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All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Renewal of Collaborative Research: Economically Viable Forest Harvesting Practices That Increase Carbon Sequestration

Forests provide wildlife habitat, water and air purification, climate moderation, and timber and nontimber products. Concern about climate change has put forests in the limelight as sinks of atmospheric carbon. The C stored in the global vegetation, mostly in forests, is nearly equivalent to the amount present in atmospheric CO 2 . Both voluntary and government-mandated carbon trading markets are being developed and debated, some of which include C sequestration resulting from forest management as a possible tradeable commodity. However, uncertainties regarding sources of variation in sequestration rates, validation, and leakage remain significant challenges for devising strategies to include forest management in C markets. Hence, the need for scientifically-based information on C sequestration by forest management has never been greater. The consequences of forest management on the US carbon budget are large, because about two-thirds of the ≈300 million hectare US forest resource is classified as 'commercial forest.' In most C accounting budgets, forest harvesting is usually considered to cause a net release of C from the terrestrial biosphere to the atmosphere. However, forest management practices could be designed to meet the multiple goals of providing wood and paper products, creating economic returns from natural resources, while sequestering C from the atmosphere. The shelterwood harvest strategy, which removes about 30% of the basal area of the overstory trees in each of three successive harvests spread out over thirty years as part of a stand rotation of 60-100 years, may improve net C sequestration compared to clear-cutting because: (1) the average C stored on the land surface over a rotation increases, (2) harvesting only overstory trees means that a larger fraction of the harvested logs can be used for long-lived sawtimber products, compared to more pulp resulting from clearcutting, (3) the shelterwood cut encourages growth of subcanopy trees by opening up the forest canopy to increasing light penetration. Decomposition of onsite harvest slash and of wastes created during timber processing releases CO 2 to the atmosphere, thus offsetting some of the C sequestered in vegetation. Decomposition of soil C and dead roots may also be temporarily stimulated by increased light penetration and warming of the forest floor. Quantification of these processes and their net effect is needed. We began studying C sequestration in a planned shelterwood harvest at the Howland Forest in central Maine in 2000. The harvest took place in 2002 by the International Paper Corporation, who assisted us to track the fates of harvest products (Scott et al., 2004, Environmental Management 33: S9-S22). Here we present the results of intensive on-site studies of the decay of harvest slash, soil respiration, growth of the remaining trees, and net ecosystem exchange (NEE) of CO 2 during the first six years following the harvest. These results are combined with calculations of C in persisting off-site harvest products to estimate the net C consequences to date of this commercial shelterwood harvest operation. Tower-based eddy covariance is an ideal method for this study, as it integrates all C fluxes in and out of the forest over a large 'footprint' area and can reveal how the net C flux, as well as gross primary productivity and respiration, change following harvest. Because the size of this experiment precludes large-scale replication, we are use a paired-airshed approach, similar to classic large-scale paired watershed experiments. Measurements of biomass and C fluxes in control and treatment stands were compared during a pre-treatment calibration period, and then divergence from pre-treatment relationships between the two sites measured after the harvest treatment. Forests store carbon (C) as they accumulate biomass. Many forests are also commercial sources of timber and wood fiber. In most C accounting budgets, forest harvesting is usually considered to cause a net release of C from the terrestrial biosphere to the atmosphere. However, it might also be possible for commercial use of forests to contribute to terrestrial sequestration of C. The objective of the our research project is to determine whether shelterwood cutting regimes now being adopted in the commercial forests of Maine and other areas of the country can achieve these multiple goals.

09 BIOMASS FUELS↗
DOE OSTI2012

Corrosion Mechanisms in Chloride and Carbonate Salts

State of the art thermal solar power uses nitrate salts as the heat transfer fluid. In order to increase operating efficiencies high turbine inlet temperatures must be achieved. Different heat transfer fluids must be considered for this purpose. Corrosion mechanisms in chloride and carbonate based salts were reviewed to better understand the practical implications for using either salt in a solar system. Chloride salts are susceptible to high corrosion rates in the presence of moisture and oxygen. Purification techniques are extremely important to ensure good materials performance, as formation of protective layers does not readily occur. Carbonate salts form protective oxide layers, which inhibit corrosion from the base alloy. Large amounts of work have been done for molten carbonate fuel cells, but different atmospheric conditions and temperature (>650°C) will merit investigation for solar applications.

