Final technical report. Bimetallic complexes as methanol oxidation catalysts (open access)

Final technical report. Bimetallic complexes as methanol oxidation catalysts

Our work on the electrocatalyzed oxidation of methanol was initially motivated by the interest in methanol as an anodic reactant in fuel cells. The literature on electrochemical oxidation of alcohols can be roughly grouped into two sets: fuel cell studies and inorganic chemistry studies. Work on fuel cells primarily focuses on surface-catalyzed oxidation at bulk metal anodes, usually Pt or Pt/Ru alloys. In the surface science/electrochemistry approach to these studies, single molecule catalysts are generally not considered. In contrast, the inorganic community investigates the electrooxidation of alcohols in homogeneous systems. Ruthenium complexes have been the most common catalysts in these studies. The alcohol substrates are typically either secondary alcohols (e.g., isopropanol) such that the reaction stops after 2 e{sup -} oxidation to the aldehyde and 4 e{sup -} oxidation to the carboxylic acid can be observed. Methanol, which can also undergo 6 e{sup -} oxidation to CO{sub 2}, rarely appears in the homogeneous catalysis studies. Surface studies have shown that two types of metal centers with different functions result in more effective catalysts than a single metal; however, application of this concept to homogeneous systems has not been demonstrated. The major thrust of the work is to apply this insight …
Date: January 21, 2002
Creator: McElwee-White, Lisa
Object Type: Report
System: The UNT Digital Library
Strategic Research: In-Tank Generation of Corrosion Inhibitors (open access)

Strategic Research: In-Tank Generation of Corrosion Inhibitors

Prevention of stress corrosion cracking and pitting corrosion in high-level waste (HLW) tanks requires the periodic addition of corrosion inhibitors, sodium hydroxide and sodium nitrite. These inhibitor ions can be generated electrochemically from the nitrate present in the waste. Thus, a continuously operated electrochemical reactor placed in the top of the tank could generate nitrite and hydroxide. In-tank generation would eliminate the need to continually add process chemicals resulting in cost savings associated with the procurement, pretreatment and disposal of these chemicals. Experiments examined whether both nitrite and hydroxide could be generated simultaneously from a simple waste simulant in a single electrolytic cell. Results indicated that hydroxide, but not nitrite, formed at a rate that would be effective for in-tank generation. Nitrate reduction proceeded beyond the production of nitrite to produce other nitrogen-containing products. We recommend additional testing to identify an optimum cathode material for nitrite production. Alternatively, the in-tank generator may feature a divided cell configuration or dual electrochemical cells in which one cell generates hydroxide and the second cell generates nitrite.
Date: August 21, 2002
Creator: Hobbs, D. T.
Object Type: Report
System: The UNT Digital Library
Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico, Class III (open access)

Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico, Class III

The overall objective of this project is to demonstrate that a development program based on advanced reservoir management methods can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan includes developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals are (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the U.S. oil and gas industry.
Date: February 21, 2002
Creator: Murphy, Michael B.
Object Type: Report
System: The UNT Digital Library
Measurements and Models for Hazardous chemical and Mixed Wastes (open access)

Measurements and Models for Hazardous chemical and Mixed Wastes

Mixed solvent aqueous waste of various chemical compositions constitutes a significant fraction of the total waste produced by industry in the United States. Not only does the chemical process industry create large quantities of aqueous waste, but the majority of the waste inventory at the DOE sites previously used for nuclear weapons production is mixed solvent aqueous waste. In addition, large quantities of waste are expected to be generated in the clean-up of those sites. In order to effectively treat, safely handle, and properly dispose of these wastes, accurate and comprehensive knowledge of basic thermophysical properties is essential. The goal of this work is to develop a phase equilibrium model for mixed solvent aqueous solutions containing salts. An equation of state was sought for these mixtures that (a) would require a minimum of adjustable parameters and (b) could be obtained from a available data or data that were easily measured. A model was developed to predict vapor composition and pressure given the liquid composition and temperature. It is based on the Peng-Robinson equation of state, adapted to include non-volatile and salt components. The model itself is capable of predicting the vapor-liquid equilibria of a wide variety of systems composed of …
Date: August 21, 2002
Creator: Watts, Laurel A.; Holcomb, Cynthia D.; Outcalt, Stephanie L.; Louie, Beverly; Mullins, Michael E. & Rogers, Tony N.
Object Type: Report
System: The UNT Digital Library
Process Options Description for Vitrification Flowsheet Model of INEEL Sodium Bearing Waste (open access)

