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Co-firing high sulfur coal with refuse derived fuels. Technical progress report No. 5, [October--December 1995]

Description: Studies involving the tubular furnace are in the process of identifying the ideal experimental coal-to-refuse derived fuel(RDF) ratio for use in the AFBC system. A series of experiments with this furnace has been performed to determine the possible chemical pathway for formation of chlorinated organic compounds during the combustion of various RDF sources. Phenol and chlorine appear to be likely reactants necessary for the formation of these compounds. The main goal of these experiment is to determine the exact experimental conditions for the formation of chlorinated organic compounds, as well as methods to inhibit their development. Work on the fluidized bed combustor has involved five combustion runs, in which a combustion efficiency of greater than 96% and with a consistent CO{sub 2} concentration of approximately 13% was obtained. Modifications responsible for these improvements include the addition of the underbed fuel feed system and revision of the flue gas sampling system. New methods of determining combustion efficiency and percentage of SO{sub 2} capture using TG techniques to analyze combustion products are being developed. The current outlook using this TGA/FTIR method is very promising, since previously obscured reactions are being studied. the analysis of combustion products is revealing a more complete picture of the combustion process within the AFBC system.
Date: November 30, 1995
Creator: Pan, Wei-Ping; Riley, J.T. & Lloyd, W.G.
Partner: UNT Libraries Government Documents Department

Metal-metal multiply bonded complexes of technetium. Final report

Description: The primary objective of this project was to explore and develop the area of technetium metal-metal multiple bond chemistry. At the outset of the project, examples of metal-metal multiply bonded complexes of technetium were primarily limited to those supported by halide and carboxylate ligands. As a result, we intended to significantly expand the number of complexes containing Tc-Tc multiple bonds using ligands other than carboxylates or halides. In order to achieve this goal, the results obtained from years of dirhenium research was used as a guide for the development of new technetium compounds. Our emphasis, however, was on pursuing unanticipated results and exploiting the inherent differences between technetium and rhenium in order to develop chemistry beyond that which exists for rhenium. We have focused our attention on the preparation of dinuclear complexes with ligand sets that are known to support dinuclear metal-metal bonded cores in a variety of different metal oxidation states. Investigation of the consequences of electron addition and removal from metal-metal bonding manifold on the structural and physical properties of such dinuclear species will provide vital information regarding the electronic structure of Tc-Tc multiply bonded compounds.
Date: March 30, 1995
Creator: Cotton, F. A. & Haefner, S. C.
Partner: UNT Libraries Government Documents Department

General Chemistry Technical Note No. 71: Hydrogen compounds of low atomic weight

Description: This report provides a compilation of Hydrogen compounds of low atomic weight. Compounds known and reported in literature are given. Cations and anions of high Hydrogen content and/or low Z are provided as are molecules which form Lewis salts. Finally, unknown compounds for which synthesis seems probable are given.
Date: March 30, 1962
Creator: Pearson, R. K.
Partner: UNT Libraries Government Documents Department

Structural characterization and comparison of iridium, platinum and gold/palladium ultra-thin film coatings for STM of biomolecules

Description: Scanning tunneling microscopy (STM) is capable of atomic resolution and is ideally suited for imaging surfaces with uniform work function. A biological sample on a conducting substrate in air does not meet this criteria and requires a conductive coating for stable and reproducible STM imaging. In this paper, the authors describe the STM and transmission electron microscopy (TEM) characterization of ultra-thin ion-beam sputtered films of iridium and cathode sputtered gold/palladium and platinum films on highly ordered pyrolytic graphite (HOPG) which were developed for use as biomolecule coatings. The goals were the development of metal coatings sufficiently thin and fine grained that 15--20 {angstrom} features of biological molecules could be resolved using STM, and the development of a substrate/coating system which would allow complementary TEM information to be obtained for films and biological molecules. The authors demonstrate in this paper that ion-beam sputtered iridium on highly ordered pyrolytic graphite (HOPG) has met both these goals. The ion-beam sputtered iridium produced a very fine grained (< 10 {angstrom}) continuous film at 5--6 {angstrom} thickness suitable for stable air STM imaging. In comparison, cathode sputtered platinum produced 16 {angstrom} grains with the thinnest continuous film at 15 {angstrom} thickness, and the sputtered gold/palladium produced 25 {angstrom} grains with the thinnest continuous film at 18 {angstrom} thickness.
Date: October 30, 1997
Creator: Sebring, R.; Arendt, P.; Imai, B.; Bradbury, E.M.; Gatewood, J.; Panitz, J. et al.
Partner: UNT Libraries Government Documents Department