Kruizenga, Alan Michael↗
DOE OSTI2011

A Combined Genetic, Biochemical, and Biophysical Analysis of the A 1 Phylloquinone Binding Site of Photosystem I from Green Algae

This project has resulted in the increase in our understanding of how proteins interact with and influence the properties of bound cofactors. This information is important for several reasons, including providing essential information for the re-engineering of biological molecules, such as proteins, for either improved function or entirely new ones. In particular, we have found that a molecule, such as the phylloquinone used in Photosystem I (PS1), can be made a stronger electron donor by placing it in a hydrophobic environment surrounded by negative charges. In addition, the protein is constrained in its interactions with the phylloqinone, in that it must bind the cofactor tightly, but not in such a way that would stabilize the reduced (negatively-charged) version of the molecule. We have used a combination of molecular genetics, in order to make specific mutations in the region of the phylloquinone, and an advanced form of spectroscopy capable of monitoring the transfer of electrons within PS1 using living cells as the material. This approach turned out to produce a significant savings in time and supplies, as it allowed us to focus quickly on the mutants that produced interesting effects, without having to go through laborious purification of the affected proteins. We followed up selected mutants using other spectroscopic techniques in order to gain more specialized information. In addition to the main project funded by this work, this grant supported several related side-projects that also increased our understanding about related issues.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2011

A Novel Slurry-Based Biomass Reforming Process Final Technical Report

This project was focused on developing a catalytic means of producing H2 from raw, ground biomass, such as fast growing poplar trees, willow trees, or switch grass. The use of a renewable, biomass feedstock with minimal processing can enable a carbon neutral means of producing H2 in that the carbon dioxide produced from the process can be used in the environment to produce additional biomass. For economically viable production of H2, the biomass is hydrolyzed and then reformed without any additional purification steps. Any unreacted biomass and other byproduct streams are burned to provide process energy. Thus, the development of a catalyst that can operate in the demanding corrosive environment and presence of potential poisons is vital to this approach. The concept for this project is shown in Figure 1. The initial feed is assumed to be a >5 wt% slurry of ground wood in dilute base, such as potassium carbonate (K2CO3). Base hydrolysis and reforming of the wood is carried out at high but sub-critical pressures and temperatures in the presence of a solid catalyst. A Pd alloy membrane allows the continuous removal of pure , while the retentate, including methane is used as fuel in the plant. The project showed that it is possible to economically produce H2 from woody biomass in a carbon neutral manner. Technoeconomic analyses using HYSYS and the DOE's H2A tool [1] were used to design a 2000 ton day-1 (dry basis) biomass to hydrogen plant with an efficiency of 46% to 56%, depending on the mode of operation and economic assumptions, exceeding the DOE 2012 target of 43%. The cost of producing the hydrogen from such a plant would be in the range of $1/kg H2 to $2/kg H2. By using raw biomass as a feedstock, the cost of producing hydrogen at large biomass consumption rates is more cost effective than steam reforming of hydrocarbons or biomass gasification and can achieve the overall cost goals of the DOE Fuel Cell Technologies Program. The complete conversion of wood to hydrogen, methane, and carbon dioxide was repeatedly demonstrated in batch reactors varying in size from 50 mL to 7.6 L. The different wood sources (e.g., swamp maple, poplar, and commercial wood flour) were converted in the presence of a heterogeneous catalyst and base at relatively low temperatures (e.g., 310°C) at sub-critical pressures sufficient to maintain the liquid phase. Both precious metal and base metal catalysts were found to be active for the liquid phase hydrolysis and reforming of wood. Pt-based catalysts, particularly Pt-Re, were shown to be more selective toward breaking C-C bonds, resulting in a higher selectivity to hydrogen versus methane. Ni-based catalysts were found to prefer breaking C-O bonds, favoring the production of methane. The project showed that increasing the concentration of base (base to wood ratio) in the presence of Raney Ni catalysts resulted in greater selectivity toward hydrogen but at the expense of increasing the production of undesirable organic acids from the wood, lowering the amount of wood converted to gas. It was shown that by modifying Ni-based catalysts with dopants, it was possible to reduce the base concentration while maintaining the selectivity toward hydrogen and increasing wood conversion to gas versus organic acids. The final stage of the project was the construction and testing of a demonstration unit for H2 production. This continuous flow demonstration unit consisted of wood slurry and potassium carbonate feed pump systems, two reactors for hydrolysis and reforming, and a gas-liquid separation system. The technical challenges associated with unreacted wood fines and Raney Ni catalyst retention limited the demonstration unit to using a fixed bed Raney Ni catalyst form. The lower activity of the larger particle Raney Ni in turn limited the residence time and thus the wood mass flow feed rate to 50 g min-1 for a 1 wt% wood slurry. The project demonstrated continuous H2 yields with unmodified, fixed bed Raney Ni, from 63% to 100% with corresponding H2 selectivities of 6% to 21%, for periods of several hours. The fixed bed form of the Raney Ni exhibited signs of deactivation which requires further study.

