Blind Canyon Research Articles

Carbons prepared from coals for anodes of lithium-ion cells

Carbons were prepared by pyrolysing eight different coals from the Argonne Premium coal sample bank at temperatures near 1000 °C. Electrochemical cells were made to study lithium insertion in these carbons. The electrochemical behavior and physical properties of these pyrolysed coals was compared to that of pyrolysed sugar, PVC and pitch which we have studied carefully before. Using powder X-ray diffraction and small angle X-ray scattering (SAXS), we show that pyrolysed coals which have the smallest fraction of parallel-stacked graphene layers and hence the largest number of nanoscopic pores per unit mass, have the largest capacity for lithium insertion. A reversible capacity of about 450 mAh/g was attained for lithium/carbon cells made from Blind Canyon Seam coal.

Catalytic Coprocessing of Plastics with Coal and Petroleum Resid Using NiMo/Al2O3

Coprocessing of waste plastics with coal and with petroleum resid was investigated to determine the effect of resid on reactivity and conversion. The coal used in this study was Blind Canyon bituminous coal, the resids were Maya and Manji, and the model plastics tested were polystyrene, poly(ethylene terephthalate) (PET), and low-density polyethylene (LDPE). Three systems, the individual species, binary combinations, and ternary combinations, were reacted at conditions of 430 °C and 8.7 MPa of H2 introduced at ambient temperature for 60 min of reaction time. Presulfided NiMo/Al2O3 was used as the catalyst, typically at 1 wt % loading, although other catalyst loading levels of 3 and 10 wt % were tested. Under these conditions polystyrene and PET reacted readily, while LDPE was difficult to convert. Binary reactions with resids resulted in high conversions of ∼94% from polystyrene and PET, while the reactions with LDPE yielded somewhat less conversion of ∼72%. By contrast, reactions of plastics with coal co...

Free radical monitoring of the coprocessing of coal with chemical components of waste tires

The effects of a Michelin tire tread and its various chemical components (butadiene rubber, aromatic oil, carbon, sulfur, ZnO) on the free radical intensities N of Blind Canyon coal using in-situ electron spin resonance spectroscopy are reported from ambient to 500°C. These experiments show that the tire tread and its components lower the temperature of thermal cracking of the coal and promote enhanced cracking as evidenced by increased magnitudes of N for temperatures below 440°C. These results support the reported improved liquefaction of the coal with waste tire polymers.

95/05787 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/PETC`s 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 catalyst loadings up to 1 wt%. Catalytic activity is measured in terms of tetrahydrofuran conversion, heptane conversion, the amount of 9,10-dihydrophenanthrene in the product, and the gas yield. Several catalysts have been evaluated including a commercially available pyrite, a sulfated iron oxide from the University of Pittsburgh, and several preparations of 6-line ferrihydrites from Pacific Northwest Laboratories. Results have demonstrated that significant differences in activity can be detected among these catalysts.

Biogeneration of Iron-Based Catalyst Precursors by Acidianus brierleyi on High- and Low-Pyrite Coals for Direct Liquefaction

Treatment of high-pyrite, high-sulfur Illinois (IBC) coals and pyrite-free Blind Canyon (DECS) coal with added pyrite in the presence of Acidianus brierleyi showed formation of iron oxyhydroxide (FeOOH) particles and subsequent sulfiding caused enhancement in liquefaction and oil yield. IBC No. 101 and 105, and DECS No. 17 containing different amounts of pyrite were treated with A. brierleyi to evaluate its effect on FeOOH formation. Chemical analysis of the liquid phase and Mossbauer analysis of the coals revealed that all the biotreated coals showed significant reduction in pyrite after 21 days (or less with pH alteration in the middle of IBC No. 105 coal run) of incubation. Further data on bioprocessed coals obtained from Mossbauer spectroscopy verified the formation of an FeOOH phase, which acts as a catalyst precursor for direct coal liquefaction (DCL). The direct liquefaction conversion and oil yield of the biotreated DECS No. 17 coal with added pyrite increased by 14 and 5%, respectively, over the control which did not contain A. brierleyi.