Molecular catalytic coal liquid conversion. Quarterly status report, [July--September 1995]

Description: The research was focused continually on the general tasks: Task 1, molecular organometallic catalysts for hydrogenation and Task 2, organic base catalysts for arene hydrogenation and the hydrotreating of the coal liquids. With regard to Task 1, the [1,5-HDRhCl]{sub 2}/buffer catalyst system has been investigated in detail to improve its performance. In the presence of CTAB, the stability of the catalyst was improved greatly. The relationship between the turnover number of the catalyst and the reaction time was obtained. Other aromatic compounds such as toluene, n-butylbenzene, tetralin, o-xylene all can be hydrogenated into the corresponding substituted cyclohexane derivatives in more than 94% yields when catalyzed by [1,5- HDRhCl]{sub 2} in the presence of small amount of surfactant molecules. The optimum catalyst system has been applied for the hydrogenation of tetralin in the presence of a coal liquid derived from the coal liquefaction. It was found that about 80-85% of tetralin in the mixture was hydrogenated to decalin under the conditions of these experiments. Task 2 was continually focused on the hydrogenation of coal liquids. Institution of dideuterium for dihydrogen in the hydrotreating of coal liquid at 250 {degrees}C and 1000 psig of dideuterium yielded a product that was characterized by {sup 2}H NMR. Two groups of deuteron located in the region of 6.5-8.0 ppm and 1.0-3.5 ppm, respectively, were observed. The former group was assigned to the deuterons on carbon atoms on aromatic rings and the latter to the deuterons linked to the aliphatic carbon atoms. In addition, naphthalene was hydrogenated completely to tetralin in the presence of the coal liquid under the same conditions, implying that the reduction of multiaromatic compounds was not adversely influenced by the existence of the coal liquid which contains potential catalysts poisons such as sulfur, nitrogen and oxygen.
Date: September 30, 1995
Creator: Stock, L.M. & Yang, Shiyong
Partner: UNT Libraries Government Documents Department

Vitrification of cesium-loaded crystalline silicotitanate (CST) in the shielded cells melter

Description: Through the Tanks Focus Area, the Savannah River Technology Center (SRTC) and the Oak Ridge National Laboratory participated in a joint project in which supernate waste from the Melton Valley Storage Tanks at Oak Ridge was treated by passage through a crystalline silicotitanate (CST) ion exchange column. CST was designed to sorb Cs- 137, Sr-90 and several other radionuclides from highly alkaline solutions containing large quantities of sodium.2 After demonstrating the effectiveness of CST as an ion exchange medium, ORNL shipped some of the loaded sorbent to SRTC where it was mixed with glass formers and processed in a joule-heated melter within the SRTC Shielded Cells. This report details the results of the melter run, along with the preparations that were required to complete the campaign.
Date: September 30, 1997
Creator: Andrews, M. K.; Fellinger, T. L.; Ferrara, D. M.; Harbour, J. R. & Herman, D. T.
Partner: UNT Libraries Government Documents Department

Evaluating Defoaming Agents for the Stripping Columns at the In-Tank Precipitation Facility

Description: The In-Tank Precipitation (ITP) process will concentrate the Tank 48 contents to approximately 10 wt. percent tetraphenylborate solids by filtration. The filtrate produced during the process flows to the ITP stripping columns where the soluble benzene is removed from the solution. It has been observed that a large pressure differential occurs across the column packing when the filtrate is processed in the column. One potential explanation for the pressure differential is that the filtrate is foaming in the column. Small scale stripping tests have verified that the salt solution foams. Waste Management requested assistance from SRTC in solving the foaming problem through technical task requests HLE-TTR-93013A/B (Benzene Stripper Performance Evaluation) and HLE-TTR-93044 (Kinetics of Benzene and Dissolution). Various tests were completed to determine an effective defoaming agent for use in the stripping columns. This document discusses the tests and the conclusions.
Date: June 30, 1993
Creator: McGlynn, J.F.
Partner: UNT Libraries Government Documents Department

Electrolytic regeneration of acid cupric chloride printed circuit board etchant. Quarterly report No. 4, April 30, 1996--July 30, 1996

