Kemijsko recikliranje polimernih materijala

undergraduate thesis

• Title (english): Chemical recycling of polymer materials
• Author: Ana Šaravanja
• Mentor: Ljerka Kratofil Krehula (mentor)
• Committee member: Ljerka Kratofil Krehula (predsjednik povjerenstva)
• Committee member: Emi Govorčin Bajsić (član povjerenstva)
• Committee member: Mirela Leskovac (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2021-09-15, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Kemijsko recikliranje polimernih materijala omogućuje potpunu ili djelomičnu depolimerizaciju makromolekulske strukture kako bi se dobili spojevi niske molekulske mase – monomeri, oligomeri ili plinovi. Razmotreno je kemijsko recikliranje poli(etilen-tereftalata) reakcijama glikolize, metanolize i hidrolize (kiselo i bazno katalizirane te neutralne) te kemijsko recikliranje polietilena i polipropilena reakcijom pirolize. Glikolizom PET-a nastaje monomer bis(2-hidroksietil) tereftalat (BHET) zajedno s odgovarajućim oligomerima, metanoliza PET-a rezultira dimetil-tereftalatom (DMT) i etilen-glikolom (EG) kao glavnim produktima dok hidroliza PET-a vodi do tereftalne kiseline (TPA) i etilen-glikola (EG). Pirolizom polietilena (polietilena niske gustoće i polietilena visoke gustoće) i polipropilena događa se cijepanje makromolekula pri čemu nastaju različite plinovite i tekuće frakcije, ovisno o vrsti polimera koji se koriste kao sirovina za recikliranje. Promatran je utjecaj različitih reakcijskih parametara na stupanj depolimerizacije PET-a i razgradnju LDPE-a, HDPE-a i PP-a u spomenutim postupcima kemijskog recikliranja. Vidljivo je da su bolji rezultati postignuti u agresivnijim reakcijskim uvjetima, kao što su viša temperatura, veća količina katalizatora i kemijskih tvari te dulje vrijeme trajanja reakcije.

Abstract (english)

Chemical recycling of polymer materials enables complete or partial depolymerization of the macromolecular structure to generate low molecular weight compounds - monomers, oligomers or gases. Chemical recycling of poly(ethylene-terephthalate) by glycolysis, methanolysis and hydrolysis (acid- and base-catalyzed as well as neutral) and chemical recycling of polyethylene and polypropylene by pyrolysis were analysed. Glycolysis of PET yields the monomer bis(2-hydroxyethyl) terephthalate (BHET) along with its oligomers, methanolysis of PET results in dimethyl terephthalate (DMT) and ethylene glycol (EG) as the main products, while hydrolysis of PET leads to terephthalic acid (TPA) and ethylene glycol (EG). Pyrolysis of polyethylene (low-density polyethylene and high-density polyethylene) and polypropylene causes scission of the macromolecules whereby different gaseous and liquid fractions are obtained, depending on the type of polymer used as raw material for recycling. The effect of various reaction parameters on the depolymerization degree of PET and degradation of LDPE, HDPE and PP in the mentioned chemical recycling processes has been studied. It can be seen that better results were achieved in more aggressive reaction conditions, such as higher temperature, increased quantity of catalyst and chemicals together with longer reaction time.

• Keywords: kemijsko recikliranje; depolimerizacija; otpadni polimerni materijali; zbrinjavanje otpada
• Keywords (english): chemical recycling; depolymerization; waste polymer materials; waste management
• Language: croatian
• URN:NBN: urn:nbn:hr:149:648356
• Study programme: Title: Materials Science and 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: Access restricted to students and staff of home institution
• Created on: 2023-04-24 08:19:55