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Polychlorodibenzo-p-dioxin and polychlorodibenzo-furan removal and destruction.

Description: This report provides a short summary of technologies used to destroy or separate dioxins/furans from environmental samples. It is meant as a resource for developing a technology employing magnetic particles as an engineering vehicle for large-scale, cost-effective destruction of dioxins/furans in fresh waters or sludges/soils.
Date: September 30, 2003
Creator: Patel, S.; Kaminski, M. D. & Nunez, L.
Partner: UNT Libraries Government Documents Department

FY 1994 ambient air monitoring report for McMurdo Station, Antarctica

Description: This report presents the results of ambient air monitoring performed during the 1994 fiscal year (FY 1994) in the vicinity of McMurdo Station, Antarctica. Routine monitoring was performed during the 1993-1994 austral summer at three locations for airborne particulate matter less than 10 micrometers (PM-10) and at two locations for carbon monoxide (CO), sulfur dioxide (SO{sub 2}), and nitrogen oxides (NO, NO{sub 2}, and NO{sub x}). Selected PM-10 filters were analyzed for arsenic, beryllium, cadmium, chromium, lead, mercury, and nickel. Additional air samples were collected at three McMurdo area locations and at Black Island for determination of the airborne concentration of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Sampling site selection, sampling procedures, and quality assurance procedures used were consistent with US Environmental Protection Agency guidance for local ambient air quality networks.
Date: December 1, 1994
Creator: Lugar, R.M.
Partner: UNT Libraries Government Documents Department

Polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran formation and emission in the thermal desorption waste treatment process

Description: It is extremely unlikely that significant amounts of polychlorinated dibenzo-p-dioxins (PCDDs) or polychlorinated dibenzofurans (PCDFs) will be emitted in the off-gas stream from the thermal desorption process, or the treated waste, particularly if the baseline design and anticipated operating conditions of the enhanced bench-scale (EBS) system are used. However, because of the acute toxicity of these compounds and because most of the data on their formation have been extrapolated from studies more related to incineration and fire conditions than thermal desorption, specific laboratory tests and specific EBS runs should be performed to monitor the rate of emission of PCDDs and PCDFs under thermal desorption conditions. In general, the following four conditions need to exist for significant amounts of PCDD or PCDF to be formed: (1) the presence of fly ash; (2) the presence of an oxidizing source; (3) a suitable temperature, and (4) the presence of a suitable precursor. Although the EBS system provides some of these conditions, it is unlikely that enough fly ash will be produced in the system to allow a significant amount of PCDD or PCDF formation. Additionally, particulate matter controls will be used to remove airborne particulates from the gas phase. If PCDD/Fs are presented in a waste stream being evaluated in the EBS, they will likely volatilize in the kiln and subsequently condense in the venturi scrubber system.
Date: March 1, 1995
Creator: Leckey, J.H.
Partner: UNT Libraries Government Documents Department

Control of catalytic hydrotreating selectivity with ammonia. [Progress] report, October 1, 1991--December 31, 1991

Description: The focus of our attention has now shifted to the effect of ammonia on hydrodeoxygenation (HDO) of selected model compounds. Scouting studies with 2-phenylphenol (OPP), phenyl ether (PE), 3-ethylphenol (MEP) and dibenzofuran (DBF) indicated some inhibition of hydrogenation activity but with OPP, PE and MEP several products were formed that were not completely identified and kinetic analysis would be difficult. We therefore focused on DBF, with which we have had some experience, and we carried out a series of studies at 3.5 MPa and 360{degrees}C. H{sub 2}S was generated in situ and NH{sub 3} was introduced as supercooled liquid by an ISCO pump to constitute 12 kPa in the reactor. Samples of reaction products were anlayzed by g.c. using a 30-m Supelcowax (high polarity) column. The HDO of the DBF network follows two pathways. There is a hydrogenation route where single-ring products predominate, mostly cyclohexane and cyclobenzene. The other path is a hydrogenolysis route where double-ring compounds predominate, mostly cyclohexylbenzene (CHB), biphenyl (BP), and dicyclohexyl (DCH).
Date: December 31, 1991
Creator: Satterfield, C. N. & Lee, Chung M.
Partner: UNT Libraries Government Documents Department

