Lignin Valorization

Lignin, an aromatic biopolymer found in plant cell walls, is a key component of lignocellulosic biomass and generally utilized for heat and power. However, lignin’s chemical composition makes it an attractive source for biological and catalytic conversion to fuels and chemicals. Bringing together experts from biology, catalysis, engineering, analytical chemistry, and techno-economic/life-cycle analysis, Lignin Valorization presents a comprehensive, interdisciplinary picture of how lignocellulosic biorefineries could potentially employ lignin valorization technologies. Chapters will specifically focus on the production of fuels and chemicals from lignin and topics covered include (i) methods for isolating lignin in the context of the lignocellulosic biorefinery, (ii) thermal, chemo-catalytic, and biological methods for lignin depolymerization, (iii) chemo-catalytic and biological methods for upgrading lignin, (iv) characterization of lignin, and (v) techno-economic and life-cycle analysis of integrated processes to utilize lignin in an integrated biorefinery. The book provides the latest breakthroughs and challenges in upgrading lignin to fuels and chemicals for graduate students and researchers in academia, governmental laboratories, and industry interested in biomass conversion.

A comprehensive, interdisciplinary picture of how lignocellulosic biorefineries could potentially employ lignin valorization technologies.

Lignocellulosic biomass has great potentials as an alternative feedstock for fuels and chemicals. For effective utilization of biomass, biomass recalcitrance, which is inherent resistance of plant cell walls to biological deconstruction, needs to be reduced. Among many factors in biomass, lignin is significantly related to biomass recalcitrance. Lignin, a complex aromatic polymer, is the largest non-carbohydrate component (15-40% dry weight) in most terrestrial plants. In nature, it provides a structural integrity, facilitates water and nutrient transport, and protects plants from microbial attack. From a different angle, lignin significantly contributes to biomass recalcitrance, so it is necessary to reduce and/or modify the lignin for effective conversion of biomass. Genetic modifications of the lignin biosynthetic pathway and lignin-targeting pretreatments have been developed to minimize the lignin-induced biomass recalcitrance. High carbon content of lignin also renders it an attractive feedstock for many applications. About 100,000 to 200,000 tons of lignin can be generated per year as a byproduct from cellulosic ethanol production, so valorization of these lignins could be one of keys for achieving economic biorefinery. However, investigations of lignin conversion have not been accomplished as the utilization of carbohydrates in biomass. Depolymerization of lignin is still challenging because of its broad distribution of bond strengths, recondensation of low-molecular species, and poor product selectivity. Diverse biological and thermochemical depolymerization methods have been investigated to overcome these barriers. In this Research Topic, recent advancements in biomass recalcitrance by effective utilization of lignin are introduced.

The valorization of lignocellulosic biomass, in the form of forest and agricultural wastes, industrial processing side-streams, and dedicated energy crops, toward chemicals, fuels and added-value products has become a major research area with increasing exploitation potential. The efficient and tailored depolymerization of biomass or its primary structural components (hemicellulose, cellulose, and lignin) to platform chemicals, i.e., sugars, phenolics, furans, ketones, organic acids, etc. is highly dependent on the development of novel or modified chemo- and bio-catalytic processes that take into account the peculiarities and recalcitrance of biomass as feedstock, compared for example to petroleum fractions. The present Research Topic in Frontiers in Chemistry, Section of Green and Sustainable Chemistry, entitled “Nano-(bio)catalysis in lignocellulosic biomass valorization” aims to further contribute to the momentum of research and development in the (bio)catalytic conversion of biomass, by featuring original research papers as well as two review papers, authored and reviewed by experts in the field. The Research Topic addresses various representative reactions and processes in biomass valorization, highlighting the importance of developing novel, efficient and stable nano-(bio)catalysts with tailored properties according to the nature of the reactant/feedstock and the targeted products.