Process Options Description for Vitrification Flowsheet Model of INEEL Sodium Bearing Waste

The technical information required for the development of a basic steady-state process simulation of the vitrification treatment train of sodium bearing waste (SBW) at Idaho National Engineering and Environmental Laboratory (INEEL) is presented. The objective of the modeling effort is to provide the predictive capability required to optimize an entire treatment train and assess system-wide impacts of local changes at individual unit operations, with the aim of reducing the schedule and cost of future process/facility design efforts. All the information required a priori for engineers to construct and link unit operation modules in a commercial software simulator to represent the alternative treatment trains is presented. The information is of a mid- to high-level nature and consists of the following: (1) a description of twenty-four specific unit operations--their operating conditions and constraints, primary species and key outputs, and the initial modeling approaches that will be used in the first year of the simulation's development; (2) three potential configurations of the unit operations (trains) and their interdependencies via stream connections; and (3) representative stream compositional makeups.
Date: February 21, 2002
Creator: Nichols, T. T.; Taylor, D. D.; Lauerhass, L. & Barnes, C. M.
Object Type: Report
System: The UNT Digital Library
Ceramic waste form production and development at ANL-West. (open access)

Ceramic waste form production and development at ANL-West.

Argonne National Laboratory has developed a method to stabilize spent electrolyte salt discarded from electrorefiners (ER) used to treat spent nuclear fuel. The salt is stabilized in a ceramic using a pressureless consolidation technique. The starting material is zeolite 4A which is used as the host for the fission product and actinide rich salt. Glass frit is added to the salt loaded zeolite before processing to act as a binder. The zeolite 4A is converted to sodalite during processing via pressureless consolidation. This process differs from one used in the past that employed a hot isostatic press. Ceramic is created at 925 C and atmospheric pressure instead of the high pressures used in hot isostatic pressing. Process flow sheets, off-gas test results, processing equipment, and leech test results are presented.
Date: August 21, 2002
Creator: Battisti, T. J.; Goff, K. M.; Bateman, K. J.; Simpson, M. F. & Lind, J. P.
Object Type: Article
System: The UNT Digital Library
Demonstration of Caustic-Side Solvent Extraction with Optimized Solvent in the 2-cm Centrifugal Contactor Apparatus Using Dissolved Salt Cake from Tank 37H (open access)

Demonstration of Caustic-Side Solvent Extraction with Optimized Solvent in the 2-cm Centrifugal Contactor Apparatus Using Dissolved Salt Cake from Tank 37H

A solvent extraction process for removal of cesium from alkaline solutions has been developed utilizing a novel solvent invented at the Oak Ridge National Laboratory (ORNL). This solvent consists of a calix[4]arene-crown-6 extractant (BOBCalix) dissolved in an inert hydrocarbon matrix (Isopar(R) L). An alkylphenoxy alcohol modifier added to the solvent enhances the extraction power of the calixarene and prevents the formation of a third phase. An additional additive, trioctylamine (TOA), improves stripping performance and mitigates the effects of any surfactants present in the feed stream. The solvent extraction process was successfully demonstrated with actual SRS HLW supernate during testing performed at SRTC in FY-2001. However, the solvent system has recently been optimized to enhance extractant solubility in the diluent and increase suppressor concentration. The results of the optimized solvent performance in tests using the same SRS composite waste supernate as was used FY-20 01 are described in another report.
Date: October 21, 2002
Creator: Norato, M. A.
Object Type: Report
System: The UNT Digital Library
Synchrotron radiation issues in future hadron colliders (open access)

