Cereal Straw as a Resource for Sustainable Biomaterials and Biofuels

Materials from renewable resources are receiving increased attention, as leading industries and manufacturers attempt to replace declining petrochemical-based feedstocks with products derived from natural biomass, such as cereal straws. Cereal straws are expected to play an important role in the shift toward a sustainable economy, and a basic knowledge of the composition and structure of cereal straw is the key to using it wisely.
Cereal Straw as a Resource for Sustainable Biomaterials and Biofuels: Chemistry, Extractives, Lignins, Hemicelluloses and Cellulose provides an introduction to straw chemistry. Topics discussed include the structure, ultrastructure, and chemical composition of straw; the structure and isolation of extractives from the straw; the three main components of straw: cellulose, hemicelluloses, and lignins; and chemical modifications of straw for industrial applications.
This book will be helpful to scientists interested in the areas of natural resource management, environmental chemistry, plant chemistry, material science, polysaccharide chemistry, and lignin chemistry. It will also be of interest to academic and industrial scientists/researchers interested in novel applications of agricultural residues for industrial and/or recycling technologies.

•  Provides the basics of straw composition and the structure of its cell walls

• Details the procedures required to fractionate straw components to produce chemical derivatives from straw cellulose, hemicelluloses, and lignins

• Elucidates new techniques for the production of biodegradable materials for the energy sector, chemical industry, and pulp and paper business

   

Scientists with research interests in the areas of natural resource management, environmental chemistry, plant chemistry, material science, polysaccharide chemistry, lignin chemistry, etc, as well as academic and industrial researchers with an interest in using agricultural residues as novel products for industry and/or recycling technologies

