Pattern of Alkali Impregnation of Poplar Wood at Moderate Conditions
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M. Zanuttini
Summary
The impregnation pattern of alkali in fresh Cottonwood is analysed. Isothermal process, medium alkali-concentration, temperature below 100°C and tangential direction are considered. The degree of deacetylation in the wood is taken as an indicator of the whole chemical action of the alkali. Profiles of alkali concentration, alkali content, liquid content and acetyl content in the wood are experimentally determined. The results show that wood behaves rather like a glassy polymeric solid placed in contact with a solvent. An advancing boundary zone is established which separates an intact inner part from the outer swollen zone. Alkali concentration and acetyl groups content profiles can approximately be described by a model used to analyse the reaction of solids: the shrinking core model. The chemical reaction in the front is the controlling mechanism. The swelling of the cell walls together with the occupation of the hollow cavities of the wood by the liquor make it possible for the wood liquid content to increase up to almost 3 g liquid g wood−1.
The procedure here adopted and the impregnation pattern proposed are valuable tools to analyse the effect of wood direction and process variables such as temperature, alkali concentration and initial wood moisture. They could also be very useful to build a model for alkaline impregnation of wood under moderate conditions.
Copyright © 2000 by Walter de Gruyter GmbH & Co. KG
Articles in the same Issue
- Species Index
- Author Index
- Contents
- Subject Index
- Yeast and Bacteria as Biological Control Agents Against Fungal Discolouration of Pinus sylvestris Blocks in Laboratory-Based Tests and the Role of Antifungal Volatiles
- Copper Accumulation in the Digestive Caecae of Limnoria quadripunctata Holthius (Isopoda: Crustacea) Tunnelling CCA-Treated Wood in Laboratory Cultures
- Chromated Copper Arsenate Preservative Treatment of North American Hardwoods. Part 1. CCA Fixation Performance
- Medium Density Fibreboard Manufactured from Blends of White Cypress Pine and Non-Durable Wood Species Shows Increased Resistance to Attack by the Subterranean Termite C. lacteus
- Role of a Labile Terpene Compound in the Assessment of the Age of a Fossil Wood from Siena (Tuscany, Italy)
- Neolignan Skeletons and Benzodioxanes Through Chiral Aryl Alkyl Ether Formation
- Use of β-13 C labelled Coniferyl Alcohol to Detect "End-Wise" Polymerization in the Formation of DHPs
- Bleachability of Alkaline Pulps. Part 1. The Importance of β-Aryl Ether Linkages in Lignin
- Solid State NMR Studies on Cellulose Crystallinity in Fines and Bulk Fibres Separated from Refined Kraft Pulp
- Pulping of Whole Jute Plant (Corchorus capsularies) by Soda-Amine Liquor
- Pattern of Alkali Impregnation of Poplar Wood at Moderate Conditions
- Structure and Reactivity of Lignins and Associated Phenolic Acids in Wheat Straw TMP and CTMP Pulps
- Thermal Reactions of N-Methyl-morpholine-N-oxide (NMMO): A General Method for Separation and Quantification of N-Methyl-morpholine-N-oxide and its Main Degradation Products N-Methylmorpholine and Morpholine by Capillary Electrophoresis (CE)
- The Kismet of Residual During LMS Delignification of High-Kappa Kraft Pulps
- Variations in Transverse Fibre Wall Properties: Relations Between Elastic Properties and Structure
- Application of the GAB Sorption Isotherm Model to Klinki Pine (Araucaria klinkii Lauterb.)
- Strain Changes on the Inner Bark Surface of an Inclined Coniferous Sapling Producing Compression Wood
- Effects of Chemical Modification Reagents on Acoustic Properties of Wood
- J.L. McCarthy In Memoriam
- Acknowledgement
Articles in the same Issue
- Species Index
- Author Index
- Contents
- Subject Index
- Yeast and Bacteria as Biological Control Agents Against Fungal Discolouration of Pinus sylvestris Blocks in Laboratory-Based Tests and the Role of Antifungal Volatiles
- Copper Accumulation in the Digestive Caecae of Limnoria quadripunctata Holthius (Isopoda: Crustacea) Tunnelling CCA-Treated Wood in Laboratory Cultures
- Chromated Copper Arsenate Preservative Treatment of North American Hardwoods. Part 1. CCA Fixation Performance
- Medium Density Fibreboard Manufactured from Blends of White Cypress Pine and Non-Durable Wood Species Shows Increased Resistance to Attack by the Subterranean Termite C. lacteus
- Role of a Labile Terpene Compound in the Assessment of the Age of a Fossil Wood from Siena (Tuscany, Italy)
- Neolignan Skeletons and Benzodioxanes Through Chiral Aryl Alkyl Ether Formation
- Use of β-13 C labelled Coniferyl Alcohol to Detect "End-Wise" Polymerization in the Formation of DHPs
- Bleachability of Alkaline Pulps. Part 1. The Importance of β-Aryl Ether Linkages in Lignin
- Solid State NMR Studies on Cellulose Crystallinity in Fines and Bulk Fibres Separated from Refined Kraft Pulp
- Pulping of Whole Jute Plant (Corchorus capsularies) by Soda-Amine Liquor
- Pattern of Alkali Impregnation of Poplar Wood at Moderate Conditions
- Structure and Reactivity of Lignins and Associated Phenolic Acids in Wheat Straw TMP and CTMP Pulps
- Thermal Reactions of N-Methyl-morpholine-N-oxide (NMMO): A General Method for Separation and Quantification of N-Methyl-morpholine-N-oxide and its Main Degradation Products N-Methylmorpholine and Morpholine by Capillary Electrophoresis (CE)
- The Kismet of Residual During LMS Delignification of High-Kappa Kraft Pulps
- Variations in Transverse Fibre Wall Properties: Relations Between Elastic Properties and Structure
- Application of the GAB Sorption Isotherm Model to Klinki Pine (Araucaria klinkii Lauterb.)
- Strain Changes on the Inner Bark Surface of an Inclined Coniferous Sapling Producing Compression Wood
- Effects of Chemical Modification Reagents on Acoustic Properties of Wood
- J.L. McCarthy In Memoriam
- Acknowledgement