08 HYDROGEN↗
DOE OSTI2012

Zone Freezing Study for Pyrochemical Process Waste Minimization

Pyroprocessing technology is a non-aqueous separation process for treatment of used nuclear fuel. At the heart of pyroprocessing lies the electrorefiner, which electrochemically dissolves uranium from the used fuel at the anode and deposits it onto a cathode. During this operation, sodium, transuranics, and fission product chlorides accumulate in the electrolyte salt (LiCl-KCl). These contaminates change the characteristics of the salt overtime and as a result, large volumes of contaminated salt are being removed, reprocessed and stored as radioactive waste. To reduce the storage volumes and improve recycling process for cost minimization, a salt purification method called zone freezing has been proposed at Korea Atomic Energy Research Institute (KAERI).

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2012

Systems level investigation of uranium response and regulation by Caulobacter crescentus

In the past year, we have fully started this project both in terms of laboratory setup and staffing. We have outfitted a new laboratory that hosts most of the equipment needed for the project, and we hired two postdoctoral fellows (Drs. Cho and Ma) who work on the project full time. Dr. Mimi Cho received her Ph.D. in the laboratory of Dr. JoAnne Stubbe at MIT in early 2012. Her graduate work focused on the biochemistry of polyhydroxybutyrate granule formation in Ralstonia eutropha . She has expertise in protein purification and enzyme characterization, which will be useful in our biochemical studies on the putative phytase. Additionally, she has experience in both fluorescence microscopy and TEM of bacterial cells, which will help us to characterize the physiology of C. crescentus under uranium stress. Dr. Jincai Ma has a Ph.D. in environmental sciences from Rutgers University. During his graduate studies, he employed a combination of molecular genetics, chemical kinetics, and spectroscopy to elucidate the mechanisms of selenium reduction by Enterobacter cloacae . After receiving his Ph.D., he studied the persistence and survival of the food pathogen, E. coli O157:H7, in soils of leafy greens at the US Salinity Laboratory (U.C. Riverside) for his postdoctoral training. Dr. Ma’s role in the current project is to investigate the proteomics of C. crescentus in response to various stresses and to examine microbe-uranium interaction. Dr. Cho started at LLNL in March 2012 and Dr. Ma in June 2012. It should be noted that the PI, Dr. Jiao, took a 3-month maternity leave (Nov 2011- Jan 2012). As a result, the pace of the progress in the last year was not as fast as we had hoped. Nevertheless, we have begun several lines of experimental approaches towards the overall goal of our research: deciphering the mechanism of uranium (U) resistance in Caulobacter crescentus . In the past year, our research has focused on one question: what are the genes and proteins that are involved in U (and other heavy metal) resistance in C. crescentus and how do these genetic elements function to confer resistance? We have started to test several of our hypotheses through a targeted approach, in which we have focused on the roles of a putative phytase and an S-layer protein. In addition, we employed three unbiased approaches towards an understanding of the fundamental processes that underpin U resistance, including Tn-seq, proteomic profiling, and Fosmid library screening. For these studies, we have integrated bacterial culturing, genetics, biochemistry, spectroscopy, electron microscopy, and next-generation sequencing. Our major accomplishments for the first year of the ECRP are listed below, categorized by specific aims.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2013

