Lignin Chemistry (Topics in Current Chemistry Collections)

Contents
Lignin-Based Composite Materials for Photocatalysis and Photovoltaics
	Abstract
	1 Introduction
	2 Native Versus Processed Lignin
		2.1 Sources
		2.2 Classification of Lignin
		2.3 Extraction of Lignin
			2.3.1 Sulfite Process
			2.3.2 Soda Process
			2.3.3 Kraft Process
			2.3.4 Organosolv Process
		2.4 Properties of Lignin
	3 General Applications of Lignin
		3.1 Synthesis of Materials from Lignin
	4 Overview of Carbon-Based Materials in Photocatalysis and Photovoltaics
		4.1 Lignin-Based Composites in Photocatalysis
			4.1.1 Preparation Techniques of Lignin-Based Composite Photocatalyst
			4.1.2 Chemical Interaction Between Lignin and Semiconductor
			4.1.3 Applications of Lignin-Based Composites in Photocatalysis
		4.2 Applications of Lignin-Based Materials in Photovoltaics
	5 Conclusions, Future Perspectives, and Challenges
	Acknowledgements
	References
Degradation of Vanillin During Lignin Valorization Under Alkaline Oxidation
	Abstract
	1 Introduction
	2 Methods
		2.1 Materials
		2.2 Alkaline Oxidation
		2.3 Analysis Methods
			2.3.1 High-Performance Liquid Chromatography (HPLC)
			2.3.2 Liquid Chromatography–Electrospray Mass Spectrometry (LC–MS)
			2.3.3 Gel Permeation Chromatography (GPC)
			2.3.4 Gas Chromatography–Mass Spectrometer (GC–MS)
			2.3.5 Heteronuclear Single Quantum Coherence (2D HSQC NMR)
			2.3.6 Calculation Formulas
	3 Results and Discussion
		3.1 Alkaline Oxidation of Pine Lignin
		3.2 Alkaline Oxidation of Vanillin
			3.2.1 Temperature
			3.2.2 Time
			3.2.3 Stirring Speed, O2 Pressure, and Alkali Concentration
			3.2.4 Catalyst
		3.3 Analysis of Unknown Products
		3.4 Presumable Mechanism of Vanillin Degradation
	4 Conclusions
	Acknowledgements
	References
Perspective on Lignin Oxidation: Advances, Challenges, and Future Directions
	Abstract
	1 Introduction
	2 Overview of Lignin Oxidation Research
		2.1 Oxidation of Dimeric Model Compounds
			2.1.1 Oxidative Cleavage of Non-oxidized Dimeric Structures
			2.1.2 Oxidation of Side-Chain Alcohol Groups in Dimeric Structures
			2.1.3 Cleavage of Oxidized Dimeric Structures
		2.2 Oxidation of Isolated Lignin Substrates
	3 Challenges in Lignin Oxidation
		3.1 Substrate-Related Challenges
		3.2 Catalyst- and Process-Related Challenges
	4 Future Directions
	Acknowledgements
	References
Thermosetting Polymers from Lignin Model Compounds and Depolymerized Lignins
	Abstract
	1 Introduction
	2 Lignin Model Compounds
		2.1 Epoxy Resins
		2.2 Polyurethanes
		2.3 Phenol-Formaldehyde Resins—Polybenzoxazines
		2.4 Other Polymeric Materials
	3 Depolymerized Lignin Bio-oils
		3.1 Epoxy Resins
		3.2 Polyurethanes
		3.3 PF Resins
	4 Conclusion and Perspectives
	Acknowledgments
	References
Carbon Materials from Technical Lignins: Recent Advances
	Abstract
	1 Introduction
	2 Carbon fibers
		2.1 Lignin–lignin blends
		2.2 Lignin–cellulose blends
		2.3 Reinforcement
		2.4 Fractionation
		2.5 Chemical modification
			2.5.1 Acetylation
			2.5.2 Iodine pretreatment
		2.6 New types of lignin
	3 Carbon adsorbents
		3.1 Carbonization
		3.2 Physical activation
		3.3 Chemical activation
		3.4 Template Synthesis
		3.5 Hydrothermal Carbonization
	4 Porous CF
		4.1 Carbonization
		4.2 Physical Activation
		4.3 Chemical Activation
	5 Carbon Catalysts
		5.1 Esterification
		5.2 Cellulose Hydrolysis
		5.3 Ethyl Tert-Butyl Ether Synthesis (Etherification)
		5.4 Decomposition of 2-Propanol
	6 Electrodes for Electrochemical Applications
		6.1 Hydrogen Electrosorption
		6.2 Electrical Double Layer Capacitors (EDLC)
