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00389 Catalysts, their manufacture and their use in synthesis gas production
04
By-products
related to fuels
99100385
Behavior of limestone as a H2S capture in stream gasification of coal Zhao, Z.-B. et al. Proc. Annu. Int. Pittsbumh Coal Conf., 1997, 14, (10). . I 13-18. The stream gasification of coal mixed with limestone has been investigated in a fluidized-bed reactor in order to determine whether CaCOs acts as a desulphurizing agent. The sulfur content in the coal used was 3.02 wt%. Coal with particle size of 0.21 mm and limestone with 0.125 mm are mixed and a series of limestone/coal mixtures is prepared, in which Ca/S molar ratio is 1.0, 2.0, 2.5, 3.5, 4.5 and 5.5. In the fluidized-bed reactor, the mixtures are heated to 1373 K in HrO-Nr atm and held at that temperature for 30 mm. The gas produced is collected from 573 K to 1373 K. Sulfur in gas samples and in residual solid is analysed. The experimental data establish that CaCOs reacts with HzS from product gas in gasification of coal with limestone. The reaction is strongly limited by both HzS pore diffusion in limestone and pore mouth plugging effect of CaS produced. The experimental results show that, when gasification temperature of coal is above 1123 K, CaS decomposability would increase with increase of steam content in fluidized-bed reactor.
nanotubes Carbon 99100388 pyrolysis of benzene
production
by
catalytic
Benito, A. et al. Carbon, 1998, 36, (5/6), 681-683. Different types of carbon nanostructures were generated by the pyrolysis of benzene at around 600-900°C over nickel powder, possessing a wide range of morphologies. The effects of temperature and time on carbon nanotubes growth were evaluated. The deposited carbon yield was measured, and the quality of the nanotubes was analysed by transmission electron microscopy (TEM). 99199387
Carbon single wall nanotubes elaboration
and
properties Bernier, P. et al. Carbon, 1998, 36, (5/6), 675-680. Interesting new molecules of the fullerene family are yielded by the coevaporation of carbon, in the presence of helium with some other element as catalyst, which have tubular morphologies with a cross-section at the nanoscale but lengths at the macroscale. Using nickel or cobalt based mixtures as catalyst with the electric arc technique, one obtains single wall carbon nanotubes in large quantities, with an average diameter of 1.4 nm and which assemble themselves in highly crystalline bundles containing a few tens of elements. X-ray and electron diffraction have been used to characterize the crystalline nature of individual bundles. The diameter dispersion has been studied in detail using Raman spectroscopy which shows impressively well-resolved structures of the observed modes. A majority of armchair tubes is observed, but some other configurations are also present with slightly different diameters. 99100388
Catalysts
and
method
for
synthetic
gas
production Kata, T. et al Jpn. Kokai Tokkyo Koho JP 10 174,869 [98 174,869] (Cl. BOlJ23/72), 30 Jun 1998, Appl. 96/338,283, 18 Dee 1996; 4 pp. (In Japanese) Copper is contained in the catalysts for manufacturing synthesis gas from di-Me ether and CO?. In synthesis gas manufacture, gas mixtures containing di-Me ether and CO2 are brought into contact with the catalysts. By using the catalysts at low temperature (200-500”) high-yield production of the gas (H and CO) is attained.
Catalysts, their manufacture, synthesis gas production
99199389
and their use in
Shikada, T. et al. Jpn. Kokai Tokkyo Koho JP 10 174,865 [98 174,865] (Cl. BOlJ23/44), 30 Jun 1998, Appl. 96/339,757, 19 Dee 1996; 6 pp. (In Japanese) In the manufacture of synthesis gas from d&Me ether and steam or COz,the catalysts use basic metal oxides which support palladium. The catalysts are manufactured by loading palladium on-the oxides and then treating the materials with aqueous basic solutions. In synthesis gas manufacture, gas mixtures containing di-Me ether and steam or COz are brought into contact with the catalysts. By using the catalysts at low temperature (200-600”) high-yield production of the gas (H and CO) is attained.
Catalytic synthesis of high-value chemicals and materials from coal
99100390
Song, C. and Schobert, H. H. Proc. Annu. Int. Pittsburgh Coal Conf., 1997, 14, (28), 17-32. A review was made on the production of chemical intermediates by selective catalytic conversion from coal derived feedstocks.
Characterization of hot-gas filter ash under PFBC 99/00391 operating conditions Henderson, A. K. et al. Proc. ht. Conf. Fluid. Bed Combust., 1997, 14, (2), 677-682. In this programme, the objective was to perform bench-scale dynamic tests of ash formation and long-term ash cake formation in pressurized fluidizedbed combustion (PFBC) systems to help in the development of methods to predict possible filter bridging problems and suggest possible strategies for mitigating these problems. During the programme, four ash formation tests using a washed coal from the Consol Enlow Fork mine, with two size distributions of Plum Run dolomite at two different temperatures, were
38
Fuel and Energy Abstracts
January 1999
completed under conditions simulating the operation of the American Electric Power Tidd PFBC. The same test matrix, plus two tests using no sorbent, was completed with the Belle Ayr Powder River Basin subbituminous coal. 99100392
Determination
of oxidation
zone in mlned out
areas Xu, J. et al.
