2,190 Matching Results

Search Results

Advanced search parameters have been applied.

Sulfur Compounds in Crude Oil

Description: From Abstract: "This report summarizes a systematic 20-year study of the organic sulfur compounds in Wasson, Texas, crude oil and, to a lesser extent, of three crude oils, that culminated in some 200 individual sulfur-compound identifications. This report reviews early sulfur literature covering petroleum sulfur compound identifications completed before this study was begun, and cites 58 papers resulting from this work."
Date: unknown
Creator: Rall, H. T.; Thompson, C. J.; Coleman, H. J. & Hopkins, R. L.
Partner: UNT Libraries Government Documents Department

Contributions to the Data on Theoretical Metallurgy: [Part] 7. The Thermodynamic Properties of Sulphur and its Inorganic Compounds

Description: Report issued by the Bureau of Mines discussing the thermodynamic properties of sulfur, and its inorganic compounds. As stated in the introduction, "the present bulletin has as its primary purpose the correlation of the thermodynamic properties of elementary sulfur and its inorganic compounds and the presentation, after careful consideration of all available information, of a self-consistent system of thermodynamic relationships for these substances" (p. 1). This report includes tables.
Date: 1937
Creator: Kelley, K. K.
Partner: UNT Libraries Government Documents Department

Bioprocessing of crude oils and desulfurization using electro-spray reactors

Description: Biological removal of organic sulfur from petroleum feedstocks offers an attractive alternative to conventional thermochemical treatment due to the mild operating conditions afforded by the biocatalyst. Electro-spray bioreactors were investigated for use in desulfurization due to their reported operational cost savings relative to mechanically agitated reactors and their capability of forming emulsions < 5 {micro}m. Here, the rates dibenzothiophene (DBT) oxidation to 2-hydroxybiphenyl (2-HBP) in hexadecane, by Rhodococcus sp. IGTS8 are compared in the two reactor systems. Desulfurization rates ranged from 1.0 and 5.0 mg 2-HBP/(dry g cells-h), independent of the reactor employed. The batch stirred reactor was capable of forming a very fine emulsion in the presence of the biocatalyst IGTS8, similar to that formed in the electro-spray reactors, presumably due to the fact that the biocatalyst produces its own surfactant. While electro-spray reactors did not prove to be advantageous for the IGTS8 desulfurization system, it may prove advantageous for systems which do not produce surface-active bioagents in addition to being mass transport limited.
Date: July 1, 1998
Creator: Kaufman, E. N. & Borole, A. P.
Partner: UNT Libraries Government Documents Department

The MAP3S Aerosol Sulfate Acidity Network: A Progress Report and Data Summary, November 1981

Description: Abstract: A network of five atmospheric aerosol samplers was established in the northeastern US starting in February 1977. Size-fractionated samples of the aerosol were collected continuously with four-hour time resolution until the network was dismantled in February 1980. The aerosol-loading and aerosol-chemistry data obtained over this three-year period are summarized in this report. In particular, the samples were analyzed for the sulfate acidity of the aerosol. The acidity was found to be quite high over prolonged periods of time, with the monthly averaged acidity approaching that of ammonium bisulfate at several of the sites. Monthly, seasonal, daily, and diurnal variations in aerosol particle loading and acidity, and sulfate, ammonium, and nitrate ion concentrations are presented. The aerosol-chemistry data are tabulated separately for each of the sampling sites.
Date: November 1981
Creator: Johnson, S. A.; Kumar, R.; Cunningham, P. T. & Lang, T. A.
Partner: UNT Libraries Government Documents Department

Contributions to the Data on Theoretical Metallurgy: [Part] 7. The Thermodynamic Properties of Sulphur and its Inorganic Compounds

Description: Report issued by the Bureau of Mines over studies on the thermodynamics of sulphur. As stated in the introduction, "the present bulletin has as its primary purpose the correlation of the thermodynamic properties of elementary sulphur and its inorganic compounds and the presentation, after careful consideration of all available information, of a self-consistent system of thermodynamic relationships for these substances" (p. 1). This report includes tables.
Date: 1937
Creator: Kelley, K. K.
Partner: UNT Libraries Government Documents Department