Description: Tests on T&G Corp. proton selective membranes showed significant ion migration, so no membrane is yet on hand that will allow demonstration of oxygen ingress compensation with the pre-prototype scale regenerator. T&G is remaking a 14118 membrane, the membrane type that was used in successful bench scale testing several years ago. Modifications for pressurized operation of the pre-prototype scale plating cell were successful; the unit can withstand 8 psig pressure without leaking.
Date: August 30, 1996
Creator: Oxley, J.E. & Smialek, R.J.
Partner: UNT Libraries Government Documents Department

Recent advances in the chemical conversion of energetic materials to higher value products

Description: The objective of this program is to develop novel R3 (Resource Recovery and Recycling) alternatives to the open burning/open denotation (OB/OD) of surplus energetic materials higher value products potentially provides environmentally sound and cost- effective alternatives to OB/OD. Our recent studies on the conversion of surplus energetic materials (high explosives, propellants). The use of energetic materials as chemical feedstocks for higher value products potentially provides environmentally sound and cost-effective alternatives to OB/OD. Our recent studies on the conversion of surplus energetic materials to higher value products will be described.
Date: April 30, 1998
Creator: Mitchell, A. R., LLNL
Partner: UNT Libraries Government Documents Department

Diffuse reflectance mid-infrared spectroscopy as a tool for the identification of surface contamination on sandblasted metals

Description: The SOC 400 Surface Inspection Machine/Infrared (SIMIR) is a small, ruggedized Fourier transform infrared spectrometer having dedicated diffuse reflectance optics. The SOC 400 was designed for the purpose of detecting (qualitatively and quantitatively) oil stains on the inside surface of solid rocket motor casings in the as-sandblasted and cleaned condition at levels approaching 1 mg ft{sup {minus}2}. The performance of this instrument is described using spectral mapping techniques.
Date: July 30, 1996
Creator: Powell, G.L.; Barber, T.E.; Neu, J.T. & Nerren, B.H.
Partner: UNT Libraries Government Documents Department

Ion exchange separation of plutonium and gallium (1) resource and inventory requirements, (2) waste, emissions, and effluent, and (3) facility size

Description: The following report summarizes an effort intended to estimate within an order-of-magnitude the (1) resource and inventory requirements, (2) waste, emissions, and effluent amounts, and (3) facility size, for ion exchange (IX) separation of plutonium and gallium. This analysis is based upon processing 3.5 MT-Pu/yr. The technical basis for this summary is detailed in a separate document, {open_quotes}Preconceptual Design for Separation of Plutonium and Gallium by Ion Exchange{close_quotes}. The material balances of this separate document are based strictly on stoichiometric amounts rather than details of actual operating experience, in order to avoid classification as Unclassified Controlled Nuclear Information. This approximation neglets the thermodynamics and kinetics which can significantly impact the amount of reagents required. Consequently, the material resource requirements and waste amounts presented here would normally be considered minimums for processing 3.5 MT-Pu/yr; however, the author has compared the inventory estimates presented with that of an actual operating facility and found them similar. Additionally, the facility floor space presented here is based upon actual plutonium processing systems and can be considered a nominal estimate.
Date: September 30, 1997
Creator: DeMuth, S.
Partner: UNT Libraries Government Documents Department

Development of Vanadium-Phosphate Catalysts for Methanol Production by Selective Oxidation of Methane.

Description: This document is the seventeenth quarterly technical progress report under Contract No. DE-AC22-92PC92110 `Development of Vanadium- Phosphate Catalysts for Methanol Production by Selective Oxidation of Methane` and covers the period April-June, 1997. Vanadium phosphate, vanadyl pyrophosphate specifically, is used commercially to oxidize butane to maleic anhydride and is one of the few examples of an active and selective oxidation catalyst for alkanes. In this project we are examining this catalyst for the methane oxidation reaction. Initial process variable and kinetic studies indicated that vanadyl pyrophosphate is a reasonably active catalyst below 500{degrees}C but produces CO as the primary product, no formaldehyde or methanol were observed. A number of approaches for modification of the catalyst to improve selectivity have been tried. Results obtained earlier in this project are summarized under Project Description in the body of this report. Iron phosphate and iron phosphate supported on silica catalysts have been shown in our previous work to produce much higher yields of partial oxidation products from methane than VPO. During this quarter we have expanded these studies dramatically by detailed testing of a new silica support, by performance of detailed kinetic and product selectivity studies on the quartz form of FePO{sub 4}, both unsupported and supported on silica, by testing of a mixed valence iron phosphate Fe{sub 4}(P{sub 2}0{sub 7}), and by detailed characterization of and other materials by a number of methods including Moessbauer spectroscopy. The most selective catalyst examined to date is FePO{sub 4} supported on silica. This material has produced formaldehyde with space time yields of nearly 500 g/kg-h. Methanol yields are low but quantifiable at roughly 10 g/kg-h. Interestingly, addition of water to the feed gas produces large improvements in the formaldehyde yield by suppression of the parallel reaction to form carbon dioxide. Increasing oxygen partial pressure over this ...
Date: July 30, 1997
Creator: McCormick, R. L. & Alptekin, G. O.
Partner: UNT Libraries Government Documents Department

