Efeito da hidrólise ácida em propriedades de nanocelulose vegetal
Autor(a) principal: | |
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Data de Publicação: | 2022 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Manancial - Repositório Digital da UFSM |
Texto Completo: | http://repositorio.ufsm.br/handle/1/30325 |
Resumo: | Cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC) are two types of nanocellulose that have morphological, structural and surface characteristics that allow them to be applied in the industrial and biomedical sectors for the development of green products with high added value and low environmental impact, and can be extracted from abundant and renewable resources such as agro-industrial waste and forestry resources. CNCs are extracted from plant cellulose, usually by mechanical or chemical methods or a combination of these to obtain CNCs with a diameter of less than 100 nm and a length of several micrometers. CNCs are isolated from the acid hydrolysis of cellulose fibers using concentrated mineral acid. Sulphuric acid is the most commonly used acid hydrolysis acid because it preferentially breaks the cellulose chains from the amorphous regions of the cellulose chains, releasing CNCs with high crystallinity and colloidal stability in aqueous media. The general aim of this study was to obtain nanocellulose from vegetable cellulose sources and to check the effect of hydrolysis parameters on the yield and properties of nanocellulose. In Article 1, delignified kraft pulp from Acacia mearsii wood was hydrolyzed with different concentrations of sulfuric acid in order to verify the effect of acid concentration on the yield and properties of cellulose nanocrystals. Article 2 aimed to individualize cellulose nanofibrils from açaí waste by applying acid hydrolysis using sulphuric acid with different hydrolysis times as a pre-treatment for nanofibrillation in an ultrasonic probe processor. The results obtained in this study showed that it is possible to obtain high yields and nanocellulose with high crystallinity, stability in aqueous media, and high thermal stability by using the acid hydrolysis method to obtain CNC from the delignified kraft cellulosic pulp of Acacia mearnsii in Article 1. And applying acid hydrolysis as a pre-treatment for ultrasonic nanofibrillation to obtain cellulose nanofibrils from delignified açaí residue in Article 2. In both articles, it was found that varying the hydrolysis parameters was responsible for changes in the yield and morphological, thermal and structural properties of the nanocellulose. |
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Efeito da hidrólise ácida em propriedades de nanocelulose vegetalEffect of acid hydrolysis conditions on plant nanocellulose propertiesNanocristais de celuloseNanofibrilas de celuloseÁcido sulfúricoAcacia mearsiiEuterpe oleraceaCellulose nanocrystalsCellulose nanofibrilsSulphuric acidCNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTALCellulose nanofibrils (CNF) and cellulose nanocrystals (CNC) are two types of nanocellulose that have morphological, structural and surface characteristics that allow them to be applied in the industrial and biomedical sectors for the development of green products with high added value and low environmental impact, and can be extracted from abundant and renewable resources such as agro-industrial waste and forestry resources. CNCs are extracted from plant cellulose, usually by mechanical or chemical methods or a combination of these to obtain CNCs with a diameter of less than 100 nm and a length of several micrometers. CNCs are isolated from the acid hydrolysis of cellulose fibers using concentrated mineral acid. Sulphuric acid is the most commonly used acid hydrolysis acid because it preferentially breaks the cellulose chains from the amorphous regions of the cellulose chains, releasing CNCs with high crystallinity and colloidal stability in aqueous media. The general aim of this study was to obtain nanocellulose from vegetable cellulose sources and to check the effect of hydrolysis parameters on the yield and properties of nanocellulose. In Article 1, delignified kraft pulp from Acacia mearsii wood was hydrolyzed with different concentrations of sulfuric acid in order to verify the effect of acid concentration on the yield and properties of cellulose nanocrystals. Article 2 aimed to individualize cellulose nanofibrils from açaí waste by applying acid hydrolysis using sulphuric acid with different hydrolysis times as a pre-treatment for nanofibrillation in an ultrasonic probe processor. The results obtained in this study showed that it is possible to obtain high yields and nanocellulose with high crystallinity, stability in aqueous media, and high thermal stability by using the acid hydrolysis method to obtain CNC from the delignified kraft cellulosic pulp of Acacia mearnsii in Article 1. And applying acid hydrolysis as a pre-treatment for ultrasonic nanofibrillation to obtain cellulose nanofibrils from delignified açaí residue in Article 2. In both articles, it was found that varying the hydrolysis parameters was responsible for changes in the yield and morphological, thermal and structural properties of the nanocellulose.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESNanofibrilas de celulose (CNF) e nanocristais de celulose (CNC), são dois tipos de nanocelulose, que apresentam características morfológicas, estruturais e de superfície que permitem a aplicação em setores industriais e biomédicos para o desenvolvimento de produtos verdes, com alto valor agregado, baixo impacto ambiental, e podem ser extraídas de fontes recursos abundantes e renováveis como resíduos agroindustriais e recursos florestais. As CNFs são extraídas de celulose vegetal, geralmente por métodos mecânicos, químicos ou a combinação de destes para obter CNFs com diâmetro menor que 100 nm, e comprimento de vários micrometros. Os CNCs são isolados a partir da hidrólise ácida das fibras de celulose usando ácido mineral concentrado. O ácido sulfúrico é o mais empregado para realizar a hidrólise ácida, por quebrar preferencialmente as cadeias de celulose das regiões amorfas das cadeias de celulose, liberando CNC com elevada cristalinidade, e estabilidade coloidal em meio aquoso. O presente estudo teve como objetivo geral, obter nanocelulose de fontes de celulose vegetal, e verificar o efeito dos parâmetros de hidrólise no rendimento e propriedades das nanoceluloses, e está estruturado em 2 artigos. No Artigo 1, a polpa kraft deslignificada de madeira de Acacia mearsii foi hidrolisada com diferentes concentrações de ácido sulfúrico com o objetivo de verificar o efeito da concentração ácida no rendimento e propriedades dos nanocristais de celulose. O Artigo 2 teve como objetivo, individualizar nanofibrilas de celulose do resíduo de açaí aplicando a hidrólise ácida por ácido sulfúrico com diferentes tempos de hidrólise como pré-tratamento da nanofibrilação em processador ultrassônico de sonda. Os resultados obtidos neste estudo demonstraram que é possível obter elevados rendimentos e nanoceluloses com elevada cristalinidade, estabilidade em meio aquoso, e alta estabilidade térmica empregando o método de hidrólise ácida para obter CNC da polpa celulósica kraft deslignificada de Acacia mearnsii no Artigo 1. E aplicando a hidrólise ácida como prétratamento para nanofibrilação ultrassônica para obter nanofibrilas de celulose do resíduo de açaí deslignificado no Artigo 2. Nos dois artigos verificou-se que a variação dos parâmetros de hidrólise foi responsável por alterações no rendimento e propriedades morfológicas, térmicas e estruturais das nanoceluloses.Universidade Federal de Santa MariaBrasilRecursos Florestais e Engenharia FlorestalUFSMPrograma de Pós-Graduação em Engenharia FlorestalCentro de Ciências RuraisPedrazzi, Cristianehttp://lattes.cnpq.br/5167571704789298Gatto, Darci AlbertoGomes, Claudia MarciaDelucis, Rafael de AvilaFarias, Daniel Tavares de2023-10-09T19:28:09Z2023-10-09T19:28:09Z2022-09-30info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://repositorio.ufsm.br/handle/1/30325porAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccessreponame:Manancial - Repositório Digital da UFSMinstname:Universidade Federal de Santa Maria (UFSM)instacron:UFSM2023-10-09T19:28:09Zoai:repositorio.ufsm.br:1/30325Biblioteca Digital de Teses e Dissertaçõeshttps://repositorio.ufsm.br/ONGhttps://repositorio.ufsm.br/oai/requestatendimento.sib@ufsm.br||tedebc@gmail.comopendoar:2023-10-09T19:28:09Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM)false |
dc.title.none.fl_str_mv |
Efeito da hidrólise ácida em propriedades de nanocelulose vegetal Effect of acid hydrolysis conditions on plant nanocellulose properties |
title |
Efeito da hidrólise ácida em propriedades de nanocelulose vegetal |
spellingShingle |
Efeito da hidrólise ácida em propriedades de nanocelulose vegetal Farias, Daniel Tavares de Nanocristais de celulose Nanofibrilas de celulose Ácido sulfúrico Acacia mearsii Euterpe oleracea Cellulose nanocrystals Cellulose nanofibrils Sulphuric acid CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL |
title_short |
Efeito da hidrólise ácida em propriedades de nanocelulose vegetal |
title_full |
Efeito da hidrólise ácida em propriedades de nanocelulose vegetal |
title_fullStr |
Efeito da hidrólise ácida em propriedades de nanocelulose vegetal |
title_full_unstemmed |
Efeito da hidrólise ácida em propriedades de nanocelulose vegetal |
title_sort |
Efeito da hidrólise ácida em propriedades de nanocelulose vegetal |
author |
Farias, Daniel Tavares de |
author_facet |
Farias, Daniel Tavares de |
author_role |
author |
dc.contributor.none.fl_str_mv |
Pedrazzi, Cristiane http://lattes.cnpq.br/5167571704789298 Gatto, Darci Alberto Gomes, Claudia Marcia Delucis, Rafael de Avila |
dc.contributor.author.fl_str_mv |
Farias, Daniel Tavares de |
dc.subject.por.fl_str_mv |
Nanocristais de celulose Nanofibrilas de celulose Ácido sulfúrico Acacia mearsii Euterpe oleracea Cellulose nanocrystals Cellulose nanofibrils Sulphuric acid CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL |
topic |
Nanocristais de celulose Nanofibrilas de celulose Ácido sulfúrico Acacia mearsii Euterpe oleracea Cellulose nanocrystals Cellulose nanofibrils Sulphuric acid CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL |
description |
Cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC) are two types of nanocellulose that have morphological, structural and surface characteristics that allow them to be applied in the industrial and biomedical sectors for the development of green products with high added value and low environmental impact, and can be extracted from abundant and renewable resources such as agro-industrial waste and forestry resources. CNCs are extracted from plant cellulose, usually by mechanical or chemical methods or a combination of these to obtain CNCs with a diameter of less than 100 nm and a length of several micrometers. CNCs are isolated from the acid hydrolysis of cellulose fibers using concentrated mineral acid. Sulphuric acid is the most commonly used acid hydrolysis acid because it preferentially breaks the cellulose chains from the amorphous regions of the cellulose chains, releasing CNCs with high crystallinity and colloidal stability in aqueous media. The general aim of this study was to obtain nanocellulose from vegetable cellulose sources and to check the effect of hydrolysis parameters on the yield and properties of nanocellulose. In Article 1, delignified kraft pulp from Acacia mearsii wood was hydrolyzed with different concentrations of sulfuric acid in order to verify the effect of acid concentration on the yield and properties of cellulose nanocrystals. Article 2 aimed to individualize cellulose nanofibrils from açaí waste by applying acid hydrolysis using sulphuric acid with different hydrolysis times as a pre-treatment for nanofibrillation in an ultrasonic probe processor. The results obtained in this study showed that it is possible to obtain high yields and nanocellulose with high crystallinity, stability in aqueous media, and high thermal stability by using the acid hydrolysis method to obtain CNC from the delignified kraft cellulosic pulp of Acacia mearnsii in Article 1. And applying acid hydrolysis as a pre-treatment for ultrasonic nanofibrillation to obtain cellulose nanofibrils from delignified açaí residue in Article 2. In both articles, it was found that varying the hydrolysis parameters was responsible for changes in the yield and morphological, thermal and structural properties of the nanocellulose. |
publishDate |
2022 |
dc.date.none.fl_str_mv |
2022-09-30 2023-10-09T19:28:09Z 2023-10-09T19:28:09Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://repositorio.ufsm.br/handle/1/30325 |
url |
http://repositorio.ufsm.br/handle/1/30325 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Recursos Florestais e Engenharia Florestal UFSM Programa de Pós-Graduação em Engenharia Florestal Centro de Ciências Rurais |
publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Recursos Florestais e Engenharia Florestal UFSM Programa de Pós-Graduação em Engenharia Florestal Centro de Ciências Rurais |
dc.source.none.fl_str_mv |
reponame:Manancial - Repositório Digital da UFSM instname:Universidade Federal de Santa Maria (UFSM) instacron:UFSM |
instname_str |
Universidade Federal de Santa Maria (UFSM) |
instacron_str |
UFSM |
institution |
UFSM |
reponame_str |
Manancial - Repositório Digital da UFSM |
collection |
Manancial - Repositório Digital da UFSM |
repository.name.fl_str_mv |
Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM) |
repository.mail.fl_str_mv |
atendimento.sib@ufsm.br||tedebc@gmail.com |
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1805922125442187264 |