Concentration of Plutonium by Cation Exchange--Stabilization of Pu(III) in Nitric Acid

Description: A study to define the effectiveness limits of sulfamic acid and to discover other better stabilizers for Pu(III) is described. Ascorbic and isoascorbic acids, used in conjunction with sulfamic acid reduced Pu(IV) to stable Pu(III) in nitric acid. Aminoguanidine sulfate also retarded the oxidation of Pu(III) but did not reduce Pu(IV). (J.R.D.)
Date: February 1, 1959
Creator: Tober, F. W. & Russel, E. R.
Partner: UNT Libraries Government Documents Department

Single- and multi-photon ionization studies of organosulfur species

Description: Accurate ionization energies (IE`s) for molecular species are used for prediction of chemical reactivity and are of fundamental importance to chemists. The IE of a gaseous molecule can be determined routinely in a photoionization or a photoelectron experiment. IE determinations made in conventional photoionization and photoelectron studies have uncertainties in the range of 3--100 meV (25--250 cm{sup {minus}1}). In the past decade, the most exciting development in the field of photoionization and photoelectron spectroscopy has been the availability of high resolution, tunable ultraviolet (UV) and vacuum ultraviolet (VUV) laser sources. The laser pulsed field ionization photoelectron (PFI-PE) scheme is currently the state-of-the-art photoelectron spectroscopic technique and is capable of providing photoelectron energy resolution close to the optical resolution. The author has focused attention on the photoionization processes of some sulfur-containing species. The studies of the photoionization and photodissociation on sulfur-containing compounds [such as CS{sub 2}, CH{sub 3}SH, CH{sub 3}SSCH{sub 3}, CH{sub 3}CH{sub 2}SCH{sub 2}CH{sub 3}, HSCH{sub 2}CH{sub 2}SH and C{sub 4}H{sub 4}S (thiophene) and sulfur-containing radicals, such as HS, CS, CH{sub 3}S, CH{sub 3}CH{sub 2}S and CH{sub 3}SS], have been the major subjects in the group because sulfur is an important species contributing to air pollution in the atmosphere. The modeling of the combustion and oxidation of sulfur compounds represents important steps for the control of both the production and the elimination of sulfur-containing pollutants. Chapter 1 is a general introduction of the thesis. Chapters 2 and 6 contain five papers published in, or accepted for publication in, academic periodicals. In Chapter 7, the progress of the construction in the laboratory of a new vacuum ultraviolet laser system equipped with a reflectron mass spectrometer is presented. Chapters 2 through 7 have been removed for separate processing. A general conclusion of these studies are given in Chapter 8 followed by an ...
Date: February 12, 1999
Creator: Cheung, Y.S.
Partner: UNT Libraries Government Documents Department

Development and application of thin-layer spectroelectrochemical techniques for the study of organosulfur monolayers adsorbed at gold

Description: A main research interest is the characterization of monolayers formed by the spontaneous adsorption of organosulfur compounds at gold. This dissertation describes the development and application of long optical pathlength thin-layer spectroelectrochemistry in an attempt to address key issues regarding the reactivity of surface-immobilized molecules. The first section of this introductory chapter briefly describes the general approach to the preparation and characterization of these films. The last section provides an overview of the main principles and advantages of thin-layer spectroelectrochemistry for studying surface-adsorbed species. The body of this dissertation is divided into four chapters. Chapter 2 consists of a paper describing the design, construction, and characterization of a cuvette-based LOPTLC. Chapter 3 is a paper which examines the reductive desorption process using thin-layer spectroelectrochemistry to monitor and identify the desorption product. Chapter 4 is a paper describing the characterization of monolayers functionalized with a catechol terminal group which serves as a redox transformable coordination site for metal ion binding. Chapter 5 discusses the application of thin-layer spectroelectrochemistry to acid-base reactivity studies of surface-immobilized molecules. The final section provides some general conclusions and a prospectus for future studies. These chapters have been processed separately for inclusion on the data base. This report contains the introduction, references, and general conclusions. 78 refs.
Date: October 8, 1997
Creator: Simmons, N.
Partner: UNT Libraries Government Documents Department

