Utilize este identificador para referenciar este registo:
https://hdl.handle.net/10316/14248
Título: | ECF bleaching with a final hydrogen peroxide stage: Impact of the chemical composition of Eucalyptus globulus kraft pulps | Autor: | Loureiro, Pedro E. G. Domingues, Eva F. Evtuguin, Dmitry V. Carvalho, M. Graça V. S. |
Palavras-chave: | Oxidation; Carboxyl groups; Carbonyl groups; Hexeneuronic acids; Intrinsic viscosity; Bleaching history | Data: | 2010 | Editora: | College of Natural Resources | Citação: | LOUREIRO, Pedro E. G. [et al.] - ECF bleaching with a final hydrogen peroxide stage: Impact of the chemical composition of Eucalyptus globulus kraft pulps. "BioResources". ISSN 1930-2126. 5:4 (2010) 2567-2580 | Título da revista, periódico, livro ou evento: | BioResources | Número: | 4 | Resumo: | Two industrial elemental chlorine free (ECF) bleaching sequences, D0(EOP)D1(EP)D2 and OQ(PO)DP, are compared with respect to the bulk content of lignin, carboxyl, hexeneuronic acids (HexA), and reducing groups after each bleaching stage. HexA groups contribute significantly to the total content of carboxyl groups, and their degradation during chlorine dioxide bleaching is reflected by a decrease of the carboxyl content. The higher degradation using an enhanced use of oxygenbased bleaching chemicals is associated with a higher fiber charge reduction, mainly due to xylan depletion. Additionally, the effect of process variables of a laboratory final hydrogen peroxide stage on the chemical composition of the fully bleached pulp (D0(EOP)D1P and OQ(PO)DP) is studied. The ability of final peroxide bleaching to raise the content of carboxyl groups is dependent on the operating conditions and pulp bleaching history. A balance between carbohydrate oxidation and dissolution of oxidized groups determines the effect on fiber charge. The effect of hydrogen peroxide stabilizers added into the final stage on the content of carboxyl groups is also reported. | URI: | https://hdl.handle.net/10316/14248 | ISSN: | 1930-2126 | Direitos: | openAccess |
Aparece nas coleções: | FCTUC Eng.Química - Artigos em Revistas Internacionais |
Ficheiros deste registo:
Ficheiro | Descrição | Tamanho | Formato | |
---|---|---|---|---|
ECF bleaching with a final hydrogen peroxide stage.pdf | 179.43 kB | Adobe PDF | Ver/Abrir |
Visualizações de página 50
480
Visto em 1/out/2024
Downloads
150
Visto em 1/out/2024
Google ScholarTM
Verificar
Todos os registos no repositório estão protegidos por leis de copyright, com todos os direitos reservados.