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Avaliação das características dos cepos e raízes de Eucalypto como matéria-prima papeleira

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Resumo:In this study we used stumps and roots of Eucalyptus globulus Labill., from six places, to evaluated its quality as raw-material for papermaking, using two chemical processes: Kraft and ASAM. It was also evaluated the introduction of two pre-treatments: a) extraction with ethanol and water, b) water to promote auto-hydrolysis. It was determined yields of the pulps were the material without pre-treatment presented 42.7% (Kraft) and 49.3% (ASAM); extracted wood 47.5% (Kraft) and 51.7% (ASAM); auto-hydrolyzed material 38.4% (Kraft) and 42.5% (ASAM). It also determined the Kappa number, the degree of polymerization and brightness. Pulps without pre-treatment presented values of (ASAM and Kraft, respectively): 14 K and 36 K, 941 DP0,85 and 929 DP0,85; 25.9% and 23.6% of brightness. For pulps obtained with extracted wood: 11 K and 18 K; 845 DP0,85 and 1004 DP0,85; 30.8% and 35.8% of brightness. For pulps from auto-hydrolyzed materials: 14 K and 20 K; 552 DP0,85 and 574 DP0,85; 27.1% and 28.7% of brightness. There has also been done biometric studies and was obtained the following average results: average length 0.9 mm, a fiber width of 21.4 μm and lumen widths of 9.0 μm. It was determined the index evaluation of paper, based on biometric parameters: number of Runkel (1.4), felting coefficient (43.7) and soupless coefficient (42.5%).
Autores principais:Lopes, Cátia Sofia dos Santos
Assunto:Eucalyptus globulus kraft ASAM auto-hydrolysis extraction roots and stumps
Ano:2012
País:Portugal
Tipo de documento:dissertação de mestrado
Tipo de acesso:acesso aberto
Instituição associada:Universidade de Lisboa
Idioma:português
Origem:Repositório da Universidade de Lisboa
Descrição
Resumo:In this study we used stumps and roots of Eucalyptus globulus Labill., from six places, to evaluated its quality as raw-material for papermaking, using two chemical processes: Kraft and ASAM. It was also evaluated the introduction of two pre-treatments: a) extraction with ethanol and water, b) water to promote auto-hydrolysis. It was determined yields of the pulps were the material without pre-treatment presented 42.7% (Kraft) and 49.3% (ASAM); extracted wood 47.5% (Kraft) and 51.7% (ASAM); auto-hydrolyzed material 38.4% (Kraft) and 42.5% (ASAM). It also determined the Kappa number, the degree of polymerization and brightness. Pulps without pre-treatment presented values of (ASAM and Kraft, respectively): 14 K and 36 K, 941 DP0,85 and 929 DP0,85; 25.9% and 23.6% of brightness. For pulps obtained with extracted wood: 11 K and 18 K; 845 DP0,85 and 1004 DP0,85; 30.8% and 35.8% of brightness. For pulps from auto-hydrolyzed materials: 14 K and 20 K; 552 DP0,85 and 574 DP0,85; 27.1% and 28.7% of brightness. There has also been done biometric studies and was obtained the following average results: average length 0.9 mm, a fiber width of 21.4 μm and lumen widths of 9.0 μm. It was determined the index evaluation of paper, based on biometric parameters: number of Runkel (1.4), felting coefficient (43.7) and soupless coefficient (42.5%).