Technologies for Biofuels and Green Chemistry Dr. Larry P. Walker Professor Department of Biological and Environmental Engineering Director of Cornell Biofuels Research Laboratory Cornell University
MAJOR PREMISE Agriculture will increasingly provide the raw materials and energy needed to drive our transition to a sustainable world.
Major Global Driver Biomass is the only renewable that directly reduces our dependency on liquid fuels.
EARLY PROPONENTS Henry Ford Rudolf Christian Karl Diesel
Policy: Energy Independence and Security Act (EISA) EISA establishes ambitious goals to more than triple overall U.S. biofuel use to 36 billion gallons by 2022, with cellulosic biofuels making up 16 billion gallons and on a trajectory to surpass corn-based ethanol use.
EISA Mandates
Reality check!
SCIENCE AND TECHNOLOGY ARE EVOLVING TO MEET THE CHALLENGES genomics proteomics protein engineering system biology molecular modeling nanobiotechnology advanced materials advanced bioreactors more sophisticated control systems advance systems engineering tools
LIGNOCELLULOSE TO ETHANOL PROCESS FLOW DIAGRAM Cellulase Production Cellulases Raw Cellulose Pretreatment Pretreated Cellulose Enzymatic Hydrolysis Energy Sugar Solution Utilities Fermentation Residue Residue Beer Ethanol Distillation
BIOMASS RESOURCES
PRETREATMENT Given the chemical and physical heterogeneity of plant cell wall it is necessary to pretreat the biomass prior to enzymatic conversion to do the following: Size reduction, Fractionation, Increase specific surface area, and Decrease the crystallinity of the substrate
Pretreatment Pretreatment Chemical pretreatment can reach high yields At environmental cost Sub-critical water suffers from: -Mass transfer limitations or -High water usage and dilution when flowthrough is used But Supercritical CO 2 saturated with water does not High P Dilute, low viscosity reaction Low P CO 2 Concentrated aqueous product solution
Method Method Batch pretreatment Starting pressure is set at about 60 bars. Final pressure is controlled by a regulator. Pretreatment will then be performed for 0, 10 and 20 min. Heating time is 10±1 minutes. Optimal conditions are determined with wood chips (<1mm) For comparison larger biomass particles ( 1cm) will be tested with optimal conditions. Other biomass tested with optimal conditions: Switchgrass, Sorghum, Reed canary grass and Corn Stover Volume heated 25ml Total volume 47ml
Results for 20 wt% solids Cellulose to glucose Hemicellulose to monomers Cellulose to 5-HMF Hemicellulose to furfural
MICROBIAL CELLULASE SOURCES Shipworm bacterium Cellulomonas fimi Clostridium thermocellum Acetivibrio cellulolyticus Trichoderma reesei Thermobifida fusca Plants Environmental Sample
CELL WALL ENZYME DISCOVERY Virulent Plant Pathogens Environmental Sample Dried switchgrass with disease symptoms. Fusarium graminearum Cochliobolus sativus Colletotrichum destructivum Phylosticta maydis Fusarium oxysporum Sclerotinia sclerotiorum
The engineer s goal is to design and to construct an environment to support the growth and activities of a microorganism. FERMENTATION
SACCHAROMYCES CEREVISIAE Model organism First eukaryotic genome to be fully sequenced, annotated, and made publicly available Prevalent in alcohol and food industry
MODELING APPROACH: RECONSTRUCTED METABOLIC NETWORKS Extensive knowledge base Computational method for organizing extensive data sets Established approach with growing research community Amenable to simulation Source: Feigenson, G. 2006 BIOBM 331
METABOLIC FUNCTION OF INTEREST: LIPID PRODUCTION IN YEAST Figure based upon J. Nielsen. FEBS Letters 583 (2009) 3905-3913
INTEGRATING KNOWLEDGE FROM BASIC AND APPLIED SCIENCES FOR A MISSION Nanobiotechnology Microbial Processes Plant Molecular Biology Microbial Molecular Biology Plant Based Resources Ecological Processes Biofuels & Industrial Chemical Systems Enzymatic Processes System Biology
MAJOR SUBSYSTEMS OF SUSTAINABLE AGRICULTURAL BASED ENERGY SYSTEM BIOMASS PRODUCTION FEEDSTOCK LOGISTICS CONVERSION TECHNOLOG Y
STATE-OF-THE-ART RESEARCH FACILITIES
The Nature of Technology Evolution All technology are combination of elements, These elements themselves are technology, and Technologies use phenomena to some purpose. W. Brian Arthur The Nature of Technology: What it is and How it Evolves, 2009
CLOSING THOUGHT The more there is to invent with, the greater will be the number of inventions. William Ogburn Social Change, 1922