Sinteza in karakterizacija katalizatorjev za degradacijo polimerov

diplomsko delo visokošolskega strokovnega študijskega programa I. stopnje

Urban Koler (Author), Darja Pečar (Mentor), Andreja Goršek (Co-mentor)

Abstract

Ob zmeraj obsežnejši uporabi plastike in polimerov, kot je polietilen tereftalat, se pojavlja vprašanje rokovanja z odsluženimi produkti. Ponovna predelava odpadne plastike je bila doslej obsežno raziskana, vendar se stopnja predelave polietilen tereftalata gibje le nekje okrog 30 %. Razlog za tako nizko vrednost lahko pripišemo nizkim proizvodnim stroškom nove plastike in visokim stroškom reciklaže, kar občutno dvigne ceno reciklirani plastiki. Kot ena izmed najboljših rešitev pri rokovanju z odpadnim polietilen tereftalatom se pojavljajo kemokatalitični in toplotni pristopi razgradnje na tereftalno kislino in etilen glikol. Najprimernejši katalizatorji za razgradnjo polietilen tereftalata so zeoliti ali silikati, kot na primer ZSM-5 ali SBA-15. SBA-15 je material iz silicijevega dioksida, ki ima veliko specifično površino in je zelo primeren kot nosilec za aktivne komponente - katalizatorje. ZSM-5 je sintetični zeolit, ki vsebuje silicijev dioksid in aluminijev oksid. V tem razmerju prevladuje količina silicijevega dioksida. Katalizator je znan kot ZSM-5, ker ima pore premera 5 Å (angstromov). Tekom študije smo sintetizirali različne kislinske katalizatorje na osnovi SBA-15 z metodo mokre impregnacije in zeolit ZSM-5. Za vezavo na SBA-15 smo kot aktivne soli uporabili: NiNO3, Al(NO3)3, Mg(NO3)2, ZnO, MgO in ZnCl2. Sintetizirane katalizatorje smo okarakterizirali z N2 adsorpcijo, vrstično elektronsko mikroskopijo, temperaturno programirano desorpcijo NH3, diferenčno dinamično kalorimetrijo, termogravimetrično analizo, dinamičnim sipanjem svetlobe in infrardečo spektroskopijo s Fourierjevo transformacijo. Na podlagi karakterizacije smo določili aktivne katalizatorje. Učinkovitost le-teh smo preverjali pri reakciji razgradnje polietilen tereftalata pri povišanih temperaturah. Reakcije razgradnje smo izvedli v visokotlačnih lončkih z uporabo diferenčne dinamične kalorimetrije. Vzorce smo analizirali s tekočinsko kromatografijo visoke ločljivosti sklopljeno z UV-VIS detektorjem.

Keywords

ZSM-5;SBA-15;katalizator;razgradnja;polietilen tereftalat;diplomske naloge;

Data

Language:	Slovenian
Year of publishing:	2023
Typology:	2.11 - Undergraduate Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[U. Koler]
UDC:	66.092.097.3:678.742.2(043.2)
COBISS:	171961091
Views:	46
Downloads:	9
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Synthesis and characterization of catalysts for polymer degradation
Secondary abstract:	With the increasing use of plastics and polymers such as polyethylene terephthalate, the question arises of how to handle end-of-life products. Recycling of waste plastic has been extensively studied, but the recycling rate of polyethylene terephthalate hovers around 30%. The reason for such a low recycling rate can be attributed to the low production costs of new plastic and, of course, the high costs of recycling itself, significantly increasing the price of recycled plastic. One of the most promising solutions for dealing with waste polyethylene terephthalate involves chemocatalytic and thermal degradation approaches to produce terephthalic acid and ethylene glycol. The most suitable catalysts for polyethylene terephthalate degradation are zeolites or silicates, such as ZSM-5 or SBA-15. SBA-15 is a material made of silicon dioxide, possessing a large specific surface area, making it highly suitable as a carrier for active components - catalysts. ZSM-5 is a synthetic zeolite containing silicon dioxide and aluminum oxide, with a higher amount of silicon dioxide prevailing in the ratio. The catalyst is known as ZSM-5 because it has pores with a diameter of 5 Å (angstroms). During the study, various acidic catalysts based on SBA-15 were synthesized using the wet impregnation method, along with zeolite ZSM-5. Active salts such as NiNO3, Al(NO3)3, Mg(NO3)2, ZnO, MgO, and ZnCl2 were used for binding to SBA-15. The synthesized catalysts were characterized using N2 adsorption, scanning electron microscopy, temperature-programmed desorption of NH3, differential scanning calorimetry, thermogravimetric analysis, dynamic light scattering, and Fourier-transform infrared spectroscopy. Based on the characterization, active catalysts were identified. Their effectiveness was tested in the degradation reaction of polyethylene terephthalate at elevated temperatures. The degradation reactions were performed in high-pressure vessels using differential scanning calorimetry. The samples were analyzed using high-performance liquid chromatography coupled with a UV-VIS detector.
Secondary keywords:	ZSM-5;SBA-15;catalyst;degradation;polyethylene terephthalate;
Type (COBISS):	Bachelor thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	1 spletni vir (1 datoteka PDF (VIII, 27 f.))
ID:	20141090