Synchrotron radiation issues in future hadron colliders

Hadron machines mostly use high field superconducting magnets operating at low temperatures. Therefore the issue of extracting a SR power heat load becomes more critical and costly. Conceptual solutions to the problem exist in the form of beam screens and photon stops. Cooled beam screens are more expensive in production and operation than photon stops, but they are, unlike photon stops, routinely used in existing machines. Photon stops are the most economical solution because the heat load is extracted at room temperature. They presently consider it most prudent to work with a combined beam screen and photon stop approach, in which the photon stop absorbs most of the SR power, and the beam screen serves only the vacuum purpose. Provided that the recently launched photon stop R and D [10] supports it, we would like to explore solutions with photon stops only. This would allow to reduce the magnet apertures to a certain extent with respect to those required to accommodate high SR power compliant beam screens and reduce cost. The possibility of magnet designs, which have larger vertical apertures where large cooling capillaries can be housed at no additional cost, would allow to soften this statement somewhat and should …
Date: November 21, 2002
Creator: Bauer, P.; Darve, C. & Terechkine, I.
Object Type: Article
System: The UNT Digital Library
Thin films and surface patterning with BEDT-TTF based charge transfer salts. (open access)

Thin films and surface patterning with BEDT-TTF based charge transfer salts.

Densely covered (ET)X{sub 2} thin films can be selectively electrodeposited on gold electrodes. The insulating (ET)X{sub 2} films are converted to (ET){sub 2}X conductive films through a novel conproportionation reaction. Both ET and ET salt patterns can be prepared with the PDMS stamping technique with use of an ET derivative with a dodecanethiol chain for surface derivatization. These solution procedures open up the possibility to prepare conductive and superconductive charge-transfer salt thin films as well as patterns.
Date: August 21, 2002
Creator: Wang, H. H.; Han, C. Y.; Noh, D.-Y.; Shin, K.-S.; Willing, G. A. & Geiser, U.
Object Type: Article
System: The UNT Digital Library
Rapidity gaps in pbar p, ep, and e+ e- collisions (open access)

Rapidity gaps in pbar p, ep, and e+ e- collisions

Results on rapidity gaps in {bar p}p collisions obtained by the CDF collaboration, in ep collisions by the ZEUS and H1 collaborations, and in e{sup +}e{sup -} collisions by the L3 collaboration are presented.
Date: October 21, 2002
Creator: Hatakeyama, K.
Object Type: Article
System: The UNT Digital Library
Polycapillary optics based neutron focusing for small sample neutron crystallography. (open access)

Polycapillary optics based neutron focusing for small sample neutron crystallography.

This work presents preliminary measurements designed to explore a new approach to neutron diffraction that is somewhat analogous to the pseudo-Laue technique, except that instead of using a broad energy (wavelength) bandwidth it uses a broad angular bandwidth. We have used a polycapillary focusing optic to focus neutrons from a monochromatic beam (using the BT-8 spectrometer on the NIST research reactor) and from a polychromatic beam at a pulsed spallation source (the Intense Pulsed Neutron Source, IPNS at Argonne National Laboratory) into a small, intense spot and have carried out preliminary diffraction measurements. Using the single crystal diffraction (SCD) facility on IPNS, diffraction of a 3{sup o} convergent beam from an alpha quartz crystal showed six diffraction beams in the 1-5{angstrom} wavelength bandwidth transmitted by the optic. The diffraction spots showed an intensity gain of 5.8 {+-} 0.9 compared to a direct beam diffracting from the same sample volume as that illuminated by the convergent beam.
Date: February 21, 2002
Creator: Gibson, W. M.; Chen-Mayer, H. H.; Mildner, D. F. R.; Prask, H. J.; Schultz, A. J.; Youngman, R. et al.
Object Type: Article
System: The UNT Digital Library