Control of catalytic hydrotreating selectivity with ammonia. [Quarterly] report, January 1, 1992--March 31, 1992

Description: The hydrogenation of naphthalene in the presence of 0, 24, or 48 kPa of ammonia derived from propyl amine was studied during the hydrodeoxygenation (HDO) of dibenzofuran (DBF). A new sample of sulfided NiMo/Al{sub 2}O{sub 3} catalyst at 360{degrees}C, 6.9 MPa total H{sub 2} pressure in a vapor phase tubular reactor was used. As a base-line the HDO of DBF was also studied in the absence of both naphthalene and ammonia. Ammonia inhibited both the HDO of dibenzofuran and the hydrogenation of naphthalene. The addition of ammonia may not be suitable if a high conversion of HDO is desired. 12 figs.
Date: July 1, 1992
Creator: Satterfield, C. N. & Lee, C. M.
Partner: UNT Libraries Government Documents Department

Control of catalytic hydrotreating selectivity with ammonia. [Hydrodeoxygenation]

Description: The focus of our attention has now shifted to the effect of ammonia on hydrodeoxygenation (HDO) of selected model compounds. Scouting studies with 2-phenylphenol (OPP), phenyl ether (PE), 3-ethylphenol (MEP) and dibenzofuran (DBF) indicated some inhibition of hydrogenation activity but with OPP, PE and MEP several products were formed that were not completely identified and kinetic analysis would be difficult. We therefore focused on DBF, with which we have had some experience, and we carried out a series of studies at 3.5 MPa and 360{degrees}C. H{sub 2}S was generated in situ and NH{sub 3} was introduced as supercooled liquid by an ISCO pump to constitute 12 kPa in the reactor. Samples of reaction products were anlayzed by g.c. using a 30-m Supelcowax (high polarity) column. The HDO of the DBF network follows two pathways. There is a hydrogenation route where single-ring products predominate, mostly cyclohexane and cyclobenzene. The other path is a hydrogenolysis route where double-ring compounds predominate, mostly cyclohexylbenzene (CHB), biphenyl (BP), and dicyclohexyl (DCH).
Date: January 1, 1991
Creator: Satterfield, C. N. & Lee, Chung M.
Partner: UNT Libraries Government Documents Department

Novel catalysts for upgrading coal-derived liquids. Final technical progress report

Description: Research described in this report was aimed at synthesizing and evaluating supported Mo oxynitrides and oxycarbides for the selective removal of nitrogen, sulfur and oxygen from model and authentic coal-derived liquids. The Al{sub 2}O{sub 3}-supported oxynitrides and oxycarbides were synthesized via the temperature programmed reaction of supported molybdenum oxides or hydrogen bronzes with NH{sub 3} or an equimolar mixture of CH{sub 4} and H{sub 2}. Phase constituents and composition were determined by X-ray diffraction, CHN analysis, and neutron activation analysis. Oxygen chemisorption was used to probe the surface structure of the catalysts. The reaction rate data was collected using specially designed micro-batch reactors. The Al{sub 2}O{sub 3}-supported Mo oxynitrides and oxycarbides were competitively active for quinoline hydrodenitrogenation (HDN), benzothiophene hydrodesulfurization (HDS) and benzofuran hydrodeoxygenation (HDO). In fact, the HDN and HDO specific reaction rates for several of the oxynitrides and oxycarbides were higher than those of a commercial Ni-Mo/Al{sub 2}O{sub 3} hydrotreatment catalyst. Furthermore, the product distributions indicated that the oxynitrides and oxycarbides were more hydrogen efficient than the sulfide catalysts. For HDN and HDS the catalytic activity was a strong inverse function of the Mo loading. In contrast, the benzofuran hydrodeoxygenation (HDO) activities did not appear to be affected by the Mo loading but were affected by the heating rate employed during nitridation or carburization. This observation suggested that HDN and HDS occurred on the same active sites while HDO was catalyzed by a different type of site.
Date: March 31, 1995
Creator: Thompson, L.T.; Savage, P.E. & Briggs, D.E.
Partner: UNT Libraries Government Documents Department