Multitasking mesoporous nanomaterials for biorefinery applications

Mesoporous silica nanoparticles (MSNs) have attracted great interest for last two decades due to their unique and advantageous structural properties, such as high surface area, pore volume, stable mesostructure, tunable pore size and controllable particle morphology. The robust silica framework provides sites for organic modifications, making MSNs ideal platforms for adsorbents and supported organocatalysts. In addition, the pores of MSNs provide cavities/ channels for incorporation of metal and metal oxide nanoparticle catalysts. These supported metal nanoparticle catalysts benefit from confined local environments to enhance their activity and selectivity for various reactions. Biomass is considered as a sustainable feedstock with potential to replace diminishing fossil fuels for the production of biofuels. Among several strategies, one of the promising methods of biofuel production from biomass is to reduce the oxygen content of the feedstock in order to improve the energy density. This can be achieved by creating C-C bonds between biomass derived intermediates to increase the molecular weight of the final hydrocarbon molecules. In this context, pore size and organic functionality of MSNs are varied to obtain the ideal catalyst for a C-C bond forming reaction: the aldol condensation. The mechanistic aspects of this reaction in supported heterogeneous catalysts are explored. The modification of supported organocatalyst and the effect of solvent on the reaction are rationalized. The significance of two functional surfaces of MSNs is exploited by enzyme immobilization on the external surface and organo catalyst functionalization on the internal surface. Using this bifunctional catalyst, the tandem conversion of small chain alcohols into longer chain hydrocarbon molecules is demonstrated. The ability to incorporate metal and metal oxide nanoparticles in the pores and subsequent functionalization led to develop organic modified magnetic MSNs (OM-MSNs) for applications in microalgae biorefinery. Two different integrated biorefinery systems are highlighted. (i) OM-MSNs are used to harvest microalgae and selectively sequester free fatty acids (FFAs). (ii) OM-MSNs are shown to selectively sequester FFAs and convert them into diesel-range liquid hydrocarbon fuels. A similar MSN supported metal nanoparticle catalyst is demonstrated to transform FFAs into green diesel with even greater activity and selectivity. The incorporation of a different organic functional group into MSN provides a selective adsorbent for separation and purification of α-tocopherol from microalgae oil. The functional group with electron deficient aromatic rings demonstrated high sequestration capacity and selectivity of {alpha}-tocopherol.

09 BIOMASS FUELS↗
DOE OSTI2013

Research and Development for Off-Road Fuel Cell Applications U.S. Department of Energy Grant DE-FG36-04GO14303 - Final Report

Off-road concerns are related to the effects of shock and vibration and air quality on fuel cell power requirements. Mechanical stresses on differing material makeup and mass distribution within the system may render some components susceptible to impulse trauma while others may show adverse effects from harmonic disturbances or broad band mechanical agitation. One of the recognized challenges in fuel cell systems air purification is in providing a highly efficient particulate and chemical filter with minimal pressure drop. PEM integrators do not want additional parasitic loads added to the system as compensation for a highly efficient yet highly restrictive filter. Additionally, there is challenge in integrating multiple functions into a single air intake module tasked with effectively filtering high dust loads, diesel soot, pesticides, ammonias, and other anticipated off-road contaminants. This project has investigated both off-road associated issues cumulating in the prototype build and testing of two light duty off-road vehicles with integrated fuel cell power plant systems.

