Biochemical Conversion Of Lignocellulosic Biomass To Hydrocarbon Fuels And Products 2022 State Of Technology And Future Research

The annual State of Technology (SOT) assessment is a key activity for biochemical platform research. It allows the impact of research progress (both directly achieved in-house at the National Renewable Energy Laboratory [NREL] and indirectly extrapolated from available public data) to be quantified in terms of economic improvements in the overall cellulosic biofuel production process for a particular conversion pathway. As such, initial benchmarks can be established for currently demonstrated performance and progress can be tracked toward out-year goals to ultimately demonstrate cost-competitive biofuel technology. Building upon efforts to progress NREL's biochemical platform R&D work toward ultimate 2030 goals to demonstrate less than $2.50/gallon gasoline equivalent (GGE) fuel selling prices, experimental and techno-economic analysis (TEA) activities have primarily focused on "advanced" biochemical processing strategies to fuels and coproducts, guided by TEA modeling to highlight key barriers and priorities toward achieving this goal across a number of potential bioconversion pathways. The purpose of the present effort is to benchmark the latest experimental developments for these pathways as quantified by modeled minimum fuel selling prices (MFSPs), as a measure of current status relative to those final targets. For this SOT, TEA models were run for two separate biological conversion pathways to fuels, based on available data for integrated biomass deconstruction and hydrolysate processing; namely carboxylic acids (primarily butyric acid) and diols (2,3-butanediol [BDO]), reflecting NREL's recently published 2018 biochemical design report focused on those two pathways. The models were run across two scenarios for lignin utilization, namely combustion and conversion to value-added coproducts.

The purpose of this report is to benchmark the latest experimental developments across a number of potential bioconversion pathways as quantified by modeled minimum fuel selling prices (MFSPs), as a measure of current status relative to those final targets. For this state of technology, TEA models were run for two separate biological conversion pathways to fuels, based on available data for integrated biomass deconstruction and hydrolysate processing; namely carboxylic acids (primarily butyric acid) and diols (2,3-butanediol [BDO]), reflecting NREL's recently-published 2018 biochemical design report focused on those two pathways. The models were run across three scenarios for lignin utilization, namely combustion, conversion to coproducts based on "base case" performance with biomass hydrolysate, and conversion to coproducts based on "high" performance demonstrated with model lignin monomer components.

This book covers biomass modification to facilitate the industrial degradation processing and other characteristics of feedstocks and new technologies for the conversion of lignocelluloses into biofuels and other products.

Bioethanol has been recognized as a potential alternative to petroleum-derived transportation fuels. Even if cellulosic biomass is less expensive than corn and sugarcane, the higher costs for its conversion make the near-term price of cellulosic ethanol higher than that of corn ethanol and even more than that of sugarcane ethanol. Conventional process for bioethanol production from lignocellulose includes a chemical/physical pre-treatment of lignocellulose for lignin removal, mostly based on auto hydrolysis and acid hydrolysis, followed by saccharification of the free accessible cellulose portions of the biomass. The highest yields of fermentable sugars from cellulose portion are achieved by means of enzymatic hydrolysis, currently carried out using a mix of cellulases from the fungus Trichoderma reesei. Reduction of (hemi)cellulases production costs is strongly required to increase competitiveness of second generation bioethanol production. The final step is the fermentation of sugars obtained from saccharification, typically performed by the yeast Saccharomyces cerevisiae. The current process is optimized for 6-carbon sugars fermentation, since most of yeasts cannot ferment 5-carbon sugars. Thus, research is aimed at exploring new engineered yeasts abilities to co-ferment 5- and 6-carbon sugars. Among the main routes to advance cellulosic ethanol, consolidate bio-processing, namely direct conversion of biomass into ethanol by a genetically modified microbes, holds tremendous potential to reduce ethanol production costs. Finally, the use of all the components of lignocellulose to produce a large spectra of biobased products is another challenge for further improving competitiveness of second generation bioethanol production, developing a biorefinery.

