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in subjects: "Tetrahydrofuran"

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Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

This report describes progress on research during the eleventh quarter of this contract dealing with applications of coal pretreatment techniques in coal/oil co-processing and direct hydroliquefaction. The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal convers… more

Date: 1991-06~

Creator: Baldwin, R. M.; Gaur, S. & Miller, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Heavy recycle solvent studies in two-stage coal liquefaction. Final technical report, September 1, 1982-December 30, 1983

The objective of this program has been to study the chemistry of the components with high boiling points in a direct coal liquefaction recycle solvent and to identify those components which lead to higher overall yields and improved product stability in the initial coal dissolution step of direct coal liquefaction processes. The major conclusions are: -454 C recycle solvent is primarily aromatic hydrocarbons (73%) and contains almost no asphaltenes; +454 C recycle solvent is primarily asphalten… more

Date: January 10, 1984

Creator: Longanbach, J. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, October 1, 1979-September 30, 1980. [Ethane Elimination]

The 1,1-reductive elimination of ethane from three cis-bis(phosphine)-dimethylpalladium complexes, L/sub 2/Pd(CH/sub 3/)/sub 2/ (L = PPh/sub 3/, PPh/sub 2/,CH/sub 3/ and L/sub 2/ = Ph/sub 2/PCH/sub 2/CH/sub 2/PPh/sub 2/), and three trans analogs (L = PPh/sub 3/, PPh/sub 2/CH/sub 3/ and L/sub 2/ = 2,11-bis(diphenylphosphinomethyl)benzo(c)phenanthrene (TRANSPHOS)) was carried out. The three cis complexes underwent reductive elimination in the presence of coordinating solvents (DMSO, DMF, and THF)… more

Date: September 1, 1980

Creator: Stille, J. K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Catalyst dispersion and activity under conditions of temperature- staged liquefaction

The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of the catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experi… more

Date: September 1, 1991

Creator: Davis, A.; Schobert, H.H.; Mitchell, G.D. & Artok, L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Synthesis of block copolymers of methyl siloxane, phenyl siloxane, vinyl siloxane, etc

Synthesis of homo poly(dimethylsiloxane) PDMS, homo poly(diphenylsiloxane PDPS, and di- and tri- block copolymers of PDMS and PDPS have been carried out by anionic living polymerization, using the following reagents: hexamethylcyclotrisiloxane, HMTS and hexaphenylcyclotrisiloxane, HPTS (monomers), n-BuLi and dilithium diphenyldisilanolate, DLS (initiators), DMSO and THF (promoters) and Toluene (solvent). Lithium based catalysts are used in order to minimize siloxane rearrangement (equilibration… more

Date: June 30, 1979

Creator: Ibemesi, J.A. & Meier, D.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Simple home-made sensors for potentiometric titrations. [Nitroform CH(NO/sub 2/)/sub 3/]

A sensor for potentiometric titrations was prepared by coating a spectroscopic graphite rod with a solution of poly(vinyl chloride) and dioctyphthalate in tetrahydrofuran. The reference electrode was an Ag/AgCl single-junction electrode. The sensor was used in precipitation, acid-base, compleximetric, and redox titrations. Preparation of the coated-graphite sensor is simple and rapid. Moreover, it is quite inexpensive. A limitation is its applicability in aqueous media only, because organic sol… more

Date: April 1, 1982

Creator: Selig, W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Magnetic relaxation--coal swelling, extraction, pore size

The grant activities during this period fall into four categories: (1) Completion of preparatory work, (2) Procedure refinement and actual preparation of whole coal, coal residue, coal extract and swelled coal samples for NMR studies, (3) Related studies of coal photolysis that employ materials from preliminary extractions and that examine the u.v.-visible and mass spectra of the extracts and (4) Continued investigations of the pulsed EPR characteristics of the whole coal samples that were prep… more

Date: January 1, 1991

Creator: Doetschman, D.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Gas Phase Radiolysis and Vacuum Ultraviolet Photolysis of Heterocyclic Organic Compounds. Progress Report, Feburary 1, 1979-February 1, 1980

The long-range objective of our research group is to gain a better understanding of the processes by which complex organic molecules react when they absorb large amounts of energy. This progress report describes the results of our recent work in three areas: diradicals derived from heterocyclic compounds; trimethylene diradicals from various sources; and ion-molecule reactions.