08 HYDROGEN↗
DOE OSTI2011

Extended Operations of the Pratt & Whitney Rocketdyne Pilot-Scale Compact Reformer: Year 6 - Activity 3.2 - Development of a National Center for Hydrogen Technology

U.S. and global demand for hydrogen is large and growing for use in the production of chemicals, materials, foods, pharmaceuticals, and fuels (including some low-carbon biofuels). Conventional hydrogen production technologies are expensive, have sizeable space requirements, and are large carbon dioxide emitters. A novel sorbent-based hydrogen production technology is being developed and advanced toward field demonstration that promises smaller size, greater efficiency, lower costs, and reduced to no net carbon dioxide emissions compared to conventional hydrogen production technology. Development efforts at the pilot scale have addressed materials compatibility, hot-gas filtration, and high-temperature solids transport and metering, among other issues, and have provided the basis for a preliminary process design with associated economics. The process was able to achieve a 93% hydrogen purity on a purge gasfree basis directly out of the pilot unit prior to downstream purification.

08 HYDROGEN↗
DOE OSTI2012

Coal Ash Behavior in Reducing Environments (CABRE) III: Year 6 - Activity 1.10 - Development of a National Center for Hydrogen

The Energy & Environmental Research Center (EERC) has been conducting research on gasification for six decades. One of the objectives of this gasification research has been to maximize carbon conversion and the water–gas shift process for optimal hydrogen production and syngas quality. This research focus and experience were a perfect fit for the National Center for Hydrogen Technology ® (NCHT®) Program at the EERC for improving all aspects of coal gasification, which ultimately aids in the production and purification of hydrogen. A consortia project was developed under the NCHT Program to develop an improved predictive model for ash formation and deposition under the project entitled “Coal Ash Behavior in Reducing Environments (CABRE) III: Development of the CABRE III Model.” The computer-based program is now applicable to the modeling of coal and ash behavior in both entrained-flow and fluidized-bed gasification systems to aid in overall gasification efficiency. This model represents a significant improvement over the CABRE II model and runs on a Microsoft Windows PC platform.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2013

Redox Interaction of Cytochromes and Bacteria with Oxide Surfaces: Probing Redox-Linked Conformation Change (Final Technical Report)

The biochemistry of bacterial proteins involved in redox transformations of metals and minerals is, without dispute, an important area of research. Nevertheless, most studies on bacterial metal transformation have focused not on biochemistry but on genetics and genomics. The objective of this research is to better understand the role of conformation change in electron transfer from cytochromes to minerals, a process that underpins respiratory metal reduction by bacteria in nature and in bioremediation strategies, including reductive immobilization of radioactive contaminants. Our DOE-funded work is specifically focused on answering long-standing questions about the biochemical behavior of these very interesting proteins, and our findings thus far have already made impacts in the fields of environmental microbiology and biogeochemistry. Among the key findings from the project are 1) Successful large-scale production of biomass for protein isolation; 2) Purification of several c-type cytochromes for biochemical study; 3) Characterization of these proteins using spectrophotometric and electrochemical techniques; 4) Examination of protein conformational change and redox activity towards metal oxides using a small mass cytochrome c from Acidiphilium cryptum; 5) Proteomic characterization of A. cryptum biofilms; 6) Training of 2 undergraduate research assistants; 7) Publications and several meeting presentations.

58 GEOSCIENCES↗
DOE OSTI2013

Age Dating of SRM U050: LLNL Results

Two solutions of U050 standard (#1 and #2) were prepared at LLNL from two separate bottles of the SRM. These solutions were analyzed for 230 Th and 234 U by the methods described in the procedures supplied previously, with some modification of the Th purification procedure that will be described in our presentation. The first step is to measure the uranium concentration and isotopic composition of the primary solutions. To accomplish this, it is necessary to prepare secondary and sometimes tertiary dilutions to lower the U concentration to a range where conservative amounts of 233 U spike can be used. One two step dilution was made in January, and a replicate independent two-step dilution was made in February 2013. The results of these U concentration measurements did not agree very well, so a third set of single-step dilutions were made, spiked, and analyzed in July 2013.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2013

An interface tracking model for droplet electrocoalescence.

