno je ispitivanje utjecaja „hvatača“ reaktivnih čestica pri čemu se pokazalo kako •OH radikali imaju najveću ulogu u razgradnji. Prilikom promatranja razgradnje smjese farmaceutika, imatiniba i torasemida, zaključilo se kako se povećanjem koncentracije smjese smanjuje brzina razgradnje što je posljedica zasićenosti površine fotokatalizatora. Razni ioni prisutni u matici vode također pokazuju velik utjecaj na fotokatalizu farmaceutika od kojih kompleksne huminske kiseline najviše usporavaju razgradnju. U konačnici primjenom realne otpadne vode fotokatalitički proces se najviše usporio zbog prisutnosti raznih onečišćenja. Analizom otopine torasemida nakon fotokatalitičke razgradnje pri optimalnim uvjetima utvrđeno je 7 različitih transformacijskih produkata koji su potencijalno štetniji od primarnog farmaceutika i tijekom eksperimenta moguće usporili razgradnju torasemida natjecanjem za vezno mjesto na fotokatalizatoru.
Abstract (english) In recent decades, pharmaceutical agents have been considered as emerging pollutants due to their continuous release and persistence in the aquatic environment, even at low concentrations. However, a growing number of research articles confirm their presence through the analysis of various influents from wastewater treatment plants, hospital effluents, and surface waters worldwide. Increasing concern about pharmaceuticals that exhibit significant resistance to conventional removal methods has led to extensive research in the area of their effective remediation. This research provides an evaluation of the heterogeneous photocatalytic process for the removal of the pharmaceutical torasemide as a potential method for application in the cleanup of polluted water systems using a TiO2-based photocatalyst. To verify the suitability of the method, its validation was carried out, which proved to be satisfactory overall. Preliminary experiments on hydrolysis, adsorption and photolysis were performed, which showed no significant effect on degradation, thus relying solely on photocatalysis. Subsequently, the influences of pH and initial pharmaceutical concentration were investigated, and optimal degradation conditions were determined to be pH 4 and 5 mg/L. An investigation of the effects of scavengers of reactive particles revealed that •OH radicals played the most important role in degradation. Observing the degradation of a pharmaceutical mixture, imatinib and torasemide, it was found that increasing the mixture concentration decreased the degradation rate due to saturation of the catalyst surface. Various ions present in the water matrix also exert a significant influence on pharmaceutical photocatalysis, with complex humic acids inhibiting degradation the most. Finally, when real wastewater was used, the photocatalytic process was significantly slowed down by the presence of various impurities. Analysis of the torasemide solution after photocatalytic degradation under optimal conditions revealed seven different transformation products that are potentially more harmful than the primary pharmaceutical compound and further hinder torasemide degradation as they compete for binding sites on the photocatalyst.
Keywords
zagađivala
vodeni okoliš
napredni oksidacijski procesi
heterogena fotokataliza
TiO2
torasemid
radikali
Keywords (english)
pollutants
aquatic environment
advanced oxidation processes
heterogeneous photocatalysis
TiO2
torasemide
radicals
Language croatian URN:NBN urn:nbn:hr:149:957100 Study programme Title: Applied Chemistry - Graduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry Type of resource Text File origin Born digital Access conditions Embargoed access Terms of use Created on 2023-11-20 13:11:10
