Načini sinteze ligninskih modelov

diplomsko delo

Maja Osolnik (Author), Jernej Iskra (Mentor)

Abstract

Lignin je makromolekula, ki se nahaja v celičnih stenah rastlinskih celic. Poleg celuloze in hemiceluloze je lignin glavna sestavina lignocelulozne biomase. Razlogov, zakaj preučevati posamezne ligninske modele namesto lignina kot celote, je več. Lignin ima visoko molekulsko maso, torej je lignin velika biomolekula. Njegovo delovanje in strukturo je lažje razumeti, če najprej razumemo strukturo in delovanje monomernih, dimernih in polimernih ligninskih modelov. Poleg tega se po frakcionaciji biomase na celulozo, hemicelulozo in lignin struktura lignina zaradi kemijskih modifikacij spremeni, in je zaradi tega preučevanje lignina še težje. Nazadnje pa se struktura lignina razlikuje glede na vrsto in starost rastline ter mnogo drugih okoljskih faktorjev. V diplomskem delu je zato shematsko in opisno prikazan pregled nad sintezami najpogostejših struktur, ki jih najdemo znotraj lignina. Metode sintez so povzete iz znanstvene literature. Pregled najprej zajema sinteze monomernih modelov, nato širši pregled sintez dimernih modelov, nazadnje pa je opravljen še kratek pregled nad biomimetično in nebiomimetično sintezo polimernih ligninskih modelov.

Keywords

ligninski modeli;lignocelulozna biomasa;sinteza lignina;diplomska dela;

Data

Language:	Slovenian
Year of publishing:	2022
Typology:	2.11 - Undergraduate Thesis
Organization:	UL FKKT - Faculty of Chemistry and Chemical Technology
Publisher:	[M. Osolnik]
UDC:	547.458.84(043.2)
COBISS:	116105219
Views:	55
Downloads:	24
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Syntheses of model compounds of lignin
Secondary abstract:	Lignin is a macromolecule that is located in plant cell walls. It is the most abundant component of lignocellulosic biomass, right after cellulose and hemicellulose. There are many reasons why it is better to study smaller lignin models instead of lignin as a whole. First, lignin has a high molecular weight, so it is a large biomolecule. Therefore, its structure and functions can be more easily understood if smaller lignin structures are studied first (monomeric, dimeric and polymeric lignin models). Second, it becomes even more difficult to study lignin as a whole when the biomass is fractionated into cellulose, hemicellulose and lignin, because the lignin structure becomes different. Finally, lignin structure as a whole also varies greatly depending on plant species, plant age and many other environmental factors. This diploma thesis contains an overview of the syntheses of the most common lignin models. Most syntheses include reaction schemes and descriptions of experimental work from the scientific literature. Syntheses of monomeric lignin models are described first. Syntheses of dimeric lignin models are overviewed next in a longer part of the thesis. Finally, there is a brief overview of biomimetic and non-biomimetic syntheses of polymeric lignin compounds.
Secondary keywords:	lignin model;lignocellulosic biomass;synthesis of lignin;Lignin;Univerzitetna in visokošolska dela;
Type (COBISS):	Bachelor thesis/paper
Study programme:	1000373
Embargo end date (OpenAIRE):	1970-01-01
Thesis comment:	Univ. v Ljubljani, Fak. za kemijo in kemijsko tehnologijo, UNI Kemija
Pages:	VIII f., 39 str.
ID:	15776732