Hanford phosphate precipitation filtration process evaluation

Description: The purpose of this filter study was to evaluate cross-flow filtration as effective solid-liquid separation technology for treating Hanford wastes, outline operating conditions for equipment, examine the expected filter flow rates, and determine proper cleaning. A proposed Hanford waste pre-treatment process uses sodium hydroxide at high temperature to remove aluminum from sludge. This process also dissolves phosphates. Upon cooling to 40 degrees centigrade the phosphates form a Na7(PO4)2F9H2O precipitate which must be removed prior to further treatment. Filter studies were conducted with a phosphate slurry simulant to evaluate whether 0.5 micron cross-flow sintered metal Mott filters can separate the phosphate precipitate from the wash solutions. The simulant was recirculated through the filters at room temperature and filtration performance data was collected.
Date: September 30, 1997
Creator: Walker, B.W. & McCabe, D.J.
Partner: UNT Libraries Government Documents Department

Decomposition of triphenylborane with enhanced comprehensive catalyst under aerated and inert conditions

Description: This work investigated the decomposition of triphenylborane in a statistically-designed set of tests to determine the effects of four process variables: temperature, hydroxide concentration, catalyst concentration, and atmosphere. Analysis of these tests provide the following conclusions:(1) The presence of tetraphenylborate solids facilitate a 10X increase in the rate of decomposition of triphenylborane, (2) The presence of oxygen slows the decomposition of triphenylborane, (3) The activation energy of the decomposition reaction in the presence of oxygen (59.88 + 27.73 kJ/mol) is statistically lower than inerted systems (99.11 + 10.14 kJ/mol), (4) Rate constants derived from the nitrogen inerted tests encompass the rate constants from previous tests with slurries. These rate constants agree reasonably with similar values obtained from Tank 48H operations at ambient temperatures, and (5) For test conducted in air, the decomposition reaction rate constant correlated with the catalyst concentration. In tests inerted by nitrogen, the same correlation did not hold.
Date: September 30, 1997
Creator: Wilmarth, W.R.; Crawford, C.L.; Peterson, R.A. & White, T.L.
Partner: UNT Libraries Government Documents Department

Ultraviolet-visible-near infrared spectra of 50 samples

Description: Under the subject contract, Unidynamics/Phoenix recorded the ultraviolet-visible-near infrared spectra of 50 samples supplied by LANL. A Varian Cary 2300 series spectrophotometer produced the spectral data. The spectrophotometer was interfaced to a Varian D5-15 Data Station, and hard copies of data were made. Baseline corrections throughout the wavelength range were established using Halon as a reference material. Corrected measurements were automatically made by the system on every sample. Two types of sample holders were tried. Before collecting data on the LANL samples, identical samples of PETN were examined using both holders.
Date: August 30, 1988
Creator: Taylor, B.
Partner: UNT Libraries Government Documents Department

Toward a Molecular-Based Understanding of High-Temperature Solvation Phenomena in Aqueous Electrolyte Solutions

