Ocjena fotokatalitičke aktivnosti PEDOT/TiO2 fotokatalizatora tijekom razgradnje Acid Blue 25 bojila u vodi uz simulirano Sunčevo zračenje

master's thesis

• Title (english): Validation of photocatalytic activity of PEDOT/TiO2 photocatalyst during decomposition of Acid Blue 25 dye in water under simulated solar irradiation
• Author: Petra Klarić
• Mentor: Zlata Hrnjak-Murgić (mentor)
• Committee member: Zlata Hrnjak-Murgić (predsjednik povjerenstva)
• Committee member: Zvonimir Katančić (član povjerenstva)
• Committee member: Suzana Sopčić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2017-07-14, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

Pročišćavanje otpadnih voda moguće je na više načina, različitim metodama i procesima: mehaničkim uklanjanjem onečišćenja, fizikalnim, biološkim i kemijskim metodama. Fotokataliza je proces koji se ubraja u kemijske metode pročišćavanja otpadnih voda, a provodi se upotrebom fotokatalizatora od kojih su najčešći metalni oksidi (TiO2, ZnO...). Kako TiO2 ima ograničeno djelovanje pod vidljivom svjetlošću zbog velike širine zabranjene zone, sintetizirani su kemijskom oksidacijskom polimerizacijom, kompozitni fotokatalizatori vodljivog polimera poli(3,4-etilendioksitiofena) (PEDOT) i TiO2 uz oksidans FeCl3. Kompoziti su sadržavali različite omjere PEDOT-a i TiO2. Sintetizirani kompozitni fotokatalizatori su karakterizirani mjerenjem elektrovodljivosti metodom četiri točke te im je ispitana toplinska stabilnost termogravimetrijskom analizom. Njihova fotokatalitička aktivnost ispitana je praćenjem razgradnje Acid Blue 25 (AB25) bojila u vodi uz simulirano Sunčevo zračenje. Tijekom procesa fotokatalize praćeno je obezbojenje određivanjem promjene apsorbancije korištenjem UV/Vis spektrofotometra. Također, praćen je proces mineralizacije AB25 bojila mjerenjem ukupnog organskog ugljika (TOC). Nadalje, provedena je optimizacija uvjeta fotokatalize gdje se ispitivao utjecaj kiselosti/lužnatosti (pH) i utjecaj „scavangera“ (EDTA, metanol i 2-propanol). Rezultati su pokazali da veći udio polimera u kompozitu pokazuje veliku moć adsorpcije molekula boje, a veća fotokatalitička aktivnost postiže se uz mali udio polimera.

Abstract (english)

Wastewater treatment is possible by different methods and processes: mechanical removal of impurities, physical, biological and chemical methods. Photocatalysis is one of the chemical methods of wastewater treatment and is carried out by using a photocatalysts such as metal oxides (TiO2, ZnO...). As TiO2 has limited efficiency under visible light due to large band gap, composite photocatalysts of conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) and TiO2 with oxidant FeCl3 were synthesized by chemical oxidative polymerization. Composites had different PEDOT:TiO2 ratio. Characterization of the photocatalysts was carried out by measuring conductivity with four point probe test and determination of thermal stability by thermogravimetric analysis. The photocatalytic efficiency of the synthesized nanocomposite photocatalysts was examined by monitoring the removal of Acid Blue 25 (AB25) dye under the simulated solar irradiation.during The discoloration was followed by UV/Vis spectrophotometer and as a measure of dye mineralization total organic carbon (TOC) was determined. Optimization of photocatalytic conditions was carried out in terms of examining the impact of acidity/alkalinity (pH) and impact of scavengers (EDTA, methanol and 2-propanol). Results showed that in case of the higher ratio of polymer in composite dye molecules adsorption is high while better photocatalytic effect is achieved at lower polymer amount in composite.

• Keywords: fotokataliza; otpadne vode; napredni oksidacijski procesi; nanokompozit; poli(3 4-etilendioksitiofen); titanijev dioksid
• Keywords (english): photocatalysis; waste water; advanced oxidation processes; nanocomposite; poly(3 4-ethylenedioxythiophene); titanium dioxide
• Language: croatian
• URN:NBN: urn:nbn:hr:149:272441
• Study programme: Title: Materials Science and Engineering - Graduate study; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka kemijskog inženjerstva (magistar/magistra inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-04-21 14:35:43