This report describes an Early Career Laboratory Directed Research and Development (LDRD) project to develop an interface tracking model for droplet electrocoalescence. Many fluid-based technologies rely on electrical fields to control the motion of droplets, e.g. microfluidic devices for high-speed droplet sorting, solution separation for chemical detectors, and purification of biodiesel fuel. Precise control over droplets is crucial to these applications. However, electric fields can induce complex and unpredictable fluid dynamics. Recent experiments (Ristenpart et al. 2009) have demonstrated that oppositely charged droplets bounce rather than coalesce in the presence of strong electric fields. A transient aqueous bridge forms between approaching drops prior to pinch-off. This observation applies to many types of fluids, but neither theory nor experiments have been able to offer a satisfactory explanation. Analytic hydrodynamic approximations for interfaces become invalid near coalescence, and therefore detailed numerical simulations are necessary. This is a computationally challenging problem that involves tracking a moving interface and solving complex multi-physics and multi-scale dynamics, which are beyond the capabilities of most state-of-the-art simulations. An interface-tracking model for electro-coalescence can provide a new perspective to a variety of applications in which interfacial physics are coupled with electrodynamics, including electro-osmosis, fabrication of microelectronics, fuel atomization, oil dehydration, nuclear waste reprocessing and solution separation for chemical detectors. We present a conformal decomposition finite element (CDFEM) interface-tracking method for the electrohydrodynamics of two-phase flow to demonstrate electro-coalescence. CDFEM is a sharp interface method that decomposes elements along fluid-fluid boundaries and uses a level set function to represent the interface.

Erickson, Lindsay Crowl↗
DOE OSTI2011

Carbonate solutions for carbon capture: a summary

Potassium and sodium carbonate solutions have been studied and used for carbon capture applications since the early 20th century. They were first used to capture carbon dioxide for dry ice manufacturing, but were later supplanted by amine solutions (such as monoethanolamine, MEA) because of the faster reaction rate of amine solutions (Knuutila et al., 2009a). The use of carbonate solutions for other applications, however, has persisted to present day. In particular, the Benfield process (a.k.a the hot potassium carbonate process, or “hot pot”) is widely used for the purification of natural gas, synthesis gas (from coal gasification), town gas, and other gases (Kohl and Nielsen, 1997).

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2013

Development of Novel Method for Rapid Extract of Radionuclides from Solution using Polymer Ligand Film [Dissertation]

Accurate and fast determination of the activity of radionuclides in a sample is critical for nuclear forensics and emergency response. Radioanalytical techniques are well established for radionuclides measurement, however, they are slow and labor intensive, requiring extensive radiochemical separations and purification prior to analysis. With these limitations of current methods, there is great interest for a new technique to rapidly process samples. This dissertation describes a new analyte extraction medium called Polymer Ligand Film (PLF) developed to rapidly extract radionuclides. Polymer Ligand Film is a polymer medium with ligands incorporated in its matrix that selectively and rapidly extract analytes from a solution. The main focus of the new technique is to shorten and simplify the procedure necessary to chemically isolate radionuclides for determination by alpha spectrometry or beta counting.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2011

California GAMA Special Study: Stable isotopic composition of groundwater boron – Analytical method development

