Modifikacija letećeg pepela kao nosača polimernih fotokatalitičkih nanokompozita

undergraduate thesis

• Title (english): Modification of fly ash for photocatalytic polymer nanocomposites immobilization
• Author: Antonija Tomić
• Mentor: Zlata Hrnjak-Murgić (mentor)
• Committee member: Zlata Hrnjak-Murgić (predsjednik povjerenstva)
• Committee member: Zvonimir Katančić (član povjerenstva)
• Committee member: Nevenka Vrbos (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2015-09-10, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

Leteći pepeo (FA) modificiran je različitim postupcima: klorovodičnom kiselinom
te duljim termičkim tretiranjem kao i sumpornom kiselinom uz prisutnost
tetraetilortosilikata (TEOS) i polietilenglikola (PEG).Tako pripremljenim uzorcima
modificiranog letećeg pepela dodane su nanočestice čistog titanijeva dioksida (TiO2 ) u
iznosu od 10 mas% čime je pripremljena druga serija fotokatalizatora (FA-Ti).
Različitim modifikacijama dolazi do promjene specifične površine i volumena pora
čestica letećeg pepela, stoga su uzorci karakterizirani BET metodom. Zatim im je
karakterizran izgled i struktura čestica letećeg pepela pretražnim elektronskim
mikroskopijom (SEM). Za sve uzorke provedena je ocjena njihove fotokatalitičke
aktivnosti pa je u tu svrhu pripremljena vodena otopina onečišćena bojilom RR45.
Efikasnost fotokatalitičke razgradnje provedena je nakon postupaka adsorpcije bojila na
fotokatalizatore tijekom stajanja u mraku 60 minuta. Fotokatalitička aktivnost određena
je tako da je modelna otopina izložena UV zračenju i svakih 15 minuta, u vremenskom
periodu od 60 minuta, uzimani su alikvoti uzoraka onečišćene vode i određivana im je
apsorbancija na UV/VIS spektrofotometru.
Iz rezultata vidljivo je da uzorci čistog modificiranog letećeg pepela nisu povećali
fotokatalitičku aktivnost pepela, za razliku od kompozitnih uzoraka, modificiranog
letećeg pepela i titanijeva dioksida, gdje je došlo do znatnog unaprijeđenja razgradnje
bojila RR45.

Abstract (english)

Fly ash (FA) has been modified by various methods: by hydrochloric acid with
longer thermal treatment and by sulfuric acid in the presence of tetraethylorthosilicate
(TEOS) and polyethylene glycol (PEG). In thus prepared samples of modified fly ash
nanoparticles of pure titanium dioxide (TiO) in the amount of 10% by weight were
added and new series of photocatalysts (FA-Ti) were prepared. Various modifications
iniciated change of specific surface area and pore volume of the fly ash particles
because of those samples were characterized by BET method. Then, morfology and
structure of the fly ash particles were characteried by scanning electron microscopy
(SEM). For all samples, validation of their photocatalytic activity had been done, and
for this purpose aqueous solution contaminated by dye RR45 was prepared. The
efficiency of photocatalytic activites was carried out after the adsorption procedures of
dyes on photocatalysts during 60 minutes staing in the dark. The photocatalytic activity
is determined in the way that the model solutions was exposed to UV light and every 15
minutes, for a time period of 60 minutes, aliquots samples of contaminated water were
taken and their absorbance is determined by UV / VIS spectrophotometer.
From the results it is evident that modified fly ash samples does not improved
photocatalytic activity of the ash, in contrast to the composite samples, the modified fly
ash and titanium dioxide, which show significant improvement of the photocatalytic
decomposition of dyes RR45.

• Keywords: leteći pepeo; modifikacija; specifična površina; volumen pora; raspodjela veličine čestica; fotokataliza
• Keywords (english): fly ash; modification; specific surface area; pore volume; particle size distribution; photocatalysis
• Language: croatian
• URN:NBN: urn:nbn:hr:149:953902
• Study programme: Title: Chemical Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Repository: Repository of Faculty of Chemical Engineering and Technology University of Zagreb
• Created on: 2016-11-21 13:50:20