Recent advances in bioconversion of lignocellulose to biofuels and value added chemicals within the biorefinery concept preface

Authors: Dien, Bruce; Slininger, Patricia - Pat

Submitted to: Elsevier
Publication Type: Book / Chapter
Publication Acceptance Date: 1/14/2020
Publication Date: 7/10/2020
Citation: Dien, B.S., Slininger, P.J. 2020. Recent advances in bioconversion of lignocellulose to biofuels and value added chemicals within the biorefinery concept preface. Elsevier. 2020: xv-xvii. https://doi.org/10.1016/B978-0-12-818223-9.00019-9.
DOI: https://doi.org/10.1016/B978-0-12-818223-9.00019-9

Interpretive Summary:

Technical Abstract: This is a timely book because the need to confront climate change in a meaningful manner has never been greater. The most recently released IPCC report details the lack of progress in abating greenhouse gas (GHG) emissions and the greater than predicted impacts of climate change over the past decade [1]. There is also an increased risk of “crossing critical tipping points” that will cause irrevocable changes [2]. Bioenergy and especially biofuels are urgently needed to address climate change [3,4]. Great strides have been made in lowering the cost of solar and wind power and in commercializing electrical vehicles. Yet the effort required to decarbonize our fuel supply is daunting. Presently 85% of energy originates from fossil fuels and energy consumption is expected to grow, driven by population growth and changes in living standards [5]. Even with international pledges and a growing public consensus on the threat of Climate Change, the rate of annual greenhouse gas emissions continues to increase [5]. Therefore, every tool for GHG abatement needs to be used; as is proposed in IPCC mitigations scenarios [1]. Liquid biofuels complement electrical energy and can decarbonize ships, planes, and legacy vehicles; and, currently, there are many more cars equipped with internal combustion engines than with electrical motors [1]. Furthermore, it is estimated that solely in the United States over 1 billion tons per year of biomass can be made available for production of bioenergy and chemicals [6]. The agricultural sector will be challenged by climate change [2,7]. Warming seasons and increased extreme weather events will directly impact production and logistics. It is desirable, therefore, that the agricultural community be included in any mitigation effort. Biorefineries and possible carbon credits will serve to strengthen rural economics and help farmers in their efforts to confront future climate related challenges [3]. This book outlines recent research in developing advanced biofuels and chemicals with near term applications. There is a strong emphasis on biomass hydrolyzing enzymes; both production and application to biomass. This emphasis is warranted because enzymes are a major cost and economic risk for production of biomass sugars. Also, minimizing generation of enzyme and fermentation inhibitors, while affording more concentrated sugars benefits the entire process, especially fermentation and distillation. Fortunately, it is an area of research that has made tremendous strides in the last decade, which has made possible numerous reports of greatly increased sugar and ethanol concentrations. The book also emphasizes co-products, including those specific to lignin. Refiners depend on co-products for profitability. Petroleum refiners make more money marketing chemicals than gasoline. Likewise, corn ethanol manufacturers would be unprofitable without distillers’ grains and, for wet millers, food and feed ingredients and chemicals. Co-products help producers withstand volatility in the fuel market and spread out core capital costs. There is a special need for new co-products derived from lignin, which can make up as much as one-third of the biomass weight. Multiple co-product streams with recycle loops for increased efficiency make for complex facilities, which is addressed by a chapter on virtual biorefineries. Yet just covering technological aspects is insufficient because of great financial and technical risks for biorefinery pioneers. Building a cellulosic ethanol plant is much more expensive than a corn ethanol plant (e.g. $9.62 - $17.78 per annual gal of ethanol [8]), and favorable governmental policies will be required to lower investment risks. Therefore, it is essential to understand what benefits future biorefineries will bring to rural economies and standards of living. Still from a societal perspective, advan