Description: The theoretical treatment of the solvation phenomenon of simple ions in aqueous solutions has been rather difficult, despite the apparent simplicity of the system. Long-range solvent-screened electrostatic interactions, coupled to the large variation (with state conditions) of the dielectric permittivity of water, give rise to a variety of rather complex solvation phenomena including dielectric saturation, electrostriction, and ion association. Notably, ion solvation in high-temperature/pressure aqueous solutions plays a leading role in hydrothermal chemistry, such as in the natural formation of ore deposits, the corrosion in boilers and reactors, and in high-temperature microbiology. Tremendous effort has been invested in the study of hydrothermal solutions to determine their thermodynamic, transport, and spectroscopic properties with the goal of elucidating the solute-solvent and solute-solute interactions over a wide range of state conditions. It is precisely at these conditions where our understanding and predictive capabilities are most precarious, in part, as a result of the coexistence of processes with two rather different length scales, i.e., short-ranged (solvation) and long-ranged (compressibility-driven) phenomena (Chialvo and Cummings 1994a). The latter feature makes hydrothermal systems extremely challenging to model, unless we are able to isolate the (compressibility-driven) propagation of the density perturbation from the (solvation-related) finite-density perturbation phenomena (Chialvo and Cummings 1995a).
Date: October 30, 1999
Creator: Chialvo, A. A.; Cummings, P. T.; Kusalik, P. G. & Simonson, J. M.
Partner: UNT Libraries Government Documents Department

The lean oxidation of iso-octane at elevated pressures

Description: Both spark-ignition and compression-ignition engines burn large molecular-weight blended fuels, a class to which the primary reference fuels (PRF), n-heptane and iso-octane belong. In this study experiments were performed using iso-octane in a high pressure flow reactor at a temperature of 925 K, at 3, 6 and 9 atm pressure and with a fuel/air equivalence ratio of approximately 0.05. Many hydrocarbon and oxygenated hydrocarbon intermediates were identified and quantified as a function of time. These experimental results provide a strin- gent test of the low temperature chemistry portion of a kinetic model as they emphasise the importance of alkyl radical addition to molecular oxygen and internal H-atom isomerization reactions relative to alkyl radical decomposition reactions. A detailed chemical kinetic mechanism is used to simulate these experiments. We provide comparisons of model predictions with experimentally measured species profiles and describe how each species is formed as predicted by the detailed model.
Date: October 30, 1998
Creator: Chen, J S; Curran, H J & Litzinger, T A
Partner: UNT Libraries Government Documents Department

Hanford and Oak Ridge underground storage tank waste filtration process evaluation

Description: The filters tested for these applications were selected based on the ability to tolerate high radiation fields. The filters used were constructed primarily of stainless steel and can be welded. These filters were among those recommended for testing of these waste streams and the Mott filters currently installed in the SRS In-Tank Precipitation facility.
Date: July 30, 1996
Creator: McCabe, D.J.
Partner: UNT Libraries Government Documents Department

Small business initiative -- Surface inspection machine infrared (SIMIR)

Description: This Cooperative Research and Development Agreement was a one year effort to make the surface inspection machine based on diffuse reflectance infrared spectroscopy (Surface Inspection Machine-Infrared, SIMIR), being developed by Surface Optics Corporation, perform to its highest potential as a practical, portable surface inspection machine. A secondary purpose was to evaluate applications that would serve both the private and the public sector. The design function of the SIMIR is to inspect sandblasted metal surfaces for cleanliness (stains). The system is also capable of evaluating graphite-resin systems for cure and heat damage, and for measuring the effects of moisture exposure on lithium hydride, corrosion on uranium metal, and the constituents of and contamination on wood, paper, and fabrics. Surface Optics Corporation supplied LMES-Y12 with a prototype SOC-400 that was evaluated by LMES-Y12 and rebuilt by Surface Optics to achieve the desired performance. LMES-Y12 subsequently evaluated the instrument against numerous applications including determining part cleanliness at the Corpus Christi Army Depot, demonstrating the ability to detect plasticizers and other organic contaminants on metals to Pantex and LANL personnel, analyzed sandblasted metal contamination standards supplied by NASA-MSFC, and demonstrated to Lockheed Martin Tactical Aircraft, marietta, GA, for analyzing the paint applied to the F-22 Fighter. The instrument also demonstrated the analysis of yarn, fabric, and finish on the textiles.
Date: May 30, 1997
Creator: Powell, G.L. & Beecroft, M.
Partner: UNT Libraries Government Documents Department

Coal and Coal Constituent Studies by Advanced EMR Techniques.

Description: Advanced electronic magnetic resonance (EMR) methods are used to examine properties of coals, chars, and molecular species related to constituents of coal. During this grant period, progress was made on a high frequency EMR system particularly appropriate for such studies and on low-frequency dynamic nuclear polarization (DNP) to examine the interaction between fluids such as water and the surface of suspended char particles.
Date: September 30, 1997
Creator: Belford, R. L.; Clarkson, R. B.; Odintsov, B. & Ceroke, P.J.
Partner: UNT Libraries Government Documents Department