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Publication Spectroscopic Signatures of Nitrogen-Substituted Zeolites(2008-08-11) Hammond, Karl D; Dogan, Fulya; Tompsett, Geoffrey A; Conner, Wm. Curtis; Grey, Clare P; Auerbach, Scott MZeolites are important heterogeneous acid catalysts with pores the diameter of small molecules. Turning zeolites into bases would open up these unique materials to alkaline-catalyzed reactions, many of which are important in the synthesis of liquid fuels from biomass. One method of preparing alkaline zeolites is to replace some framework oxygen with nitrogen, producing an amine. Unfortunately, such replacements require a post-synthetic treatment, so the question of whether the resulting materials are intact is still open. It is, in general, difficult to characterize these new materials experimentally (since the actual structures can only be guessed), so we employ a mixture of experiment and theory to develop characterization methods suitable for nitrogen-substituted zeolites. We confirm the observation that high-temperature treatment produces new peaks in the silicon NMR spectrum, and present calculations suggesting that these new peaks correspond to framework substitutions. This suggests the possibility of using a zeolitic catalyst in base-catalyzed reactions.Publication Evaluation of Acid and Enzymatic Hydrolysis of Hemicellulose Extracts Produced from Northeast Hardwood(2008-10-01) Um, Byung-HwanAt the University of Maine, a hemicellulose pre-extraction technology is now being investigated to improve pulp yields, reduce organic and inorganic load for liquor recovery, and create a feed stream for the generation of new biomaterials. In this study, we investigate 1. the extent of hemicellulose recovery by pre-extraction using green liquor pretreatment and 2. characterize the hydrolysis of the extract with respect to variable concentration via evaporation and comparing acid and enzymatic hydrolysis.Publication Validation of a Saccharomyces cerevisiae Dynamic Flux Balance Model(2008-10-01) Hjersted, Jared L; Henson, Michael APublication A novel biocatalyst for Cellulosic Ethanol Production(2008-09-19) Leschine, SusanPublication Fueling the Commercializationof Cellulosic Ethanol(2008-09-19) Howe, JohnPublication BioEnergy International, LLC. a Biorefinery Company(2008-09-19) Young, CorinnePublication The Institute for Massachusetts Biofuels Research - TIMBR(2008-09-19) Schnell, DannyEnabling the emerging biofuels industry through: -Research -Innovation -Workforce development -Industrial outreachPublication Uncertainty, climate change, and biofuels(2008-09-24) Baker, ErinPublication Biochar: A Carbon Negative Model for UMass Amherst(2008-09-19) Hale, Susanne E.Biochar is a charcoal by-product of pyrolysis production of biofuels from biomass, which offers the potential for long-term, affordable carbon sequestration. Biochar in Amazonian soils have been found to be stable in the soil for hundreds to thousands of years. New pyrolysis technologies currently being developed may have the potential to be used in the future with the new UMass co-generation Central Heating Plant to produce syngas for powering plant turbines, while at the same time producing biochar for carbon sequestration, yielding a carbon negative system. Other benefits of biochar include increased soil fertility and crop yield, stimulation of the soil microbial community and mycorrhizae, prevention of soil release of NO2 and CH4 (potent greenhouse gases), and, according to one study, the potential to reduce greenhouse gases by 10% or more worldwide.Publication Measuring and Predicting Reaction Kinetics for Clean Use of Biofuels(2008-09-19) Westmoreland, Phillip R; Labbe, Nicole J.; Li, Wenjun; Pereverzev, AndreyFuels from renewable biomass already make up part of our energy picture, and that must surely increase. However, relative to petroleum-based fuels, they are thought to generate increased aldehyde and NOx pollutants due to their high content of oxygen and sometimes nitrogen. We are working to explore, explain, and help solve these challenges. Our two major directions are measuring kinetics with flame molecular-beam mass spectrometry (MBMS) and predicting kinetics using theory, computational quantum chemistry, and our new Reactive Molecular Dynamics methods. We recently built a pioneering MBMS apparatus based on synchrotron VUV-photoionization [Taatjes et al., Science, 308, 1887 (2005)] and have used it to study flames of hydrocarbons, alcohols, aldehydes, ketones, esters, and most recently morpholine. From the data, we have predicted and inferred reaction pathways and the key elementary-reaction kinetics. Another useful approach is using our Reactive Molecular Dynamics algorithm and RMDff force field, developed for my group's polymer research. This new molecular-simulation method promises to yield powerful, quantitative insights into reactions that convert biomass into fuels, as it has for polymer decomposition. We hope to make the method still more accurate by computing energies with a new, rapid, electronic-structure-based method we have termed BEBOP (bond energies from bond-order populations). When implemented on parallel supercomputers, these methods will open the door to computational experiments for obtaining many types of reaction kinetics.Publication First Annual Conference on Cellulosic Biofuels - PROGRAM(2008-09-19) Walker, LorenPublication The Clean Energy Biofuels Act of 2008: Promoting Advanced Biofuels in Massachusetts(2008-09-19) Breger, DwaynePublication The Advanced Biofuels Policy Environment: Framing the Debate and Laying the Foundation for Industry Expansion(2008-09-19) Schuyler, AndrewPublication Agrivida Presentation to TIMBR Conference(2008-08-19) Johnson, JeremyPublication Biofuels Research Opportunities in Thermochemical Conversion of Biomass(2008-09-19) Elliott, Douglas