Proc. Annu. Int. Pittsburgh Coal Conf., 1997, 14, (l), 9-17. In spontaneous combustion of coal on mined out area quality and quantity the classification criteria of three zones are dealt with in this paper. The method for measuring intensity of wind leakage has then been given out. Moreover, the relationship among ventilation, gradient of wind pressure, quantity of wind leakage and scale of oxidation zone in mined out areas has also been investigated. Furthermore, put forward has been the empirical function for calculating the width of oxidation zone in mined out area.
Erosion/fatigue behaviour produced during in-situ gasification
99100393
of
solid
particles
Masudi, H. and Griffin, R. B. PD (Am. Sot. Mech. Eng.), 1996, 75, 265268. An alternative source of energy can be provided by the in-situ gasification of bituminous coal. The investigation of gasification products on metals has resulted in the conclusion that the degradation of materials is due to fatigue/erosion and corrosion effects. The fatigue damages are caused by repeated impact action of the rounded particles or properly oriented angular particles, resulting in the loss of materials in the form of platelets. Presented and discussed in this paper is information on solid particles produced during in-situ gasification of Texas lignite and their damages.
Experimental scrutiny equation of mesophase pitch
99100394
for
the
constltutlve
Wu, X. X. et al. Carbon, 1998, 36, (9), 1291-1298. Presented are the results of the detailed rheoloeical studv of four samoles of mesophase pitch (MP) in steady and oscillatoj shear flows. When pla’ced between a set of parallel plates the linear viscoelasticity of MP is characterized in a small-amplitude oscillatory shearing flow, and the nonlinear behaviour is examined by means of a steady shear flow. Determined from oscillatory experiments is the discrete viscoelastic spectrum of the MP. The ability of three differential non-linear constitutive equations the three constant Oldroyd, the non-linear Spriggs and the Meister models are tested for fitting the experimental data, and for describing the viscoelastic response of MP. The Spriggs and the Meister models are reasonably fit to the non-linear viscoelastic behaviour of MP. The discrete viscoelastic spectrum {a,. Xr,} is also appropriate for describing the linear viscoelasticity of MP. In addition, the temperature-time equivalence is applicable to the MPs.
Formation of carbon black as a byproduct of pyrolysis of light hydrocarbons in plasma jet
99100395
Chen, H.-G. et al. Proc. Annu. Int. Pittsburgh Coal Conf., 1997, 14, (7), 1215. in DC arc H2/Ar plasma jet at atmospheric The light hydrocarbons, pressure and at average temperatures between 1500 K and 4000 K, undergo complex reaction of flash hydropyrolysis. Acetylene is major product. Carbon black is bv-uroduct. CB is characterized by XRD, TEM, and adsorption-and-desorption of liquid nitrogen, respectively.
Hydration reaction chemistry associated with management of pressurized fluldlzed bed combustion ash
99100398
Bland, A. E. and Brown, T. H. Proc. Int. Conf. Fluid. Bed Combust., 1997, 14, (2), 683-692. The nature of the eeotechnical orooerties of the ash in ash management scenarios, such as odisposal and’ash re-use,, is directly controlled-by the chemical of the hydration of pressurized fluidtzed bed combustion (PFBC) ash. The ashes from PFBC technologies are distinctly different from those generated by atmospheric fluidized bed combustion (AFBC) technologies. Equilibrium conditions exist between sorbent calcination and recarbonation reactions at the pressures and temperatures typical of PFBC units, resulting in low free lime and high Ca carbonate contents in PFBC ash. In the laboratory, ashes from the AEP Tidd high-b bituminous coal-fired bubbling PFBC and the Karhula low-sulfur sub-bituminous coal-fired circulating PFBC pilot plant have been tested, in order to correlate the hydration reaction chemical to the observed geotechnical properties of strength and expansion. The study concluded that a number of hydration reactions, involving the formation of gypsum and ettringite are involved in the hydration chemical of PFBC ashes. The hydration reaction kinetics and final hydration products were shown to be dependent on ash characteristics, curing conditions and lime availability.
The Influence of mineral material upon the coking characteristics of coal
99100397
Radko, T. and Mianowski, A. Fuel, 1998, 77, (6), 503-507. At temperatures below 1073 K the conversion of coal into coke can be treated as two competitive processes which take place in two apparent areas of the kinetic and diffusion ranee. Modellina coal ovrolvsis usine conventional kinetic methods demo&rates this. TEe relatitk ariangemen? of these areas reflects the coking ability of individual coals. Upon the coking characteristics of the coals investigated the effect of the ash content can be evaluated using this kinetic-diffusion model.
By-products
related to fuels
99100385
Behavior of limestone as a H2S capture in stream gasification of coal Zhao, Z.-B. et al. Proc. Annu. Int. