With the increasing demand of energy world over and depleting reserves of con­ventional fossil fuel, there has been growing global interest in developing alternative sources of energy. Also, there has been con­cern in growing economies with energy secu­rity. Biofuels offer much promise on these frontiers. In addition to above, they also offer benefits on environmental impact in compar­ison to fossil fuels. The present book provides state-of-the-art information on the status of the biofuel production and related aspects and also identifies the future R&D directions and perspectives.

The book has five sections. Section I is gen­eral and presents four chapters which deal with the principles of biorefineries, life cycle assessment of biofuels, thermochemical con­version of biomass to biofuels, and biomass- derived syngas fermentation into biofuels. Section II deals with different aspects of the production of second-generation bioethanol from lignocellulosic feedstocks. The first chapter in this section is introductory, giving state-of-the-art information on the status and perspectives; this is followed by a chapter on techno-economic analysis of lignocellu — losic bioethanol. Subsequent chapters deal with the different aspects of bioconversion process such as the pretreatment of ligno — cellulosic biomass, production of cellulo­lytic and hemicellulolytic enzymes for the hydrolysis of lignocellulosic biomass, hydro­lysis oflignocellulosic biomass, production of bioethanol from agro-industrial residues as feedstocks, and removal of inhibitory compounds from lignocellulosic hydrolyzates for bioethanol production. Section IIIA presents state-of-the-art information on the production of second-generation biodiesel from oilseeds. In this, the first chapter is intro­ductory and presents current perspectives and future, followed by the biotechnological methods to produce biodiesel, biodiesel pro­duction in supercritical fluids, biodiesel pro­duction using palm oil, and biodiesel from waste oil. Section IIIB contains chapters deal­ing with the production of third-generation biofuels from algal sources. The first chapter in this section as usual presents the current perspectives and future, followed by life cycle assessment of algal biodiesel, and the cultiva­tion of algae in photobioreactors.

Section IV is devoted on the fourth — generation biofuels, that is, biohydrogen. The section has five chapters and the first one gives general information with current perspectives and future. The other chapters are on biohydrogen production from bio-oils and industrial effluents, thermophilic biohydrogen production, and biohydrogen production with high-rate bioreactors. Section V provides two articles on the produc­tion of biobutanol and production of green liq­uid hydrocarbon fuels.

We thank the authors of all the chapters for their cooperation and also for their prepared­ness in revising the manuscripts in a time­framed manner. We also acknowledge the help from the reviewers, who in spite of their busy professional activities helped us by evaluating the manuscripts and gave their critical inputs to refine and improve the chapters. We warmly thank Dr. Marinakis Kostas and Dr. Anita Koch and the team of Elsevier for their cooperation and efforts in producing this book.

We sincerely hope that the current dis­course on biofuels R&D would go a long way in bringing out the exciting technological possibilities and ushering the readers toward the frontiers of knowledge in the area of biofuels.

The text in all the chapters is supported by numerous clear, informative diagrams and tables. The book would be of great interest to the postgraduate students and researchers of applied biology, biotechnology, microbiol­ogy, biochemical, and chemical engineers working on biofuels.

Ashok Pandey Christian Larroche Steven Ricke Claude-Gilles Dussap Edgard Gnansounou Editors