Uklanjanje mikroonečišćivala grafenom modificiranim TiO2 fotokatalizatorom pod djelovanjem simuliranog Sunčevog zračenja

undergraduate thesis

• Title (english): Removal of micropollutants with graphene modified TiO2 photocatalyst under simulated solar irradiation
• Author: Iva Zokić
• Mentor: Ana Lončarić Božić (mentor)
• Committee member: Ana Vrsalović Presečki (predsjednik povjerenstva)
• Committee member: Ana Lončarić Božić (član povjerenstva)
• Committee member: Hrvoje Kušić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2019-09-06, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Farmaceutici su biološki aktivni spojevi, koji se najčešće koriste za liječenje ljudi i životinja. Ubrajaju se u skupinu novih onečišćivala i njihovo ispuštanje u okoliš nije u potpunosti regulirano. Diklofenak (DCF) je jedan od najpoznatijih protuupalnih, nesteroidnih lijekova razvijen u SAD-u 1980-ih godina. DCF i njegovi metaboliti se akumuliraju u tkivu vodnih organizama te mogu ući u hranidbeni lanac. Za uklanjanje takvih onečišćivala učinkovitima su se pokazali napredni oksidacijski procesi, gdje se posebno ističe fotokataliza. Titanijev dioksid (TiO2) jedan je od najčešćih poluvodičkih materijala koji se upotrebljavaju za heterogenu fotokazalizu, a da bi postao fotokatalitički aktivan mora se izložiti svjetlosnom zračenju valne duljine manje od 384 nm (UV-A). Pripremom novih kompozitnih fotokatalizatora ostvaruje se pomak njihove fotokatalitičke aktivnosti u vidljivo područje spektra elektromagnetskog zračenja, odnosno fotokatalitičku aktivnost je moguće ostvariti pod utjecajem Sunčevog zračenja. U ovom je radu cilj bio uklanjanje DCF-a iz modelne otpadne vode u šaržnom fotoreaktoru djelovanjem simuliranog Sunčevog zračenja primjenom TiO2-rGO nanokompozitnog fotokatalizatora imobiliziranog na staklenom nosaču. TiO2-rGO nanokompozitni fotokatalizator pripremljen je hidrotermalnom metodom sinteze. Primjenom statističkog planiranja eksperimenata prethodno je razvijen puni faktorski plan te su eksperimenti provedeni pri različitom rasponu pH vrijednosti i masenih udjela rGO u kompozitu. Ispitivanje je pokazalo kako je pH značajan parametar procesa, a najbolja konverzija postignuta je pri pH 4. Osim toga, ispitana je i mogućnost modificirane pripreme fotokatalizatora korištenjem komercijalnih komponenata TiO2-P25 i grafena („sendvič“) kako bi se poboljšao međufazni kontakt i time adsorpcija. Utvrđen je visok stupanja adsorpcije i konverzije primjenom sendviča pri pH 6.

Abstract (english)

Pharmaceuticals are biologically active compounds commonly used to treat humans and animals. They are included in the group of new pollutants and their release into the environment is not fully regulated. Diclofenac (DCF) is one of the most famous anti-inflammatory, non-steroidal drugs developed in the United States in the 1980s. DCF and its metabolites accumulate in the tissue of aquatic organisms and can be incorporated into the food chain. For the removal of such pollutants, advanced oxidation processes have proven effective, with particular emphasis on photocatalysis. Titanium dioxide (TiO2) is one of the most common semiconductor materials used for heterogeneous photocatalysis, and in order to become photocatalytically active it must be exposed to light radiation of a wavelength less than 384 nm (UV-A). The preparation of new composite photocatalysts results in the shift of their photocatalytic activity into the visible region of the electromagnetic radiation spectrum, so they can be activated under the solar irradiation. In this paper, the aim was to remove DCF from the model wastewater in a batch photoreactor by simulated solar radiation using a TiO2-rGO nanocomposite photocatalyst immobilized on a glass support. The TiO2-rGO nanocomposite photocatalyst was prepared by hydrothermal synthesis. A full factorial plan was previously developed using statistical planning of experiments, and experiments were performed at different pH ranges and rGO propotions in the composite. Results showed that pH is a significant parameter of the process and the highest conversion was achieved at pH 4. In addition, the possibility of modified photocatalyst preparation using commercial
TiO2-P25 and graphene („sandwich“) components was tested to improve DCF conversion. The best removal of DCF was determined with commercial TiO2-P25 at pH 4 and TiO2-P25 graphene „sandwiches“ at pH 6.

• Keywords: farmaceutici; diklofenak; heterogena fotokataliza; nanokompozitni fotokatalizator TiO2-rGO
• Keywords (english): famaceuticals; diclofenac; heterogeneous photocatalysis; TiO2-rGO nano-composite photocatalyst
• Language: croatian
• URN:NBN: urn:nbn:hr:149:865709
• Project: Number: IP-2018-01-1982; Title: Nano-katalizatori aktivirani Sunčevim zračenjem u tehnologijama zaštite okoliša; Title: Nano-sized solar-active catalysts for environmental technologies; Acronym: NaSCEnT; Leader: Hrvoje Kušić; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Study programme: Title: Environmental Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka ekoinženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka ekoinženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2023-05-29 12:48:12