Preface

1. Introduction

References

2. Structure, Ultrastructure, and Chemical Composition

2.1 Anatomical Structure

2.2 Ultrastructure

2.2.1 Ultrastructure of Wood

2.2.2 Ultrastructure of Grass

2.3 Distribution of Polysaccharides and Lignin

2.3.1 Polysaccharides Distribution

2.3.2 Lignin Distribution

2.4 Chemical Composition

2.4.1 Cellulose

2.4.2 Hemicelluloses

2.4.3 Lignin

2.4.4 Pectic Substances

2.4.5 Proteins

2.4.6 Cutins, Suberins, Waxes and Other Extracts

2.4.7 Ash

References

3. Extractives

3.1 Isolation and Purification

3.1.1 Procedures for Isolation of Extractives

3.1.2 Purification of Extractives

3.2 Structural Characterization

3.2.1 Chemical Composition of Extractives

3.2.2 Spectroscopic and Thermal Characterization

References

4. Hemicelluloses

4.1 Introduction

4.2 Occurrence, Nature, and Classification

4.2.1 Occurrence, Nature, and Classification of Hemicelluloses

4.2.2 Occurrence, Nature, and Classification of Straw Hemicelluloses

4.3 Isolation, Analysis, and Structure

4.3.1 Isolation

4.3.2 Structural Analysis of Straw Hemicelluloses

4.3.3 Structure

4.4 Physicochemical Properties

4.4.1 Solubility

4.4.2 Mw and Mw Distribution

4.4.3 Rheological Behavior

4.4.4 Surface Tension

4.4.5 Thermal Behavior

4.4.6 Biological Activity

4.5 Interactions with Cellulose

4.5.1 Interaction of Hemicelluloses with Celluloses in Production of Celluloses

4.5.2 Interaction of Hemicelluloses with Celluloses in Papermaking Process

4.5.3 Effect of Interaction of Hemicelluloses with Celluloses on the Bioethanol Production

4.5.4 The Assembly Characteristics of Hemicelluloses on Cellulose

4.6 Modification of Hemicelluloses and its Application

4.6.1 The Potential Modification of Hemicelluloses

4.6.2 Chemical Modification and its Application

4.6.3 Straw Hemicelluloses and their Application

4.7 Summary

References

5. Cellulose

5.1 Occurrence

5.2 Isolation

5.2.1 Delignification and Alkali Extraction

5.2.2 Steam Explosion

5.2.3 Alkaline Peroxide Extraction

5.2.4 Organic Solvent Extraction

5.2.5 Other Isolation Methods

5.3 Structure and the Crystalline Lattice of Cellulose I

5.3.1 Supermolecular Structure

5.3.2 Cellulose Lattice I

5.3.3 Conversion of Cellulose I to Cellulose II

5.4 Physico-Chemical Properties

5.4.1 Structural Properties

5.4.2 Dissolution of Cellulose

5.4.3 Regeneration of Cellulose

5.4.4 Hydrolysis of Cellulose

5.5 Chemical Modification and its Utilization

5.5.1 Acetylation

5.5.2 Acylation with Other Linear Anhydrides or Chlorides

5.5.3 Esterification with Cyclic Anhydrides

5.5.4 Carboxymethylation

5.5.5 Other Chemical Modification

5.6 Concluding Remarks

References

6. Lignin

6.1 Introduction

6.2 Monolignols, and Lignification in Grass Cell Walls

6.2.1 Biosynthesis of Monolignols

6.2.2 Lignin Deposition and Topochemistry

6.2.3 Lignification – Polymerization of Monolignols

6.3 Isolation and Purification of Lignins

6.3.1 Milled Wood Lignin

6.3.2 Enzyme Lignin

6.3.3 Alkali Lignins

6.3.4 Organosolv Lignin

6.3.5 Purification of Lignins

6.4 Analytical Methods for Lignin Characterization

6.4.1 Thioacidolysis

6.4.2 DFRC Method

6.4.3 Nuclear Magnetic Resonance Spectroscopy

6.5 Structural Characteristics of Straw Lignins

6.5.1 Ferulates in Grass Lignins

6.5.2 p-Coumarates in Grass Lignins

6.5.3 Lignin–Carbohydrate Complexes in Grasses

6.6 Utilization of Lignins

6.6.1 Wood Adhesives Made from Lignins

6.6.2 Biochemicals/Biofuel from Lignins

6.7 Concluding Remarks

References

7. Chemical Modification of Straw as Novel Materials for Industries

7.1 Chemical Modification of Cereal Straws as Natural Sorbents in Oil Spill Cleanup

7.1.1 Hazard of Oil Spill

7.1.2 Methods for Controlling Oil Spills

7.1.3 Classification of Oil Sorbents

7.1.4 Principles of Sorbency

7.1.5 Influence of Sorptive Capacity

7.1.6 Chemical Modification of Cereal Straws as Oil Sorbents

7.1.7 Types of Catalysts in Chemical Modification

7.1.8 Agro-Based Sorbent Application

References

7.2 Modification of Cereal Straws as Natural Sorbents for Removing Metal Ions from Industrial Waste Water

7.2.1 Introduction

7.2.2 Mechanism of Metal Biosorption

7.2.3 Adsorption Models

7.2.4 Methods of Chemical Modification

7.2.5 Chemically Modified Straw

7.2.6 Summary

References

7.3 Modification of Straw for Activated Carbon Preparation and Application for the Removal of Dyes from Aqueous Solutions

7.3.1 Introduction

7.3.2 Technologies Available for Dye Removal

7.3.3 Dye Removal Using Commercial Activated Carbons

7.3.4 Dye Removal Using Agricultural Wastes or Byproducts

7.3.5 Production of Acs from Agricultural Byproducts

7.3.6 Summary

References 248

7.4 Liquefaction and Gasification of Cereal Straws

7.4.1 Hydrothermal Liquefaction

7.4.2 Solvolytic Liquefaction

7.4.3 Thermal Gasification

7.4.4 Hydrothermal Gasification

References

7.5 Biorefinery Straw for Bioethanol

7.5.1 Introduction

7.5.2 Lignocellulosic Biomass Recalcitrance

7.5.3 Biorefinery Straw for Bioethanol Production

7.5.4 Summary

References

Index