Low Temperature Sorbents for removal of Sulfur Compounds from fluid feed Streams

Description: A sorbent material is provided comprising a material reactive with sulfur, a binder unreactive with sulfur and an inert material, wherein the sorbent absorbs the sulfur at temperatures between 30 and 200 C. Sulfur absorption capacity as high as 22 weight percent has been observed with these materials.
Date: September 30, 1999
Creator: Siriwardane, Ranjan
Partner: UNT Libraries Government Documents Department

SULFUR REDUCTION IN GASOLINE AND DIESEL FUELS BY EXTRACTION/ADSORPTION OF REFRACTORY DIBENZOTHIOPHENES

Description: Using the classical coordination compound, Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+}, they have prepared a metal complex with a 4,6-dimenthyldibenzothiophene ligand. The compound Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} also reacts with thiophene, benzothiophene and dibenzothiophene (DBT) at room temperature. They have found that Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} removes over 50% of the DBT in simulated petroleum feedstocks by a biphasic extraction process. The extraction phase is readily generated by air-oxidation thereby completing a cyclic process that removes DBT from petroleum feedstocks.
Date: October 1, 2001
Creator: Angelici, Robert J.; McKinley, Scott G. & Alvarez, Celedonio
Partner: UNT Libraries Government Documents Department

A NOVEL APPROACH TO CATALYTIC DESULFURIZATION OF COAL

Description: The nonionic superbase P(MeNCH{sub 2}CH{sub 2}){sub 3}N (A) efficiently desulfurizes trisulfides to disulfides and monosulfides, disulfides to monosulfides, and propylene sulfide to propene. S=P(MeNCH{sub 2}CH{sub 2}){sub 3}N (B) was formed as the sulfur acceptor. P(NMe{sub 2}){sub 3} was a much poorer desulfurizing agent than A under the same reaction conditions. Thiocyanates and triphenylphosphine sulfide were also desulfurized with A, but N-(phenylthio)phthalimide formed [A-SP]{sup +} phthalimide in quantitative yield.
Date: August 31, 1998
Creator: Verkade, John G.
Partner: UNT Libraries Government Documents Department

A NOVEL APPROACH TO CATALYTIC DESULFURIZATION OF COAL

Description: The reactions of dialkyl mono- and disulfides and functionalized alkylthio compounds with sodium in refluxing hydrocarbon solvent (tetradecane, mesitylene or toluene) resulted in sulfur-free products in very high yields. Greater than 95% sulfur removal was observed when dialkyl mono or polysulfides were treated with Na in liquid ammonia. Polycyclic aromatic sulfur heterocycles were only moderately desulfurized under these conditions while phenylthio derivatives gave thiophenol as the major product and dithiophenols as the minor products.
Date: February 28, 1998
Creator: Verkade, John G.
Partner: UNT Libraries Government Documents Department

Demonstration of Mixed Waste Debris Macroencapsulation Using Sulfur Polymer Cement

Description: This report covers work performed during FY 1997 as part of the Evaluation of Sulfur Polymer Cement Fast-Track System Project. The project is in support of the ``Mercury Working Group/Mercury Treatment Demonstrations - Oak Ridge`` and is described in technical task plan (TTP) OR-16MW-61. Macroencapsulation is the treatment technology required for debris by the U.S. Environmental Protection Agency Land Disposal Restrictions (LDR) under the Resource Conservation and Recovery Act. Based upon the results of previous work performed at Oak Ridge, the concept of using sulfur polymer cement (SPC) for this purpose was submitted to the Mixed Waste Focus Area (MWFA). Because of the promising properties of the material, the MWFA accepted this Quick Win project, which was to demonstrate the feasibility of macroencapsulation of actual mixed waste debris stored on the Oak Ridge Reservation. The waste acceptance criteria from Envirocare, Utah, were chosen as a standard for the determination of the final waste form produced. During this demonstration, it was shown that SPC was a good candidate for macroencapsulation of mixed waste debris, especially when the debris pieces were dry. The matrix was found to be quite easy to use and, once the optimum operating conditions were identified, very straightforward to replicate for batch treatment. The demonstration was able to render LDR compliant more than 400 kg of mixed wastes stored at the Oak Ridge National Laboratory.
Date: July 1, 1998
Creator: Mattus, C.H.
Partner: UNT Libraries Government Documents Department

