A new biobleaching sequence for kenaf pulp: influence of the chemical nature of the mediator and thermogravimetric analysis of the pulp
| Autor: | Glòria Andreu, Teresa Vidal, Agustín García Barneto |
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| Rok vydání: | 2012 |
| Předmět: |
Thermogravimetric analysis
Environmental Engineering Bioengineering engineering.material Syringaldehyde chemistry.chemical_compound Bleaching Agents Phenols Lignin Organic chemistry Cellulose Hydrogen peroxide Waste Management and Disposal Laccase biology Renewable Energy Sustainability and the Environment Viscosity Pulp (paper) General Medicine Hydrogen Peroxide biology.organism_classification Kenaf chemistry Hibiscus Thermogravimetry engineering |
| Zdroj: | Bioresource technology. 130 |
| ISSN: | 1873-2976 |
| Popis: | This paper evaluates five phenolic compounds as mediators for kenaf pulp biobleaching by laccase. The results have been compared with the treatment using a non-phenolic mediator, 1-hydroxybenzotriole and laccase alone. The influence of the nature of the chemical mediators used on various pulp properties is discussed. In addition to oxidizing lignin, the phenolic radicals formed in the process take part in condensation and grafting reactions in enzymatic stage. After biobleaching sequence (LP), syringaldehyde was shown to be the best phenolic mediator, allowing a delignification of 43% and 72% ISO brightness. These results were similar to the use of laccase alone due to the role as mediators of syringyl units resulting from oxidative lignin degradation. As a novelty, the study was supplemented with thermogravimetric analysis, with emphasis on the crystallinity degree of the cellulose surface and the aim of elucidating the action mechanisms of laccase-mediator systems on fiber. |
| Databáze: | OpenAIRE |
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