Hydroxyl radical generation by coal mine dust: Possible implication to coal workers' pneumoconiosis (CWP)

Occupational exposure to coal mine dust causes coal workers' pneumoconiosis (CWP) and other pulmonary diseases by mechanisms that remain unclear. Because the hydroxyl radicals ( ·OH) may play an important role in the pathogenesis of CWP, we studied the potential role of bituminous coal mine dust samples for catalyzing the generation of ·OH from hydrogen peroxide (H 2O 2). These coal mine dusts evaluated represented two geographic areas with diversity in CWP prevalence. Electron spin resonance (ESR), with the aid of spin trapping techniques, was used to measure the ·OH radical generation. Bituminous coal mine dusts representing the Pittsburgh seam in the eastern United States and Blind Canyon seam in the mid-westem United States were used together with a standard coal dust obtained from the National Institute of Standards and Technology, Galthersburg, MD. All the coal mine dust samples generated varying levels of ·OH radicals from H 2O 2 in the presence of a ·OH spin trap 5,5,-dimethyl-l-pyrroline-N-oxide (DMPO). ·OH radical generation by the coal from H 2O 2 was effectively inhibited by deferoxamine and catalase, but only partially inhibited by superoxide dismutase. Metal chelators DETAPAC and EDTA enhanced the radical generation. These results indicated that the Fenton reaction is predominantly involved in the generation of ·OH radicals from H 2O 2. The ·OH-generating potential of all the coal dusts showed a positive correlation with the surface iron content of coal mine dusts. In addition, the potential to induce lipid peroxidation by the coal samples exhibited a good correlation with the available surface iron. Based on the results presented here, we propose that higher concentrations of surface iron in coal mine dust may be involved in the generation of increased levels of ·OH radicals and may play an important role in the development of CWP in different coal mining areas.

XPS Studies of Residues from Liquefaction of Blind Canyon Coal Mixed with an Iron-Based Catalyst

X-ray photoelectron spectroscopy (XPS) has been used to investigate the surface and bulk characteristics of residue from liquefaction of Blind Canyon coal mixed with an iron-based catalyst. The liquefaction of Blind Canyon coal was investigated at three different processing times (17, 30, and 60 min); residues were studied by XPS. It is shown that the concentration of elements at the outermost surface layer of samples, measured by XPS, is different from the bulk. Ar + ion sputtering followed by XPS was carried out to delineate the differences in the distribution of elements and chemical changes that occurred as the exposed surface varied from initial surface to the bulk

Reactivity of Argonne coals in the presence of cyclic olefins and other donors

The reactivity of eight coals from the Argonne Premium Sample Bank ranging in rank from lignite to low volatile bituminous coal was evaluated in the presence and absence of hydrogen donors. The effect of highly reactive cyclic olefins, isotetralin and hexahydroanthracene (HHA), on coal conversion to tetrahydrofuran soluble material was compared to that of more conventional hydroaromatic donors — tetralin (TET), dihydroanthracene (DHA), and octahydroanthracene (OHA). The Argonne coals were ranked according to their reactivity in an inert solvent, hexadecane, and in Maya resid. These rankings, based on averages, agreed with those calculated by a computed signal-to-noise ratio which measures simultaneously average and variability of coal conversion. The high volatile bituminous coals, Illinois No. 6, Western Kentucky No. 9, Pittsburgh No. 8, and Blind Canyon, were the most reactive. The three-ring hydrogen donors, DHA and HHA, were the most effective for transferring hydrogen to coal, whereas OHA and TET were the least effective. The reaction products obtained from each of the hydrogen donors were different and specific to each reaction. The reactivity of the coal, the ease and effectiveness of hydrogen donation from the donor, and, to a lesser degree, the solvent medium present affected the extent of reaction occurring for each coal system.