Boron is a ubiquitous dissolved constituent in natural waters due to its high solubility, natural occurrence in continental crust, and anthropogenic use in fertilizers, consumer products, and other non-natural sources. The two stable isotopes of boron, 10 B and 11 B (natural abundances ≈ 19.9 and ≈ 80.1 atom percent, respectively), undergo isotopic fractionation due to a variety of chemical processes related to boron speciation ( 10 B is preferentially incorporated into B(OH) 4 - versus B(OH) 3 , e.g. Byrne et al., 2006). The isotopic composition of dissolved boron in groundwater can be used to determine the source(s) of boron; this information can be used to infer the source(s) of other co-migrating contaminants (e.g. nitrate, pharmaceuticals, etc.). Boron behaves as a conservative element in groundwater and surface water systems (Barth, 2000), and the isotopic signature of boron is most useful in conjunction with other stable and radiogenic isotope systems (e.g. δ 18 O, δ 15 N, δ 13 C, 87 Sr/ 86 Sr; Tirez et al., 2010; Widory et al., 2004; Widory et al., 2005) to determine the source(s) of contaminants of interest. We present here a method for boron purification in natural water samples (groundwater, surface water, and seawater) by ion exchange chemistry and measurement of boron isotopic composition by MC-ICP-MS. These methods can be applied to samples with boron concentrations as low as 10 ppb with precision on δ 11 B measurements better than ± 1 ‰. We utilize boron isotopic measurements of boric acid, groundwater, and seawater standards to validate the methods. We also present boron isotopic measurements of San Diego County domestic well samples to demonstrate how these methods can be applied to any study of natural water samples.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2013

Bimetallic Nanocatalysts in Mesoporous Silica for Hydrogen Production from Coal-Derived Fuels

In steam reforming reactions (SRRs) of alkanes and alcohols to produce H 2 , noble metals such as platinum (Pt) and palladium (Pd) are extensively used as catalyst. These metals are expensive; so, to reduce noble-metal loading, bi-metallic nanocatalysts containing non-noble metals in MCM-41 (Mobil Composition of Material No. 41, a mesoporous material) as a support material with high-surface area were synthesized using one-pot hydrothermal procedure with a surfactant such as cetyltrimethylammonium bromide (CTAB) as a template. Bi-metallic nanocatalysts of Pd-Ni and Pd-Co with varying metal loadings in MCM-41 were characterized by x-ray diffraction (XRD), N 2 adsorption, and Transmission electron microscopy (TEM) techniques. The BET surface area of MCM-41 (~1000 m 2 /g) containing metal nanoparticles decreases with the increase in metal loading. The FTIR studies confirm strong interaction between Si-O-M (M = Pd, Ni, Co) units and successful inclusion of metal into the mesoporous silica matrix. The catalyst activities were examined in steam reforming of methanol (SRM) reactions to produce hydrogen. Reference tests using catalysts containing individual metals (Pd, Ni and Co) were also performed to investigate the effect of the bimetallic system on the catalytic behavior in the SRM reactions. The bimetallic system remarkably improves the hydrogen selectivity, methanol conversion and stability of the catalyst. The results are consistent with a synergistic behavior for the Pd-Ni-bimetallic system. The performance, durability and thermal stability of the Pd-Ni/MCM-41 and Pd-Co/MCM-41 suggest that these materials may be promising catalysts for hydrogen production from biofuels. A part of this work for synthesis and characterization of Pd-Ni-MCM-41 and its activity for SRM reactions has been published (“Development of Mesoporous Silica Encapsulated Pd-Ni Nanocatalyst for Hydrogen Production” in “Production and Purification of Ultraclean Transportation Fuels”; Hu, Y., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 2011.)

08 HYDROGEN↗
DOE OSTI2014

Avian Diagnostic and Therapeutic Antibodies

A number of infectious agents have the potential of causing significant clinical symptomology and even death, but despite this, the number of incidence remain below the level that supports producing a vaccine. Therapeutic antibodies provide a viable treatment option for many of these diseases. We proposed that antibodies derived from West Nile Virus (WNV) immunized geese would be able to treat WNV infection in mammals and potential humans. We demonstrated that WNV specific goose antibodies are indeed successful in treating WNV infection both prophylactically and therapeutically in a golden hamster model. We demonstrated that the goose derived antibodies are non-reactogenic, i.e. do not cause an inflammatory response with multiple exposures in mammals. We also developed both a specific pathogen free facility to house the geese during the antibody production phase and a patent-pending purification process to purify the antibodies to greater than 99% purity. Therefore, the success of these study will allow a cost effective rapidly producible therapeutic toward clinical testing with the necessary infrastructure and processes developed and in place.

60 APPLIED LIFE SCIENCES↗

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