tailieunhanh - Handbook of plant based biofuels - Chapter 11

11 Bioethanol from Lignocellulosic Biomass Part III Hydrolysis and Fermentation Ramakrishnan Anish and Mala Rao contents Abstract 159 Introduction 160 Hydrolysis of Lignocellulosic Biomass 160 Acid Hydrolysis . 160 Dilute Acid Hydrolysis . 160 Concentrated Acid Hydrolysis . 162 Enzymatic Hydrolysis of Lignocellulosic Biomass 163 Factors Governing Enzymatic Hydrolysis 164 Detoxification. | 11 Bioethanol from Lignocellulosic Biomass Part III Hydrolysis and Fermentation Ramakrishnan Anish and Mala Rao CONTENTS Hydrolysis of Lignocellulosic Acid Dilute Acid Hydrolysis. 160 Concentrated Acid Enzymatic Hydrolysis of Lignocellulosic Factors Governing Enzymatic Biological Detoxification Physical Detoxification Chemical Detoxification Fermentation of Lignocellulosic Biomass to Separate Hydrolysis and Fermentation SHF .167 Direct Microbial Conversion DMC .167 Simultaneous Saccharification and Fermentation SSF .168 Recombinant DNA Conclusions and Future References. 170 ABSTRACT Lignocellulose is the most abundant natural renewable resource and is one of the preferred choices for the production of bioethanol. As a substrate for bioethanol production it has a barrier in its complex structure which resists hydrolysis. For lignocellulose to be amenable to fermentation treatments are necessary that release 159 2009 by Taylor Francis Group LLC 160 Handbook of Plant-Based Biofuels monomeric sugars which can be converted to ethanol by microbial fermentation. The current state of the art on acid and enzymatic hydrolysis of lignocellulose and subsequent microbial fermentation to ethanol are described in this chapter. Approaches for detoxification of the lignocellulose hydrolysate for effective fermentation to ethanol are also discussed. INTRODUCTION The rapid depletion of fossil fuels coupled with the increasing demands for transportation fuels has necessitated research focus on alternative renewable energy sources. Lignocellulose is the most abundant renewable resource abundantly available for conversion to fuels. On a worldwide basis terrestrial plants .