HANDBOOK of BIOMASS VALORIZATION for INDUSTRIAL APPLICATIONS The handbook provides a comprehensive view of cutting-edge research on biomass valorization, from advanced fabrication methodologies through useful derived materials, to current and potential application sectors. Industrial sectors, such as food, textiles, petrochemicals and pharmaceuticals, generate massive amounts of waste each year, the disposal of which has become a major issue worldwide. As a result, implementing a circular economy that employs sustainable practices in waste management is critical for any industry. Moreover, fossil fuels, which are the primary sources of fuel in the transportation sector, are also being rapidly depleted at an alarming rate. Therefore, to combat these global issues without increasing our carbon footprint, we must look for renewable resources to produce chemicals and biomaterials. In that context, agricultural waste materials are gaining popularity as cost-effective and abundantly available alternatives to fossil resources for the production of a variety of value-added products, including renewable fuels, fuel components, and fuel additives. Handbook of Biomass Valorization for Industrial Applications investigates current and emerging feedstocks, as well as provides in-depth technical information on advanced catalytic processes and technologies that enable the development of all possible alternative energy sources. The 22 chapters of this book comprehensively cover the valorization of agricultural wastes and their various uses in value-added applications like energy, biofuels, fertilizers, and wastewater treatment. Audience The book is intended for a very broad audience working in the fields of materials sciences, chemical engineering, nanotechnology, energy, environment, chemistry, etc. This book will be an invaluable reference source for the libraries in universities and industrial institutions, government and independent institutes, individual research groups, and scientists working in the field of valorization of biomass.

Explore the potential of biomass-based chemicals with this comprehensive new reference from leading voices in the field With the depletion of fossil raw materials a readily ascertainable inevitability, the exploitation of biomass-based renewable derivatives becomes ever more practical and realistic. In Biomass Valorization: Sustainable Methods for the Production of Chemicals, accomplished researchers and authors Davide Ravelli and Chiara Samori deliver a thorough compilation of state-of-the-art techniques and most advanced strategies used to convert biomass into useful building blocks and commodity chemicals. Each chapter in this collection of insightful papers begins by detailing the core components of the described technology, along with a fulsome description of its advantages and limitations, before moving on to a discussion of recent advancements in the field. The discussions are grouped by the processed biomass, such as terrestrial biomass, aquatic biomass, and biomass-deriving waste. Readers will also benefit from the inclusion of: A thorough introduction to the role of biomass in the production of chemicals An exploration of biomass processing via acid, base and metal catalysis, as well as biocatalysis A practical discussion of biomass processing via pyrolysis and thermochemical-biological hybrid processes A concise treatment of biomass processing assisted by ultrasound and via electrochemical, photochemical and mechanochemical means Perfect for chemical engineers, catalytic chemists, biotechnologists, and polymer chemists, Biomass Valorization: Sustainable Methods for the Production of Chemicals will also earn a place in the libraries of environmental chemists and professionals working with organometallics and natural products chemists.

This book provides an overview of the different aspects of microbial bioconversion methodologies for valorization of underutilized wastes of varied nature. It covers microbiological/biotechnological aspects, environmental concerns, bioprocess development, scale-up aspects, challenges, and opportunities in microbial valorization at commercial scale. It explains sustainable microbiological processes for bioconversion and valorization of the wastes for production of various products of commercial interests, including biofuels, bioenergy, and other platform chemicals. The book • presents potential biotechnological topics and strategies for the valuation of agricultural waste materials; • provides technical concepts on the production of various commercially significant bioproducts; • introduces various microbial bioprocesses to sustainably valorize various potential wastes as renewable feedstocks for production of biofuels and biochemicals; • explores the relevant scale-up opportunities, commercialization aspects, and critical technological advances; and • explains concepts and recent trends in life cycle analyses in waste valorization. It is aimed at researchers and graduate students in bioengineering, biochemical engineering, microbial technology/microbiology, environmental engineering, and biotechnology.

Enables readers to convert lignin using a variety of depolymerization methods and develop it into industrially relevant and functional compounds Depolymerization of Lignin to Produce Value Added Chemicals summarizes the depolymerization and utilization of lignin from different sources and covers the emerging field of biological depolymerization, enabling the reader to identify the high added value of a biomass residue and support him/her in its possible use for mass and niche high impact application sectors. Lignin has great potential to significantly improve the economics of a biorefinery due to its conversion into value-added products. To illustrate, this book includes information on: Feasibility of large-scale implementation of covered technologies, including thermal, biological, and chemical depolymerization, especially in relation to potential industrial applications "Lignin-first" biorefining approach, and potential applications of lignin-derived monomers and their derivatives as bioactives in food, natural health products, and pharmaceuticals Business and market scenarios and challenges that intersect with lignin, along with perspectives on lignin valorization Benefits and drawbacks of a lignin-first approach to biorefining, and techno-economic considerations of lignin and its applications Depolymerization of Lignin to Produce Value Added Chemicals is an essential resource for researchers, chemists, engineers, analysts, and consultants within universities, independent research organizations, and government.