Control of catalytic hydrotreating selectivity with ammonia. [Hydrodeoxygenation]

Description: The hydrogenation of naphthalene in the presence of 0, 24, or 48 kPa of ammonia derived from propyl amine was studied during the hydrodeoxygenation (HDO) of dibenzofuran (DBF). A new sample of sulfided NiMo/Al{sub 2}O{sub 3} catalyst at 360{degrees}C, 6.9 MPa total H{sub 2} pressure in a vapor phase tubular reactor was used. As a base-line the HDO of DBF was also studied in the absence of both naphthalene and ammonia. Ammonia inhibited both the HDO of dibenzofuran and the hydrogenation of naphthalene. The addition of ammonia may not be suitable if a high conversion of HDO is desired. 12 figs.
Date: January 1, 1992
Creator: Satterfield, C.N. & Lee, C.M.
Partner: UNT Libraries Government Documents Department

Production of jet fuels from coal-derived liquids

Description: Samples of jet fuel (JP-4, JP-8, JP-8X) produced from the liquid by-products of the gasification of lignite coal from the Great Plains Gasification Plant were analyzed to determine the quantity and type of organo-oxygen compounds present. Results were compared to similar fuel samples produced from petroleum. Large quantities of oxygen compounds were found in the coal-derived liquids and were removed in the refining process. Trace quantities of organo-oxygenate compounds were suspected to be present in the refined fuels. Compounds were identified and quantified as part of an effort to determine the effect of these compounds in fuel instability. Results of the analysis showed trace levels of phenols, naphthols, benzofurans, hexanol, and hydrogenated naphthols were present in levels below 100 ppM. 9 figs., 3 tabs.
Date: June 1, 1990
Creator: Knudson, C.L.
Partner: UNT Libraries Government Documents Department

Interactive chemistry of coal-petroleum processing

Description: The objective of this program is to investigate the interactive thermal and catalytic chemistry of coal and petroleum processing using model compounds and actual petroleum-coal materials. This quarter the interactive catalytic chemistry of model coal and petroleum systems was investigated using combined catalysts of molybdenum naphthenate and vanadyl acetylacetonate. This combination was performed in order to evaluate the effect of the presence of an indigenous residuum metal, vanadium, on model reactions that occur in coprocessing. In addition, the effect of the vanadium sulfide on the catalysts of in situ sulfided molybdenum naphthenate was investigated. The following reactions were investigated: catalytic hydrodeoxygenation of dibenzofuran, effect of vanadium sulfide in combined catalyst systems on dibenzofuran hydrodeoxygenation, catalytic hydrodesulfurization of dibenzothiophene, effect of vanadium sulfide in combined catalyst systems on dibenzothiophene hydrodesulfurization, catalytic hydrogenation of fluorene, effect of vanadium sulfide in combined catalyst systems on fluorene hydrogenation, catalytic hydrodenitrogenation of carbazole, and effect of vanadium sulfide in combined catalyst systems on carbazole hydrodenitrogenation.
Date: January 1, 1989
Creator: Curtis, C.W.; Guin, J.A. & Tarrer, A.R.
Partner: UNT Libraries Government Documents Department

