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Abstract(s)
A plantação da folhosa Eucalyptus globulus atinge mundialmente cerca de cerca de 18
milhões de hectares, em 90 países, e destina-se fundamentalmente à produção de pasta
de papel. Promover uma ecovalorização dos resíduos florestais da biomassa de
Eucalytptus globulus, principalmente das cascas e dos ramos, mediante o
desenvolvimento de possíveis aplicações de valor acrescentado, para estes resíduos é o
objetivo principal deste trabalho. Para tal, os resíduos florestais, cascas e ramos de
Eucalyptus globulus que são recursos renováveis, foram convertidos em misturas
líquidas, recorrendo à liquefação, a baixa pressão, com poliálcoois, com vista à síntese
polímeros e de adesivos. Este trabalho teve quatro fases, numa primeira fase foi
realizada a caracterização química desta biomassa residual e foi também, feita a
respetiva, otimização das condições de liquefação; numa segunda fase, caracterizaramse os licores obtidos, e numa terceira fase, produziram-se novos produtos, as espumas
de poliuretano (PU), e os adesivos, a partir da biomassa liquefeita.
Nesta terceira fase interessou avaliar se estes novos produtos podem substituir os seus
congéneres tradicionais originários do petróleo. Assim, relativamente à síntese de
espumas de PU, procedeu-se à otimização da sua produção; avaliaram-se as
propriedades mecânicas das espumas e testaram-se propriedades de espumas obtidas de
licores, de diferentes condições de liquefação. Quanto aos adesivos produzidos
testaram-se as forças de ligação e a resistência ao cisalhamento destes bioadesivos
utilizando o ABES (Automated Bonding Evaluation System) e estimou-se ainda, um
índice semelhante à energia de ativação da reação, de cura da resina feita com ramos de
Eucalyptus globulus liquefeitos. Na última fase do trabalho fez-se análise do ciclo de
vida destes produtos de valor acrescentado obtidos dos resíduos florestais, de casca e
ramos de Eucalyptus globulus com vista a avaliar possíveis impactes ambientais.
ABSTRACT: The hardwood Eucalyptus globulus plantation reaches about 18 million hectares in the world, in 90 countries, and is intended mainly for the production of pulp and paper. Promote a forest biomass waste eco-valorisation of Eucalytptus globulus, mainly of bark and branches, through the development of value-added applications is the main purpose of this work. The forest residues, bark and branches of Eucalyptus globulus which are renewable resources, were converted into liquid mixtures by liquefaction, at low pressure, with polyhydric alcohols to synthesize polymers and adhesives. This work had four phases, the first phase was to held the chemical profile of this biomass and to optimize the liquefaction conditions; in a second phase, the obtained liqueurs were characterised, and in a third phase, new products were produced like polyurethane foams and adhesives, from liquefied biomass. In this third stage it was assessed whether these new products can replace their traditional equivalents from oil. So, for the synthesis of PU foams, the optimization of their production was done; the mechanical properties of the foams were evaluated and liqueurs obtained from different liquefaction conditions were tested. As for the adhesives produced the shear strength of this bio-adhesive was tested using the ABES (Automated Bonding Evaluation System) and it was also estimated an index similar to the activation energy of the resin cure reaction made with liquefied Eucalyptus globulus. In the last phase of the work life cycle analysis of these value added products obtained from forest residues, bark and branches, were obtained to assess potential environmental impacts.
ABSTRACT: The hardwood Eucalyptus globulus plantation reaches about 18 million hectares in the world, in 90 countries, and is intended mainly for the production of pulp and paper. Promote a forest biomass waste eco-valorisation of Eucalytptus globulus, mainly of bark and branches, through the development of value-added applications is the main purpose of this work. The forest residues, bark and branches of Eucalyptus globulus which are renewable resources, were converted into liquid mixtures by liquefaction, at low pressure, with polyhydric alcohols to synthesize polymers and adhesives. This work had four phases, the first phase was to held the chemical profile of this biomass and to optimize the liquefaction conditions; in a second phase, the obtained liqueurs were characterised, and in a third phase, new products were produced like polyurethane foams and adhesives, from liquefied biomass. In this third stage it was assessed whether these new products can replace their traditional equivalents from oil. So, for the synthesis of PU foams, the optimization of their production was done; the mechanical properties of the foams were evaluated and liqueurs obtained from different liquefaction conditions were tested. As for the adhesives produced the shear strength of this bio-adhesive was tested using the ABES (Automated Bonding Evaluation System) and it was also estimated an index similar to the activation energy of the resin cure reaction made with liquefied Eucalyptus globulus. In the last phase of the work life cycle analysis of these value added products obtained from forest residues, bark and branches, were obtained to assess potential environmental impacts.
Description
Keywords
Eucalyptus globulus Liquefação Poliol Espumas de poliuretano Adesivos