This report was developed as part of the U.S. Department of Energy's Bioenergy Technologies Office's (BETO's) efforts to enable the development of technologies for the production of infrastructure-compatible, cost-competitive liquid hydrocarbon fuels from lignocellulosic biomass feedstocks. The research funded by BETO is designed to advance the state of technology of biomass feedstock supply and logistics, conversion, and overall system sustainability. It is expected that these research improvements will be made within the 2022 timeframe. As part of their involvement in this research and development effort, the National Renewable Energy Laboratory and the Pacific Northwest National Laboratory investigate the economics of conversion pathways through the development of conceptual biorefinery process models and techno-economic analysis models. This report describes in detail one potential conversion process for the production of high-octane gasoline blendstock via indirect liquefaction of biomass. The processing steps of this pathway include the conversion of biomass to synthesis gas or syngas via indirect gasification, gas cleanup, catalytic conversion of syngas to methanol intermediate, methanol dehydration to dimethyl ether (DME), and catalytic conversion of DME to high-octane, gasoline-range hydrocarbon blendstock product. The conversion process configuration leverages technologies previously advanced by research funded by BETO and demonstrated in 2012 with the production of mixed alcohols from biomass. Biomass-derived syngas cleanup via reforming of tars and other hydrocarbons is one of the key technology advancements realized as part of this prior research and 2012 demonstrations. The process described in this report evaluates a new technology area for the downstream utilization of clean biomass-derived syngas for the production of high-octane hydrocarbon products through methanol and DME intermediates. In this process, methanol undergoes dehydration to DME, which is subsequently converted via homologation reactions to high-octane, gasoline-range hydrocarbon products.

The consumption of petroleum has surged during the 20th century, at least partially because of the rise of the automobile industry. Today, fossil fuels such as coal, oil, and natural gas provide more than three quarters of the world's energy. Unfortunately, the growing demand for fossil fuel resources comes at a time of diminishing reserves of these nonrenewable resources. The worldwide reserves of oil are sufficient to supply energy and chemicals for only about another 40 years, causing widening concerns about rising oil prices. The use of biomass to produce energy is only one form of renewable energy that can be utilized to reduce the impact of energy production and use on the global environment. Biomass can be converted into three main products such as energy, biofuels and fine chemicals using a number of different processes. Today, it is a great challenge for researchers to find new environmentally benign methodology for biomass conversion, which are industrially profitable as well. This book focuses on the conversion of biomass to biofuels, bioenergy and fine chemicals with the interface of biotechnology, microbiology, chemistry and materials science. An international scientific authorship summarizes the state-of-the-art of the current research and gives an outlook on future developments.

Lignocellulosic Biomass to Value-Added Products: Fundamental Strategies and Technological Advancements focuses on fundamental and advanced topics surrounding technologies for the conversion process of lignocellulosic biomass. Each and every concept related to the utilization of biomass in the process of conversion is elaborately explained, with importance given to minute details. Advanced level technologies involved in the conversion of biomass into biofuels, like bioethanol and biobutanol, are addressed, along with the process of pyrolysis. Readers of this book will become fully acquainted with the field of lignocellulosic conversion, from its basics to current research accomplishments. The uniqueness of the book lies in the fact that it covers each and every topic related to biomass and its conversion into value-added products. Technologies involved in the major areas of pretreatment, hydrolysis and fermentation are explained precisely. Additional emphasis is given to the analytical part, especially the established protocols for rapid and accurate quantification of total sugars obtained from lignocellulosic biomass. Includes chapters arranged in a flow-through manner Discusses mechanistic insights in different phenomena using colorful figures for quick understanding Provides the most up-to-date information on all aspects of the conversion of individual components of lignocellulosic biomass

This book focuses on the technologies developed for the conversion of all three biomass components, i.e. cellulose, hemicellulose and lignin, and their constituents, to fuels and high-value products. Both biochemical and thermochemical approaches are reviewed. Additionally, the developed technologies are described in detail and their potential applications as well as their commercial status are discussed. The early attempts to produce fuel ethanol from lignocellulosic biomass feedstock focused solely on the biological conversion of cellulose because the only organism that had been used successfully for commercial production of ethanol, i.e. Saccharomyces cerevisiae, could only ferment glucose, which was obtained from the hydrolysis of cellulose. Hemicellulose and lignin were considered as wastes in these processes and were normally removed in pretreatment processes to enhance enzymatic hydrolysis of the remaining cellulose. However, this approach was not economically feasible and as a result, the biorefinery concept was developed. In a biorefinery, in addition to ethanol, various higher-value products are produced from hemicellulose and lignin, which were previously not considered. Consequently, technologies were developed for the fractionation of biomass and conversion of hemicellulose and lignin to fuels and high-value products to improve the economic feasibility. Written and edited by a team of investigators with many years of experience in biomass processing research and development, this book is an informative resource for postgraduate students and researchers interested in biorefinery and biofuel technologies both in academia- and commercial laboratories.