		6.3 Li-Ion Batteries
		6.4 Na-Ion Batteries
	7 Other Carbon Materials
		7.1 Graphitic Carbons
		7.2 Glassy Carbon
		7.3 Carbon Black
	8 Conclusions
	Acknowledgements
	References
Catalytic Strategies Towards Lignin-Derived Chemicals
	Abstract
	1 Introduction
	2 Lignocellulosic Biomass
	3 Lignin Chemistry During Biomass Fractionation
		3.1 Base-Catalyzed Fractionation
			3.1.1 Application and Mechanism
			3.1.2 Kraft Pulping
			3.1.3 Sulphite Pulping
			3.1.4 Soda Pulping
		3.2 Acid-Catalyzed Fractionation
			3.2.1 Application and Mechanism
			3.2.2 Concentrated Acid Hydrolysis (CAH)
			3.2.3 Dilute Acid Hydrolysis (DAH)
		3.3 (Aqueous) Organosolv Fractionation
	4 Are Traditional Lignin Streams a Promising Feedstock for the Production of Chemicals?
		4.1 Considerations on the Isolation and Analysis of Lignin
		4.2 Depolymerization of Traditional Lignin
			4.2.1 Reductive Depolymerization
			4.2.2 Oxidative Depolymerization
			4.2.3 Acid- or Base-Catalyzed Depolymerization
			4.2.4 Solvolytic Depolymerization
			4.2.5 Thermal Depolymerization Through Fast-Pyrolysis
		4.3 Closing Remarks on Traditional Lignin Valorization
	5 Innovative Lignin Streams: Preserving β-O-4 Bonds During Fractionation
		5.1 Mild Fractionation: Passive Approach
			5.1.1 Ammonia
			5.1.2 Ionic Liquids
			5.1.3 Flow-Through Reactor Setups for Acid Hydrolysis
			5.1.4 γ-Valerolactone
			5.1.5 Mechanical Pretreatment
		5.2 Chemical Stabilization During Fractionation: Active Approach
	6 Depolymerization of Native Lignin to Stable Monomers
		6.1 Reductive Catalytic Fractionation (RCF)
		6.2 Reductive One-Pot Processing
		6.3 Oxidative Catalytic Fractionation (OCF)
		6.4 Other Opportunities Towards Higher Lignin Monomer Yields from Native Lignin
			6.4.1 Thermal (Fast-Pyrolysis)
			6.4.2 Solvolytic
			6.4.3 Base-Catalyzed
			6.4.4 Acid-Catalyzed
	7 Perspective on Lignin-Derived Chemicals
		7.1 Direct Utilization
		7.2 Chemocatalytic Upgrading
		7.3 Biocatalytic Upgrading
	8 Conclusions
	Acknowledgements
	References
Lignin Depolymerization to BTXs
	Abstract
	1 Introduction
	2 State of the Art
	3 Plant Lignin Structure
	4 Extraction and Isolation of Lignin. Repolymerization Phenomenon
	5 Strategies for Lignin Conversion
		5.1 Basic and Acid-Catalyzed Depolymerization
		5.2 Oxidative Depolymerization
		5.3 Ionic-Liquid Catalyzed Depolymerization
	6 Heterogeneous Catalysis Depolymerization
		6.1 Deoxygenation from Lignin (One step)
		6.2 Deoxygenation from Bio-oil or Target Oxygenated Compounds (two steps)
	7 Enzymatic Depolymerization
	8 Future Perspectives
	Acknowledgements
	References
Heterogeneous Catalyzed Thermochemical Conversion of Lignin Model Compounds: An Overview
	Abstract
	1 Introduction
		1.1 Biomass Pretreatment
			1.1.1 Kraft Lignin
			1.1.2 Alkali-Pulping Lignin
			1.1.3 Sulfite Process Lignin
			1.1.4 Steam Explosion
			1.1.5 Organosolv Lignin
			1.1.6 Acid-Hydrolysis Lignin
			1.1.7 Enzymatic-Hydrolysis Lignin
		1.2 Lignin Thermochemical Conversion
		1.3 Lignin Model Compounds
		1.4 Heterogeneous Catalysis
		1.5 Overview and General Considerations for This Review
	2 Reductive Conversion Processes
		2.1 Hydroprocessing of Lignin Model Compounds
			2.1.1 Monomers
			2.1.2 Dimers
		2.2 Catalytic Transfer Hydrogenation of Lignin Model Compounds
			2.2.1 Monomers
			2.2.2 Dimers
	3 Oxidative Conversion Processes
		3.1 Monomers
		3.2 Dimers
	4 Pyrolytic Processes
		4.1 Monomers
		4.2 Dimers
		4.3 Reforming of Lignin Pyrolysis Oil Model Compounds
	5 Hydrolytic Processes
	6 Overview and Future Perspectives
	References