Date: January 1, 1980

Creator: Scala, A. A.; Nguyen, D.; Rourke, W. & Caputo, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Sonic and resistivity measurements on Berea sandstone containing tetrahydrofuran hydrates: a possible analogue to natural-gas-hydrate deposits. [Tetrahydrofuran hydrates]

Deposits of natural gas hydrates exist in arctic sedimentary basins and in marine sediments on continental slopes and rises. However, the physical properties of such sediments are largely unknown. In this paper, we report laboratory sonic and resistivity measurements on Berea sandstone cores saturated with a stoichiometric mixture of tetrahydrofuran (THF) and water. We used THF as the guest species rather than methane or propane gas because THF can be mixed with water to form a solution contain… more

Date: January 1, 1983

Creator: Pearson, C.; Murphy, J.; Halleck, P.; Hermes, R. & Mathews, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Synthesis and chemistry of yttrium and lanthanide metal complexes

The objective of this research project is to determine the special features of complexes of yttrium and the lanthanide metals which will allow the design and synthesis of materials with unique chemical, physical, and catalytic properties. Past studies of yttrium and lanthanide metal alkyl and hydride complexes stabilized by cyclopentadienyl co-ligands have shown that a substantial, often singular, organometallic chemistry is available via these metals. More extensive utilization of the chemical… more

Date: September 1, 1991

Creator: Evans, W. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

This report describes progress on research during the seventh quarter of this contract dealing with applications of coal pretreatment techniques in coal hydroliquefaction. The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal conversion utilizing low rank coals a… more

Date: 1990-09~

Creator: Baldwin, R. M. & Miller, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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New regents for coal desulfurization

The primary goal of this project was development and exploration of potential new desulfurization reagents for the removal of organic sulfur'' from Illinois coals by mild chemical methods. Potential new desulfurization reagents were investigated using organic sulfur compounds of the types thought to be present in coals. Reagents included low-valent metal complexes based on nickel and on iron as well as possible Single Electron Transfer reagents. Soluble coal extracts served as second generation… more

Date: January 1, 1991

Creator: Buchanan, D.H.; Kalembasa, S.; Olson, D.; Wang, S. & Warfel, L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

This report describes progress on research during the 12th and final quarter of this contract dealing with applications of coal pretreatment techniques in coal/oil co-processing and direct hydroliquefaction. The overall objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions… more

Date: 1991-09~

Creator: Baldwin, R. M.; Gaur, S. & Miller, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Coal liquefaction process streams characterization and evaluation

This is the third Quarterly Technical Progress Report under DOE Contract DE-AC22-89PC89883. Three major topics are reported: (1) Feed coals and process oils form Wilsonville Run 259 were analyzed to provide information on process performance. Run 259 was operated in the catalytic/catalytic Close-Coupled Integrated Two-Stage Liquefaction (CC-ITSL) mode with ash recycle. Feed coals were conventionally cleaned and deep cleaned coal from the Ireland Mine (Pittsburgh seam). The catalyst used in both… more

Date: July 1, 1991

Creator: Robbins, G. A.; Brandes, S. D.; Winschel, R. A. & Burke, F. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Transuranic organometallics: The next generation

Neptunium and plutonium metal react cleanly with 3/2 equiv. I{sub 2} in aprotic ligating solvents, L, such as tetrahydrofuran (THF), pyridine (Py), and dimethylsulfoxide (DMSO) to give the triiodide complexes as tetrasolvates, AnI{sub 3}(L){sub 4} (An = Np, L = THF (1)); An = Pu, L = THF (2a), Py (2b), and DMSO (2c). These triiodide complexes are convenient precursors to new transuranic compounds. Reaction of the triiodide complexes 1 and 2a hexane with 3 equiv. of sodium bis(trimethylsilyl)ami… more

Date: January 1, 1990

Creator: Zwick, Bill D.; Sattelberger, Alfred P. & Avens, Larry R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Coal liquefaction process streams characterization and evaluation

This study demonstrated the feasibility of using temperature-programmed electron spin resonance (ESR) and thermogravimetric analysis (TGA) for the examination of tetrahydrofuran (THF)-soluble distillation resid materials derived from direct coal liquefaction. TGA is used to quantitate volatile losses in a temperature-programmed experiment. The TGA data are used to correct the free radical densities obtained by ESR as volatile material is evolved from the samples in the temperature-programmed ES… more

Date: October 1, 1992

Creator: Ibrahim, M.M. & Seehra, M.S. (West Virginia Univ., Morgantown, WV (United States). Dept. of Physics)

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Synthesis and reactivity of ultra-fine coal liquefaction catalysts

The Pacific Northwest Laboratory is currently developing ultra-fine iron-based coal liquefaction catalysts using two new particle production technologies: (1) modified reverse micelles (MRM) and (2) rapid thermal decomposition of solutes (RTDS). These methodologies have been shown to allow control over both particle size (from 1 nm to 60 nm) and composition when used to produce ultra-fine iron-based materials. Powders produced using these methods are found to be selective catalysts for carbon-c… more

Date: October 1, 1992

Creator: Linehan, J. C.; Matson, D. W.; Fulton, J. L.; Bean, R. M. & Darab, J. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Comparison of the activities of fine-particle size catalysts

