Pulping and biorefining
- General approach and principles
- Extraction-based methods
- Separation of valuable extractives from trees
- Choosing the right solvent – hydrophobic or hydrophilic?
- Stemwood extractives-based products
- Operation modes and procedures in industrial extraction processes
- Exudate gums and latexes
- Hot-water extraction
- Wood extractives – general description
- Factors contributing to the loss of extractives
- Chemical changes in extractives during storage
- Bark extractives – terpenes and terpenoids
- Bark extractives – polyphenols and other minor compounds
- Use of deep eutectic solvents (DES)
- Chemical and biochemical conversion
- Thermochemical conversion
- Kraft pulping
- Wood material handling systems
- Pulping process-general approach
- Pulping technologies
- Drying of chemical pulps
- Chemical (market) pulps drying plant applications
- Recovery of cooking chemicals and by-products
- Integrated biorefinery concepts
- Oxygen-alkali delignification
- Delignifying or lignin-removing bleaching
- Other delignification methods
- Chemimechanical pulping
- Mechanical pulping
- Pulp characterisation and properties
Pyrolysis reactions – lignin There are three main product groups in lignin pyrolysates:1 large-molar-mass oligomers (i.e., pyrolytic lignins), monomeric phenolic compounds (e.g., phenols, hydroxylphenols, guaiacols and syringols) and light compounds (e.g., methanol and acetic acid). Devolatilisation and char formation are the two competing reactions, along with some subsequent secondary reactions. Char formation via crosslinking reactions
Authors & references
Author:
Raimo Alén, University of Jyväskylä
References:
- Zhu, X. and Lu, Q. 2010. Production of chemicals from selective fast pyrolysis of biomass. In: Momba, M. N. B. and Bux, F. (Eds.). Biomass. Sciyo, Croatia. Pp. 147−164.
- Hosoya, T., Kawamoto, H. and Saka, S. 2008. Secondary reactions of lignin-derived primary tar components. Journal of Analytical and Applied Pyrolysis 83(1):78−87.
- Vuori, A. I. and Bredenberg, J. B. 1987. Thermal chemistry pathways of substituted anisols. Industrial & Engineering Chemistry Research 26(2):359−365.
- Ghalibaf, M. 2019. Analytical Pyrolysis of Wood and Non-wood Materials from Integrated Biorefinery Concepts. Doctoral Thesis. University of Jyväskylä, Laboratory of Applied Chemistry, Jyväskylä, Finland. 106 p.
- Alén, R., Kuoppala, E. and Oesch, P. 1996. Formation of the main degradation compound groups from wood and its components during pyrolysis. Journal of Analytical and Applied Pyrolysis 36:137−148.
- Zhao, X. and Liu, D. 2010. Chemical and thermal characteristics of lignins isolated from Siam weed stem by acetic acid and formic acid delignification. Industrial Crops and Products 32(3):284−291.
- de Wild, P. J., Huijgen, W. J. J. and Heeres, H. J. 2012. Pyrolysis of wheat straw-derived organosolv lignin. Journal of Analytical and Applied Pyrolysis 93:95−103.
- Luo, Z., Wang, S. and Guo, X. 2012. Selective pyrolysis of organosolv lignin over zeolites with product analysis by TG-FTIR. Journal of Analytical and Applied Pyrolysis 95:112−117.
- Wang, S., Lin, H., Ru, B., Sun, W., Wang, Y. and Luo, Z. 2014. Comparison of the pyrolysis behavior of pyrolytic lignin and milled wood lignin by using TG-FTIR analysis. Journal of Analytical and Applied Pyrolysis 108:78−85.
- Collard, F. X. and Blin, J. 2014. A review on pyrolysis of biomass constituents: mechanisms and composition of the products obtained from the conversion of cellulose, hemicelluloses and lignin. Renewable & Sustainable Energy Reviews 38:594−608.
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This page has been updated 15.11.2020