Hydrogenolytic activity of soluble and solid iron-based catalysts as related to coal liquefaction efficiency

A comparative activity study of soluble and solid Fe-containing catalysts for hydrogenolysis of (1) coal-simulating compounds, i.e., 2-isopropylnaphthalene (IPN), 1,2-dinaphthylethane (DNE), and diphenylmethane (DPM), and (2) a Blind Canyon coal sample (designated as DECS-17) was performed. The soluble catalysts were supported on inert SiO 2 and included aqua complexes of various Fe salts, i.e., sulfate, acetate, and chloride. The solid catalysts consisted of finely dispersed superacids, i.e., Fe 2 O 3 /SO 4 2− and ZrO 2 /SO 4 2− . The activity of the soluble catalysts is ascribed to the aqua complex ion [Fe(H 2 O) 6 ] 3+ , which is preformed or formed in situ in the presence of water and could act as a protonic acid by ligand dissociation

Nano-Crystalline Powders and Suspensions Generated Using A Flow-Through Hydrothermal Process, Part II: Applications

ABSTRACTUltra-fine, nano-crystalline six-line ferrihydrite (5Fe2O3-9H2O) and cubic zirconia (ZrÜ2) powders have been produced using the Rapid Thermal Decomposition of precursors in Solution (RTDS) technology. Nano-crystalline RTDS six-line ferrihydrite powder used as an in situ precursor for first-stage direct coal liquefaction catalysts increased the liquefied products from Blind Canyon Seam coal by 22% absolute over thermal background at 350°C. Initial sintering studies performed on nano-crystalline RTDS ZrO2 powder have also been presented and compared to predictions made from theories derived for micro-crystalline powders.

Testing iron-based catalysts for direct coal liquefaction using in situ electron spin resonance spectroscopy

In this work, nine Fe-based catalysts (Fe 2 O 3 /SO 4 (1), Fe 2 O 3 /SO 4 (2), Mo/Fe 2 O 3 /SO 4 , Fe 2 O 3 /SnO 2 /SO 4 , Fe 2 O 3 /MoO 4 , Fe 2 O 3 /WO 4 , FeOOH/SO 4 , Mo/FeOOH/SO 4 , and Fe 7 S 8 ) are tested for their hydrocracking abilities of Blind Canyon coal using in situ high-temperature ESR (electron spin resonance) spectroscopy of coal free radicals. The catalysts are characterized for chemical phase and for their particle size by X-ray diffraction. The intensities N of the free radicals are measured from room temperature to 500 °C in flowing H 2 gas, with and without the catalyst plus elemental sulfur loadings, in the ratios Fe/coal ≃ 1 % and Fe/S = 1/2. It is found that, above about 350 °C, the catalyst loaded samples yield higher N

Composition of combustion gases and particles in a pulverized coal-fired reactor

This paper presents a comprehensive set of in situ gas species concentration measurements of O 2 , CO 2 , CO, NO x , SO x , HCN, and NH 3 and particle composition measurements of ash, carbon, hydrogen, and nitrogen taken in a 0.3 MW e pulverized coal flame in a controlled profile reactor with well-defined and controlled wall temperature and inlet flow characteristics. An evaluation of the effects of varying coal mass mean particle size, equivalence ratio, and secondary air swirl number on the measured data is shown through a graphical analysis of the data. Mass and carbon balances were calculated to ensure closure and overall accuracy of the data set. A series of seven combustion tests were conducted using Utah Blind Canyon high volatile bituminous coal

Effective optical properties of pulverized coal particles determined from FT-IR spectrometer experiments

For accurate modeling of radiative transfer in combustion systems, radiative properties of combustion gases and particles are required. The particle properties are usually determined from the Lorenz-Mie theory assuming they are spherical in shape and their optical properties, i.e., the complex index of refraction data, are available. In the present study, an FT-IR spectrometer has been used to determine the «effective» optical properties of Blind Canyon and Kentucky no. 9 coals suspended in KBr pellets, within the wavelength interval of 2-20 μm. A detailed inversion analysis based on the Lorenz-Mie theory is employed to reduce the measured transmission data to a complex index of refraction spectra. In the analysis, the effects of both absorption and scattering by coal particles are accounted for

Microscopic studies on the dispersion of iron/molybdenum bimetallic catalysts in hydrotreated Blind Canyon, Wyodak and Pittsburgh #8 coals

The dispersion and reactivity of an iron/molybdenum coal liquefaction catalyst was investigated in three Argonne coals. Blind Canyon, Wyodak and Pittsburgh # 8 coal samples were impregnated with a 1 wt% Fe and 1 wt% Mo liquefaction catalyst using both ultrasonic and incipient wetness techniques. The yields of THF solubles in demineralized Blind Canyon coal indicate no significant advantage in the use of ultrasound as the impregnation technique. Results of electron probe microanalysis (EPMA) show that the catalyst is coated on the surface of impregnated, demineralized coal particles prior to hydropyrolysis at 350°C and 2000 psig H 2. EPMA micrographs obtained after hydropyrolysis indicate that the catalyst has entered the interior of demineralized coal particles. Mobility of iron and molybdenum evidently occurs during hydropyrolysis and possibly is facilitated by the liquid phase present in the demineralized coal and the amount of porosity. Corresponding EPMA data obtained from impregnated undemineralized coal samples are ambiguous.

Three-dimensional NMR microscopic imaging of coal swelling in pyridine

Results from two different NMRI techniques for spatially mapping the mobile proton distribution in coals swollen with pyridine-d 5 or pyridine are reported. Three-dimensional (3-D) back-projection methods using a reconstruction algorithm based on a Radon transform inversion were employed to image a specimen of Utah Blind Canyon coal swollen with pyridine-d 5 . Images of the mobile macromolecular structure of Utah coal resulting from solvent swelling were obtained using T 1 contrasting. Solvent penetration was also monitored using T 2 weighting in a 3-D gradient-recalled echo pulse sequence and image reconstruction by 3-D Fourier transform methods

Moisture release from Argonne premium coal samples. A quantitative phosphorus-31 NMR spectroscopic study

To study the possibility of differentiating types of moisture in coals, four Argonne Premium Coal Samples (APC's) (Beulahh-Zap, Illinois No. 6, Blind Canyon, and Pittsburgh No. 8) having a range of moisture contents were extracted at 23°C with pyridine, dioxane, dimethoxyethane, tetrahydrofuran, ethyl methyl ketone, and acetonitrile. The moisture contents in the extracts were determined after 1/4, 1/2, 1, 2, 4, and 8 h by 31 P NMR spectroscopy using the tagging reagent ClP(O)Ph 2 . From the lowest rank coal almost all of the water was extracted with pyridine within the first 15 min and for the remaining coals studied this process was essentially complete after 8 h. The water extracted from each coal with the least efficient extraction solvent (dioxane or dimethoxyethane) within 15 min is considered as a reasonable estimate of the surface moisture

THE EFFECT OF ADDED HETEROGENEOUS CATALYSTS ON LOW-SEVERITY COAL LIQUEFACTION

ABSTRACT Liquefaction data in the presence and absence of added catalysts were obtained for two coals from the Argonne premium Sample Bank (Beulah-Zap lignite and Utah Blind Canyon high volatile bituminous). Experiments were carried out in tubing bomb microautoclave batch reactors over a broad temperature range (310 to 425 °C), and THF and hexane conversion profiles were measured at residence times of 5, 10, 15, and 30 minutes in order to elucidate the effect of both time and temperature at reaction conditions ranging from low to high severity. All runs were carried out in a non-donor vehicle (l-methylnaphthalene) using powdered presulfided Shell 324 as the catalyst. The results generally reflect the expected trends for catalyst on coal conversion, in that the primary influence of catalyst was found to be in terms of promoting conversion of coal to hexane solubles. A hexane selectivity parameter was developed and utilized to provide insight into the role and effect of catalyst.

