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Full-Text Articles in Engineering
Determination Of An Ethane Intermolecular Potential Model For Use In Molecular Simulations From Ab Initio Calculations, Richard L. Rowley, Tapani A. Pakkanen, Yan Yang
Determination Of An Ethane Intermolecular Potential Model For Use In Molecular Simulations From Ab Initio Calculations, Richard L. Rowley, Tapani A. Pakkanen, Yan Yang
Faculty Publications
Counterpoise-corrected, supermolecule, ab initio energies obtained at the MP2/6-311+G(3df, 2pd) level were computed for 22 different relative orientations of two ethane molecules as a function of the separation distance between the molecular centers. These energies were used to regress the parameters in several simple, analytical, interatomic or site-site models that can be used for implementation in molecular simulations. Sensitivity analysis indicated that the inter molecular potential surface is insensitive to the C-C interactions and that the parameters in the C-C model are coupled and unobtainable from the dimer energies. Representation of the potential surface can be made in terms of …
Simultaneous Capture And Mineralization Of Coal Combustion Flue Gas Carbon Dioxide (Co2), Morris D. Argyle, Katta J. Reddy, Sanil John, Hollis Weber, Pradip Bhattacharyya, David T. Taylor, Mikol Christensen, Thomas Foulke, Paul Fahlsing
Simultaneous Capture And Mineralization Of Coal Combustion Flue Gas Carbon Dioxide (Co2), Morris D. Argyle, Katta J. Reddy, Sanil John, Hollis Weber, Pradip Bhattacharyya, David T. Taylor, Mikol Christensen, Thomas Foulke, Paul Fahlsing
Faculty Publications
The mineral carbonation, a process of converting CO2 into stable minerals (mineralization), has been studied extensively to capture and store CO2. However, most of the mineral carbonation studies have been largely investigated at lab scale. Preliminary and pilot scale studies for accelerated mineral carbonation (AMC) were conducted at one of the largest coal-fired power plants (2120 MW) in the USA by reacting flue gas with fly ash particles in a fluidized bed reactor. In the preliminary experiments, flue gas CO2 and SO2 concentrations decreased from 13.0 to 9.6% and from 107.8 to 15.1 ppmv, respectively during the first 2 min. …
Nitrogen Transformations During Secondary Coal Pyrolysis, Haifeng Zhang, Thomas H. Fletcher
Nitrogen Transformations During Secondary Coal Pyrolysis, Haifeng Zhang, Thomas H. Fletcher
Faculty Publications
A CO/H2/O2/N2 flame was operated under fuel-rich conditions in a flat flame reactor to provide a high-temperature, oxygen-free environment to study secondary reactions of coal volatiles. The distributions of fuel nitrogen in the devolatilization products of four coals, ranging from high volatile bituminous to lignite, were obtained at gas temperatures ranging from 1159 to 1858 K. It was found that the initial nitrogen released was contained almost exclusively in the tar for all coals. Release of nitrogen from the char as light gases started at a later stage than tar nitrogen release. During secondary reactions, …
Simulation Of Coal Pyrolysis In Plasma Jet By Cpd Model, Yajun Tian, Kechang Xie, Suyu Zhu, Thomas H. Fletcher
Simulation Of Coal Pyrolysis In Plasma Jet By Cpd Model, Yajun Tian, Kechang Xie, Suyu Zhu, Thomas H. Fletcher
Faculty Publications
Reaction of coal in a plasma jet is complex and extremely rapid, and acetylene and carbon monoxide are the main products in the pyrolysis gas. Coal pyrolysis is assumed as the first step reaction when coal is injected into hot plasma jet with initial average temperature of 3700 K. Chemical percolation devolatilization (CPD) is employed first to simulate this procedure in mechanism. The calculation results indicate coal pyrolysis rate in plasma jet is very fast and the retention time of coal staying in reactor is only several milliseconds. Comparing the calculation with experiment result, it was concluded that the CPD …
Small-Angle X-Ray Studies Of Soot Inception And Growth, Jan P. Hessler, Soenke Seifert, Randall E. Winans, Thomas H. Fletcher
Small-Angle X-Ray Studies Of Soot Inception And Growth, Jan P. Hessler, Soenke Seifert, Randall E. Winans, Thomas H. Fletcher
Faculty Publications
The high spectral intensity of X-rays produced by the undulator at the Basic Energy Sciences Synchrotron Radiation Center of Argonne's Advanced Photon Source has allowed us to perform small-angle X-ray scattering (SAXS) studies of the initial distribution of soot particles formed by various fuels. SAXS provides an in situ probe of the morphology of soot in the region between 1 and 100 nm and complements the ex situ technique of electron microscopy. The basic aspects of SAXS and its potential are illustrated with measurement on a laminar flame of acetylene in air. The more complex fuel toluene has been studied …
Transformations Of Coal-Derived Soot At Elevated Temperature, Thomas H. Fletcher, Jim Rigby, Jinliang Ma, Brent W. Webb
Transformations Of Coal-Derived Soot At Elevated Temperature, Thomas H. Fletcher, Jim Rigby, Jinliang Ma, Brent W. Webb
Faculty Publications
Coal pyrolysis experiments were performed in the post-flame region of a CH4/H2/air flat-flame burner operating under fuel-rich conditions, where the temperature and gas compositions were similar to those found in the near-burner region of an industrial pulverized coal-fired furnace. Volatiles released from the coal particles formed a cloud of soot particles surrounding a centrally fed coal/char particle stream. Soot samples were collected from the cloud at different residence times using a water-cooled, nitrogen-quenched probe. The soot samples were then analyzed for their elemental compositions of carbon, hydrogen, nitrogen, sulfur, and (by difference) oxygen plus inorganic matter. …
13-C Nmr Analysis Of Soot Produced From Model Compounds And A Coal, Mark S. Solum, Adel F. Sarofim, Ronald J. Pugmire, Thomas H. Fletcher, Haifeng Zhang
13-C Nmr Analysis Of Soot Produced From Model Compounds And A Coal, Mark S. Solum, Adel F. Sarofim, Ronald J. Pugmire, Thomas H. Fletcher, Haifeng Zhang
Faculty Publications
Soot samples, including the associated organics, produced from an Illinois No. 6 coal (five samples) and two model compounds, biphenyl (three samples) and pyrene (two samples), have been studied by 13C NMR methods. The coal soot data served as a guide to selection of the temperature range that would be most fruitful for investigation of the evolution of aerosols composed of soot and tars that are generated from model compounds. The evolution of the different materials in the gas phase followed different paths. The coal derived soots exhibited loss of aliphatic and oxygen functional groups prior to significant growth …