This book focuses on the technologies developed for the conversion of all three biomass components, i.e. cellulose, hemicellulose and lignin, and their constituents, to fuels and high-value products. Both biochemical and thermochemical approaches are reviewed. Additionally, the developed technologies are described in detail and their potential applications as well as their commercial status are discussed.
The early attempts to produce fuel ethanol from lignocellulosic biomass feedstock focused solely on the biological conversion of cellulose because the only organism that had been used successfully for commercial production of ethanol, i.e. Saccharomyces cerevisiae, could only ferment glucose, which was obtained from the hydrolysis of cellulose. Hemicellulose and lignin were considered as wastes in these processes and were normally removed in pretreatment processes to enhance enzymatic hydrolysis of the remaining cellulose.
However, this approach was not economically feasible and as a result, the biorefinery concept was developed. In a biorefinery, in addition to ethanol, various higher-value products are produced from hemicellulose and lignin, which were previously not considered. Consequently, technologies were developed for the fractionation of biomass and conversion of hemicellulose and lignin to fuels and high-value products to improve the economic feasibility.
Written and edited by a team of investigators with many years of experience in biomass processing research and development, this book is an informative resource for postgraduate students and researchers interested in biorefinery and biofuel technologies both in academia- and commercial laboratories.
Author(s): Nhuan Phu Nghiem, Tae Hyun Kim, Chang Geun Yoo
Publisher: Springer
Year: 2022
Language: English
Pages: 247
City: Cham
Preface
Contents
About the Editors
1 Introduction
References
2 Fractionation Strategies
2.1 Introduction
2.2 Fractionation vs. Pretreatment
2.2.1 Fractionation and Pretreatment in the Biorefinery Concept
2.2.2 Desirable Fractionation Process Design
2.3 Fractionation Processes
2.3.1 Cellulose-First Fractionation Methods
2.3.2 Hemicellulose-First Fractionation Methods
2.3.3 Lignin-First Fractionation Methods
2.4 Fates of Biomass Components upon Process Options and Designs
2.4.1 Fates of Components by Fractionation Methods
2.4.2 Fates of Components According to the Process Designs
2.5 Fractionation Strategies for Future Commercial Biorefinery
2.5.1 Valorization of Biomass Constituents Produced from Fractionation Process
2.5.2 Effective Strategies for Enhanced Values in Large-Scale Production
References
3 Biochemical Conversion of Cellulose
3.1 Introduction
3.2 Biorefinery Technologies for Lignocellulosic Biomass Conversion
3.3 Primary Factors for Effective Enzymatic Hydrolysis
3.3.1 Types of Enzymes
3.3.2 Enzyme Accessibility to Cellulose
3.3.3 Solids (Cellulose Substrate) Concentration
3.4 Inhibitors of Cellulase Enzymes
3.4.1 Cellulose–Hemicellulose–Iignin-Derived Soluble Inhibitors
3.4.2 Enzyme Interactions with Lignin
3.5 Strategies to Improve Enzymatic Hydrolysis of Cellulose
3.5.1 Enzyme Cocktail Optimization
3.5.2 Conditioning/Removal of Soluble Inhibitory Compounds
3.5.3 Chemical/Biological Detoxification with Additives
3.5.4 Surface Hydrophobicity Modification of Lignin and Cellulases
3.6 Microbial Fermentation of Lignocellulose for Biofuels and Biochemicals
3.6.1 Biofuels—Ethanol
3.6.2 Hydrogen
3.6.3 Other Applications for Biochemical Production
3.6.4 Future Prospects
References
4 Biochemical Conversion of Hemicellulose
4.1 Hemicellulose Fractionation for Biochemical Conversion
4.2 Hemicellulose Fermentation to Bioethanol
4.3 Hemicellulose Fermentation to Organic Acids
4.4 Hemicellulose Fermentation to Other Value-Added Co-products
4.4.1 Astaxanthin
4.4.2 Xylitol
4.4.3 2,3-Butanediol
4.5 Conclusion
References
5 Biochemical Conversion of Lignin
5.1 Overview
5.2 Lignin Biotransformation
5.2.1 Depolymerization
5.2.2 Monomer Funneling
5.2.3 Potential Products
5.3 Future Research and Potential Commercial Implementation
5.3.1 Feedstock Development
5.3.2 Production of Lignin-Depolymerizing Enzymes
5.3.3 Lignin Depolymerization Kinetics
5.3.4 Fermentation Development
5.3.5 Process Integration
5.4 Conclusion
References
6 Thermochemical Conversion of Cellulose and Hemicellulose
6.1 Introduction
6.2 Cellulose
6.3 Hemicellulose
6.4 Combustion
6.4.1 Combustion of Cellulose
6.4.2 Recent Applications of Cellulose Combustion
6.4.3 Combustion of Hemicellulose
6.5 Pyrolysis
6.5.1 Slow Pyrolysis
6.5.2 Fast Pyrolysis
6.5.3 Flash Pyrolysis
6.5.4 Pyrolysis of Cellulose
6.5.5 Pyrolysis of Hemicellulose
6.6 Liquefaction
6.6.1 Liquefaction of Cellulose
6.6.2 Liquefaction of Hemicellulose
6.7 Gasification
6.7.1 Gasification of Cellulose
6.7.2 Gasification of Hemicellulose
6.8 Conclusion
References
7 Thermochemical and Catalytic Conversion of Lignin
7.1 Introduction
7.2 Lignin Structure and Types
7.3 Pyrolysis of Technical Lignins
7.3.1 Pyrolysis of Neat Lignins
7.3.2 Pyrolysis of Lignin with Additives
7.3.3 Catalytic Pyrolysis of Lignin
7.4 Solvent Phase Lignin Depolymerization
7.4.1 Non-catalytic Solvent Liquefaction
7.4.2 Base-Catalyzed Depolymerization
7.4.3 Acid-Catalyzed Depolymerization
7.4.4 Reductive Depolymerization
7.4.5 Reductive Depolymerization by Transfer Hydrogenation
7.4.6 Oxidative Depolymerization
7.4.7 “Lignin-First” in situ Depolymerization
7.5 Downstream Processing: Separations and Upgrading
7.6 Summary and Outlook
References
8 Material Applications of Lignin
8.1 Introduction
8.2 Lignin-Based Composite Materials
8.2.1 Fabrication Methods of Lignin-Based Composites
8.2.2 Impacts of Lignin on the Properties of Lignin-Based Composites and Their Applications
8.3 Lignin-Based Hydrogels
8.3.1 Synthesis Methods of Lignin-Based Hydrogels
8.3.2 Applications of Lignin-Based Hydrogels
8.4 Conclusion and Future Perspectives
References
9 Techno-Economic Analysis for Evaluating Biorefinery Strategies
9.1 Introduction
9.2 Techno-Economic Analysis (TEA)
9.3 TEA of Lignocellulosic Biomass-Based Biorefineries
9.4 TEA of Engineered Lipid-Producing Energy Crops-Based Biorefineries
9.5 Summary
References
