Publicação
Bark biorefinery: deconstruction and chemical potential of Eucalyptus globulus and Picea abies barks
| dc.contributor.advisor | Pereira, Helena | |
| dc.contributor.advisor | Gominho, Jorge | |
| dc.contributor.author | Neiva, Duarte Miranda | |
| dc.date.accessioned | 2021-04-06T10:19:12Z | |
| dc.date.available | 2021-04-06T10:19:12Z | |
| dc.date.issued | 2020 | |
| dc.description | Doutoramento em Engenharia Florestal e dos Recursos Naturais / Instituto Superior de Agronomia. Universidade de Lisboa | pt_PT |
| dc.description.abstract | Eucalyptus globulus and Picea abies barks are huge industrial residues with upgradable potential. This research thesis aims at further the knowledge on these barks envisaging production of biomaterials, building blocks, chemicals and fuels. Both industrial barks contained high wood and mineral extraneous contaminants, presenting higher extractives (10-20%) and ash (4-5%), but lower polysaccharides (52-61%) than their respective woods. E. globulus bark hemicelluloses (glucuronoxylan) and lignin (S/G=2.8, enriched in β-O-4’, 83% of all inter-unit linkages elucidated by 2D HSQC-NMR) were similar to those of wood, while P. abies bark differed substantially in hemicelluloses (pectin, higher arabinan, lower mannan) and lignin (γ-OH significant acetylation, presence of hydroxystilbenes glucosides as “nonconventional” true lignin monomers, adding to the canonical established monolignols precursors). The presence of glucosides in lignin was reported for the first time with positive ramifications regarding possible design and bioengineering of polymers with special attributes (hydrophilicity, bioactivity) Deconstruction pathways were tested considering the knowledge gathered. Bleached kraft pulp was produced from E. globulus bark due to previously determined appropriate physical and chemical characteristics. Hydrothermal pre-treatment tested decreased extractives content allowing for lower active alkali (15%) usage in pulping process (resulting in 40% yield) with subsequent bleached pulp and respective handsheets showing similar characteristics to those produced with E. globulus wood. Bark proved to be a possible fiber source feedstock for pulp and paper production. Crude extracts recovered with different solvents were analyzed for neutral monosaccharides and phenolic composition, antioxidant activity, antimicrobial and quorum-sensing potential. Polar extracts showed good or very good antioxidant activity. Gram positive and Candida strains had their growth highly impaired when exposed to n-hexane and ethanol extracts concentrations above 0.04 mg/mL. Extractive-free barks were autohydrolysed and the solid residues saccharified with commercial enzymes (Saczyme and Ultimase), resulting in xylooligosaccharides/arabinooligosaccharides enriched liquors from autohydrolysis, glucose rich streams from enzymatic saccharification and lignin enriched solid residues. This thesis evidences that these abundant industrial residues are interesting materials to be upgraded within a biorefinery concept of full biomass utilization with potential to generate several products and streams with different end-uses | pt_PT |
| dc.description.version | N/A | pt_PT |
| dc.identifier.citation | Neiva, D.M. - Bark biorefinery: deconstruction and chemical potential of Eucalyptus globulus and Picea abies barks. Lisboa: ISA, 2020, 196 p. | pt_PT |
| dc.identifier.tid | 101645279 | |
| dc.identifier.uri | http://hdl.handle.net/10400.5/21209 | |
| dc.language.iso | eng | pt_PT |
| dc.publisher | ISA | pt_PT |
| dc.relation | SUSFOR PROGRAM: SUSTAINABLE FORESTS AND PRODUCTS | |
| dc.subject | bark fractionation | pt_PT |
| dc.subject | enzymatic hydrolisis | pt_PT |
| dc.subject | lignin characterization | pt_PT |
| dc.subject | extractives bioactivity | pt_PT |
| dc.subject | Kraft pulp | pt_PT |
| dc.title | Bark biorefinery: deconstruction and chemical potential of Eucalyptus globulus and Picea abies barks | pt_PT |
| dc.type | doctoral thesis | |
| dspace.entity.type | Publication | |
| oaire.awardTitle | SUSFOR PROGRAM: SUSTAINABLE FORESTS AND PRODUCTS | |
| oaire.awardURI | info:eu-repo/grantAgreement/FCT//PD%2FBD%2F52697%2F2014/PT | |
| project.funder.identifier | http://doi.org/10.13039/501100001871 | |
| project.funder.name | Fundação para a Ciência e a Tecnologia | |
| rcaap.rights | openAccess | pt_PT |
| rcaap.type | doctoralThesis | pt_PT |
| relation.isProjectOfPublication | 6f2d1754-d448-44cc-a85b-1deb32fc40f7 | |
| relation.isProjectOfPublication.latestForDiscovery | 6f2d1754-d448-44cc-a85b-1deb32fc40f7 |