Near-field single molecule spectroscopy

Description: The high spatial resolution and sensitivity of near-field fluorescence microscopy allows one to study spectroscopic and dynamical properties of individual molecules at room temperature. Time-resolved experiments which probe the dynamical behavior of single molecules are discussed. Ground rules for applying near-field spectroscopy and the effect of the aluminum coated near-field probe on spectroscopic measurements are presented.
Date: February 1, 1995
Creator: Xie, X.S. & Dunn, R.C.
Partner: UNT Libraries Government Documents Department

Microbial stabilization of sulfur-landen sorbents; Technical report, September 1--November 30, 1993

Description: Clean coal technologies that involve limestone for sulfur capture generate lime/limestone products laden with sulfur at various oxidation states. If sulfur is completely stabilized as sulfate, the spent sorbent is ready for commercial utilization as gypsum. However, the presence of reduced sulfur species requires additional processing. Thermal oxidation of reduced sulfur can result in undesirable release of SO{sub 2}. Microbial oxidation might provide an inexpensive and effective alternative. Sorbents laden with reduced forms of sulfur such as sulfide, sulfite, or various polythionate species serve as growth substrates for sulfur-oxidizing bacteria, which have the potential to convert all sulfur to sulfate. This quarter, efforts focused on determining the combined effects of dibasic acids (DBA) and Ca{sup +2} concentration on several strains of neutrophilic thiobacilli, including Thiobacillus neapolitanus ATCC 23639 and ATCC 23641, and an isolate, TQ1, which was obtained from a commercial sulfur dioxide scrubber that utilizes DBA.
Date: December 31, 1993
Creator: Miller, K.W.
Partner: UNT Libraries Government Documents Department

Coal Supply and Air Quality Limitations on Fossil-Fueled Energy Centers

Description: The coterminous United States is screened on a county-by-county basis to identify areas most likely to provide sites for fossil energy centers (FECs) utilizing local coals and having capacities between 5,000 and 20,000 MWe. Areas eliminated as potential sites include national public lands excluded by legislation, urbanized areas, Air Quality Maintenance Areas for particulates and SO2, and counties where air quality data indicate violations of particulate or SO2 ambient standards. The remaining counties are further screened for suitable coal reserves. The quality of coal required for an FEC to meet emissions and ambient standards is determined for sulfur content and heating value. Based on Bureau of Mines coal reserve data, counties in areas with not enough quality reserves to support an FEC are eliminated. Areas most likely to provide sites for FECs of 5,000, 10,000, and 20,000 MWe, in two different spatial configurations, each with and without flue gas desulfurization are determined and mapped. The possible impacts of regulations for the prevention of significant deterioration are illustrated.
Date: 1976
Creator: Smith, Albert E.; Wolsko, Thomas D. & Cirillo, Richard R.
Partner: UNT Libraries Government Documents Department

Synthesis and Characterization of 2,3-Dichloropyrrolo[1,2-a]benzimidazol-1-one and Its Methylthiol Derivatives

Description: Condensation of 2,3-dichloromaleic anhydride and o-phenylenediamine in refluxing toluene affords the three compounds 2,3-dichloro-N-o-C6H4(NH2)maleimide (1), N,N¢-o-C6H4-bis(2,3-dichloromaleimide) (2), and 2,3-dichloropyrrolo[1,2-a]benzimidazol-1-one (3), with compound 1 as the major product. Repeating the same reaction in the presence of added PTSA furnishes compound 3 as the major product. Treatment of 3 with methylthiol in the presence of pyridine affords monosulfide compounds 2-chloro-3-methylthiopyrrolo[1,2-a]benzimidazol-1-one (4) and and the disulfide derivatives 2,3-di(methylthio)pyrrolo[1,2-a]benzimidazol-1-one (5). The substitution of the first chlorine group in compound 3 occurs regioselectively at C-3 to produce compound 4, followed by replacement of the remaining chlorine group to furnish the disulfide compounds 5. The new compounds 1-5 have been isolated by column chromatography and characterized by IR, NMR, XRD, CV and etc.
Date: May 2006
Creator: Wu, Guanmin
Partner: UNT Libraries