Toxic organic compounds from energy production

Description: The US Department of Energy's Office of Health and Environmental Research (OHER) has supported work in our laboratory since 1977. The general theme of this program has been the identification of potentially toxic organic compounds associated with various combustion effluents, following the fates of these compounds in the environment, and improving the analytical methodology for making these measurements. The projects currently investigation include: an improved sampler for semi-volatile compounds in the atmosphere; the wet and dry deposition of dioxins and furans from the atmosphere; the photodegradation and mobile sources of dioxins and furans; and the bioaccumulation of PAH by tree bark. These projects are all responsive to OHER's interest in the pathways and mechanisms by which energy-related agents move through and are modified by the atmosphere''. The projects on gas chromatographic and liquid chromatographic tandem mass spectrometry are both responsive to OHER's interest in new and more sensitive technologies for chemical measurements''. 35 refs., 9 figs.
Date: September 20, 1991
Creator: Hites, R.A.
Partner: UNT Libraries Government Documents Department

PCDDs (polychlorinated dibenzo-p-dioxins) and PCDFs (polychlorinated dibenzofurans) in humans

Description: Numerous instances of human exposure to polychlorinated dibenzo-p- dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) have been documented. Following the development of sufficiently specific and sensitive analytical methods during the past few years, many reports have appeared on PCDD and PCDF levels in human blood and adipose tissues. Studies have examined the PCDD and PCDF levels resulting from accidental and occupational exposures of various groups, including chemical plant workers, forestry and tannery workers, and Niet Nam veterans who had handled Agent Orange. The general background levels in the US, Federal Republic of Germany, Japan, and Sweden were also determined. The results of these studies indicate that a background level of PCDDs and PCDFs is present in the overall population. In some cases, individuals exposed to specific PCDDs or PCDFs exhibit higher levels than the general population. Isomer distribution patterns are relatively consistent and indicative of sources and metabolism. This paper reviews the available data on human PCDD and PCDF levels in exposed and general populations. 15 refs., 4 figs.
Date: January 1, 1990
Creator: Swanson, S.E. (Midwest Research Inst., Kansas City, MO (USA)) & Erickson, M.D. (Argonne National Lab., IL (USA))
Partner: UNT Libraries Government Documents Department

The thermodynamic properties of 2-aminobiphenyl (an intermediate in the carbazole/hydrogen reaction network)

Description: Catalytic hydrodenitrogenation (HDN) is a key step in upgrading processes for conversion of heavy petroleum, shale oil, tar sands, and the products of the liquefaction of coal to economically viable products. This research program provides accurate experimental thermochemical and thermophysical properties for key organic nitrogen-containing compounds present in the range of alternative feedstocks, and applies the experimental information to thermodynamic analyses of key HDN reaction networks. This report is the first in a series that will lead to an analysis of a three-ring HDN system; the carbazole/hydrogen reaction network. 2-Aminobiphenyl is the initial intermediate in the HDN pathway for carbazole, which consumes the least hydrogen possible. Measurements leading to the calculation of the ideal-gas thermodynamic properties for 2-aminobiphenyl are reported. Experimental methods included combustion calorimetry, adiabatic heat-capacity calorimetry, comparative ebulliometry, inclined-piston gauge manometry, and differential-scanning calorimetry (d.s.c). Entropies, enthalpies, and Gibbs energies of formation were derived for the ideal gas for selected temperatures between 298.15 K and 820 K. The critical temperature and critical density were determined for 2-aminobiphenyl with the d.s.c., and the critical pressure was derived. The Gibbs energies of formation are used in thermodynamic calculations to compare the feasibility of the initial hydrogenolysis step in the carbazole/H{sub 2} network with that of its hydrocarbon and oxygen-containing analogous; i.e., fluorene/H{sub 2} and dibenzofuran/H{sub 2}. Results of the thermodynamic calculations are compared with those of batch-reaction studies reported in the literature. 57 refs., 8 figs., 18 tabs.
Date: December 1, 1990
Creator: Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E. & Nguyen, A.
Partner: UNT Libraries Government Documents Department