The objectives of Sandia`s fine-particle size catalyst testing project are to evaluate and compare the activities of the fine-particle size catalysts being developed in DOE/PETCs Advanced Research Coal Liquefaction Program by using standard coal liquefaction test procedures. The standard procedures use Blind Canyon coal, phenanthrene as the reaction solvent, and a factorial experimental design with temperatures from 350{degrees}C to 400{degrees}C, reaction times from 20 to 60 minutes, and catal… more

Date: December 31, 1994

Creator: Stohl, F. V.; Diegert, K. V. & Goodnow, D. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Preconversion processing of bituminous coals: New directions to improved direct catalytic coal liquefaction. [Effect of preconversion heat soak with coal liquids]

A study of the high-temperature soaking started in this quarter, following the installation of reactors in the previous quarter. Two high-volatile bituminous coals and three coal liquids, which were identified in the previous report, were used. A cross-linked, three-dimensional macromolecular model has been widely accepted f or the structure of coal, but there is no direct evidence to prove this model. The conventional coal structure model has been recently re-examined by this investigator beca… more

Date: July 1, 1992

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Catalyst dispersion and activity under conditions of temperature- staged liquefaction. [Catalyst precursors for molybdenum-based catalyst and iron-based catalyst]

Two coals, a Texas subbituminous C and a Utah high volatile A bituminous, were used to examine the effects of solvent swelling and catalyst impregnation on liquefaction conversion behavior in temperature staged reactions for 30 minutes each at 275{degree} and 425{degree}C in H{sub 2} and 95:5 H{sub 2}:H{sub 2}S atmospheres. Methanol, pyridine, tetrahydrofuran, and tetrabutylammonium hydroxide were used as swelling agents. Molybdenum-based catalyst precursors were ammonium tetrathiomolybdate, mo… more

Date: July 1, 1992

Creator: Davis, A.; Schobert, H. H.; Mitchell, G. D. & Artok, L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Cobalt dicarbollide containing polymer resins for cesium and strontium uptake

Cobalt(III) dicarbollide [(C{sub 2}B{sub 9}H{sub 11}){sub 2}Co]{sup {minus}} (CB{sub 2}) is being investigated for Cs and Sr extraction from nuclear waste. Because organic solvents should be avoided, bonding of CB{sub 2} to resins were investigated. CB{sub 2} was successfully covalently bonded to polystyrene and polybenzimidazole resins. Tetrahydrofuran was the most efficient solvent for grafting. Analysis is being performed, and separation coefficients are also being determined. 3 figs, 8 refs. more

Date: April 1, 1994

Creator: Steckle, W. P. Jr.; Duke, J. R. Jr. & Jorgensen, B. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A new family of anion receptors and their effects on ion pair dissociation and conductivity of lithium salts in non-aqueous solutions

A new family of anion receptors based on aza-ether compounds have been synthesized. Since the anion complexation of these compounds is not based on either positively charged sites or hydrogen bonding, they have a potential to be used in lithium batteries as electrolyte additives. When these compounds are added into nonaqueous electrolytes using lithium salts, such as LiCl/BF or LiBr/THF, the ionic conductivity can be dramatically increased. Near Edge X-ray Absorption Fine Structure (NF-XAFS) sp… more

Date: August 1, 1994

Creator: Lee, H. S.; Yang, X. Q.; McBreen, J. & Okamoto, Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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New water soluble phosphonate and polycarboxylate complexants for enhanced f element separations

While lipophilic extractant molecules and ion exchange polymeric materials are clearly essential to efficient separation of metal ions by solvent extraction or ion exchange, the most difficult separations often could not be accomplished without the use of water soluble complexants. This report focuses on recent developments in design, synthesis and characterization of phosphonic acid and polycarboxylic acid ligands for enhanced f element separations. Emphasis is on the basic solution chemistry … more

Date: August 1, 1994

Creator: Nash, K. L.; Rickert, P. G.; Lessmann, E. P.; Mendoza, M. D.; Feil, J. F. & Sullivan, J. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Europium(III) interaction with a water-soluble extractant: From speciation to photodestruction

The first spectroscopic study of metal ion-THFTCA (tetrahydrofuran-1, 2,3,4-tetracarboxylic acid) coordination is reported. Luminescence studies provide evidence for predominance of a complex containing 1 Eu(+3) ion and 2 THFTCA molecules in aqueous processing nuclear waste. Evidence that THFTCA coordinates, at least in part, via carboxylate groups was found in the Eu(3+) {sup 5}D{sub 1} state fluorescence decay rates. Direct photochemical destruction of THFTCA was demonstrated in the study of … more

Date: August 1, 1994

Creator: Beitz, J. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department