Replacing chemicals in recycle mills with mechanical alternatives

Description: A high-intensity spark fired underwater decomposes a small amount of the water into hydroxyl radicals, which are strong oxidants. These are able to oxidize contaminants such as glue and wood pitch that enter paper recycling mills as a part of the incoming furnish and cost the industry several hundred million dollars. The sparking technique is safe, inexpensive, and is capable of treating large volumes of water, which makes it attractive for mill applications. Several mill trials were run. Sparking caused a decrease in the tack of the deposits in one case. Lower bleach use occurred in two other mills; sparking reduced the degree of ink reattachment to fiber. The payback for either application is attractive. Sparking induced deposition of contaminants in another mill, which is a positive development--if it can be controlled. The technique is also able to degas water and to oxidize odor-causing sulfur compounds. Although one unit has been purchased by a mill, second-order effects caused by the technology needs to be defined further before the technology can be broadly applied.
Date: July 1, 2002
Creator: Technology, Institute of Paper Science
Partner: UNT Libraries Government Documents Department

Reducing Emissions of Volatile Organic Compounds - Final Report - 08/15/1997 - 02/14/2001

Description: The overall objective of this research was to determine if the shallow suspended growth reactor (SSGR) could provide sufficient treatment performance of organic and reduced sulfur (TRS) compounds, at 50 C to meet the EPA ''cluster rule'' regulatory limits. The biodegradation of a mixture of organic compounds that could be present in pulp and paper high volume low concentration gas streams was evaluated at 50 C in a bench-scale SSGR. The removal of methanol was followed in particular, and was mathematically modeled to evaluate the effect of process design and operating parameters on methanol removal. Additional tests were performed to obtain mass transfer and biodegradation kinetic parameters for the model. The acclimation of microbial populations capable of degrading TRS compounds from various seed sources was studied in batch reactors at 30 and 50 C. The degradation of TRS compounds in bench-scale SSGR was studied at 20-50 C. Also, the biodegradation kinetic and mass transfer coefficients for alpha-terpinene and gamma-terpinene were studied. Finally, a pilot plant was constructed and operated at Simpson pulp and paper mill in Tacoma, WA.
Date: March 14, 2001
Creator: Stensel, H. David & Strand, Stuart E.
Partner: UNT Libraries Government Documents Department

Energy and environmental research emphasizing low-rank coal--Task 4.4: Development of supercritical fluid extraction methods for the quantitation of sulfur forms in coal

Description: Current analytical methods are inadequate for accurately measuring sulfur forms in coal. This task was concerned with developing methods to quantitate and identify major sulfur forms in coal based on direct measurement (as opposed to present techniques based on indirect measurement and difference values). The focus was on the forms that were least understood and for which the analytical methods have been the poorest, i.e., organic and elemental sulfur. Improved measurement techniques for sulfatic and pyritic sulfur also need to be developed. A secondary goal was to understand the interconversion of sulfur forms in coal during thermal processing. This task had as its focus the development of selective extraction methods that will allow the direct measurement of sulfur content in each form. Therefore, selective extraction methods were needed for the major sulfur forms in coal, including elemental, pyritic, sulfatic, and organic sulfur. This study was a continuation of that of previous analytical method development for sulfur forms in coal which resulted in the successful isolation and quantitation of elemental and sulfatic sulfur. Super- and subcritical extractions with methanol or water with and without additives were investigated in an attempt to develop methods for pyritic and organic sulfur forms analysis in coal. Based on these studies, a sequential extraction scheme that is capable of selectively determining elemental, sulfatic, pyritic and two forms of organic sulfur is presented here.
Date: April 1, 1995
Creator: Timpe, R.C.
Partner: UNT Libraries Government Documents Department