Primerjalna študija predelave surove celuloze listavcev in iglavcev

diplomsko delo univerzitetnega študijskega programa I. stopnje

Urška Hajdinjak (Author), Andreja Goršek (Mentor), Darja Pečar (Mentor)

Abstract

Osnovni cilj diplomskega dela je bil proučiti najučinkovitejšo predobdelavo celuloze listavcev in iglavcev kot alternativnega materiala za obnovljivo energijo. Za učinkovit potek hidrolize celuloze do glukoze smo določili ustrezne procesne pogoje in primerjali izkoristke reakcij. Celulozo smo predobdelovali na več načinov; z mletjem, toplotno obdelavo, ionskimi tekočinami in fosforno (V) kislino. S predobdelavo smo zmanjšali področja kristaliničnosti, kjer so glukozne molekule med seboj povezane z močnimi vezmi. Encimsko hidrolizo celuloze smo izvajali v reaktorju EasyMax 102 (Mettler Toledo) z encimi celulaze. Encimska hidroliza se največkrat izvaja v blagih procesnih pogojih, zato so bile reakcije učinkovite pri temperaturi 45 ˚C in pri uporabi acetatnega pufra (pH = 5). Reakcije so potekale 24 h, njihova izvedba je bila hitra in preprosta. Produkt reakcij hidrolize je bila glukoza, katere koncentracijo smo določili s spektrofotometrično metodo. Na podlagi dobljenih rezultatov smo primerjali izkoristke reakcije s celulozo listavcev in iglavcev. Najučinkovitejša je bila kislinska predobdelava. Rezultati so pokazali najvišje presnove pri celulozi listavcev, v našem primeru evkaliptusa, saj so njegova celulozna vlakna najkrajša in najtanjša. Vsa uporabljena celulozna vlakna smo pred in po kislinski predobdelavi mikroskopirali ter jih posneli z FTIR spektrofotometrom. Posnetki so potrdili naše ugotovitve glede doseženih presnov posameznih reakcij.

Keywords

celuloza;lesna celuloza;celulozna vlakna;encimska hidroliza;encimi;celulaza;predobdelava celuloze;diplomske naloge;

Data

Language:	Slovenian
Year of publishing:	2015
Typology:	2.11 - Undergraduate Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[U. Hajdinjak]
UDC:	661.728.094.941:577.15(043.2)
COBISS:	19450646
Views:	1378
Downloads:	163
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	COMPARATIVE STUDY OF PROCESSING RAW PULP OF DECIDUOUS AND CONIFEROUS
Secondary abstract:	The basic purpose of the thesis was to study the most effective pre-treatment of cellulose of deciduous and coniferous trees as an alternative material for renewable energy. For an effective process of hydrolysis of cellulose to glucose we specified appropriate process conditions and compared the yields of the reactions. The cellulose was pre-treated in several ways; with grinding, thermal treatment, ionic liquids and phosphoric (V) acid. With the pre-treatment we reduced the areas of crystallinity, where the glucose molecules are interconnected with strong bonds. Enzymatic hydrolysis with cellulase enzymes was carried out in an EasyMax 102 (Mettler Toledo) reactor. Enzymatic hydrolysis is most often carried out in mild process conditions, so we achieved the most effective reactions at the temperature of 45 ˚C and with the use of the acetate buffer (pH = 5). The reactions lasted for 24 hours and their execution was quick and easy. The product of hydrolysis reactions was glucose, the concentration of which was determined by a spectrophotometric method. Based on the acquired results we compared the yields of reactions with the cellulose of deciduous and coniferous trees. The most effective was the acidic pre-treatment. The results have shown the highest levels of conversion in the cellulose of deciduous trees, in our case the eucalyptus tree, because they have the shortest and thinnest cellulose fibres. All the used cellulose fibres were microscoped before and after the acidic pre-treatment and filmed them with a FTIR spectrophotometer. The images have confirmed our findings concerning the achieved conversions of individual reactions.
Secondary keywords:	cellulose fibers;enzymatic hydrolysis;enzymes;cellulase;
URN:	URN:SI:UM:
Type (COBISS):	Bachelor thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	IX, 34 str.
ID:	9057653