Changes in Surface Area, Pore Structure and Density during Formation of High-temperature Chars from Representative U.S. Coals

Multiple techniques (CO2 and N2 adsorptions, NMR spin relaxation of adsorbed water, He pycnometry and Hg porosimetry) have been combined in a comprehensive study to determine changes in surface area (CO2 and nitrogen), density (solid, particle and bulk), and pore structure (pore size and volume distributions of micro-, meso- and macro-pores) in high-temperature char formation from rank representative U.S. coals of the ANL and PETC Banks (i.e. Beulah Zap, Dietz, Utah Blind Canyon, Pittsburgh No.8 and Pocahontas No.3). Chars were formed at high heating rates in a flat-frame burner (maximum temperature of 1473 K), a process representative of char formation in pulverized coal combustion. Most of the surface area of the coals was found in micropores with radii less than 1.5 nm, while 95% or more of the pore volume in the coals (85% of that in chars) was contained in mesopores less than 20 nm). During the high-temperature formation of char in a flame: (I) CO2 surface areas (involving mainly micropores, rpore < 1.5 nm) increase two- to three-fold, while N2 surface areas (involving mesopores. 1.5 nm < rpore < 20 nm) increase 20–200-fold; (2) solid densities increase about 25% due to graphitization, while particle densities decrease by about a factor of two due to large increases in particle porosity; (3) pore volumes increase 5–10-fold; and (4) total porosities increase three- to four-fold, most of this increase occurring in the macropore range. The larger surface areas and porosities of chars relative to coals may be explained by (i) the removal by pyrolysis of strongly adsorbed molecules or volatile hydrocarbons from micropores and small mesopores that would otherwise hinder access of CO2 and N2 molecules; (ii) the creation of new pores during the restructuring process involved in charification; and (iii) opening up by gasification with oxygen of new pores previously blocked to gas adsorption. The preparation conditions (e.g. atmosphere, heating rate and temperature) greatly affect the physical properties including the surface area, porosity and density of the resulting chars. The degree of carbon burnout is an important correlating factor affecting these properties.

E.p.r. and ENDOR studies of Argonne Premium coals doped with nitroxide spin probes

E.p.r. and ENDOR measurements of five Argonne Premium Coal Samples (APCS) varying in rank from low-volatile (Pocahontas, No. 5) to lignite (Beulah-Zap, No. 8) either undoped or doped with nitroxide spin probes and a series of nitroxide radicals are reported. For the first time proton hyperfine coupling constants have been deduced from ENDOR studies of tempamine, DCT-tempamine and a carboxaldimine nitroxide radical in toluene solution at 185 K. Proton matrix ENDOR signals at the free proton frequency and a broad ENDOR signal were observed for all undoped APCS, except for a sample of Beulah-Zap in which no proton ENDOR lines were observed. For the spin probe doped Beulah-Zap, Blind Canyon and Illinois No. 6, the ENDOR spectrum consisted of the lines observed for the undoped coal, and two pairs of proton ENDOR lines with hyperfine couplings of 3.6 MHz and 0.18 MHz. The lines with the coupling of 3.6 MHz are due to nitroxide radicals, assigned by similarity to the ENDOR results of the nitroxide spin probes in toluene solution at 120 K. The existence of the second pair of lines with hyperfine coupling constant 0.18 MHz was assumed to be due to the interaction of surrounding matrix coal protons with the nitroxide species, substantiating an earlier report of hydrogen bonding to the nitroxide spin probe.

Stratigraphy of the Coal-Bearing Blackhawk Formation on North Horn Mountain, Wasatch Plateau, Utah

Coal- bearing rocks of the Cretaceous Blackhawk Formation crop out along the eastern margin of the Wasatch Plateau in central Utah. On North Horn Mountain the Blackhawk Formation ranges from 215 to 290 meters in thickness and consists of interbedded sandstone, shale, siltstone, carbonaceous shale, coal, and limestone. The lower half of the formation, which contains the economically important coal beds, was deposited predominantly in a shallow water , wave-modified delta system. The upper half of the unit was deposited in fluvial environments of meandering streams and floodplains. The source for the clastic sediments of the Blackhawk Formation was to the west. Potentially minable coal exists in the Hiawatha and Blind Canyon beds and possibly in the Bear Canyon bed. The thickest beds were measured in the southeastern part of the study area, with 5.3 meters of the Blind Canyon bed found in one measured section. These coals are high quality and have lateral continuity, but the thickness varies and scattered wants and splits are to be found. Coal reserves on North Horn Mountain are large and should become an important source of supply for local and regional markets.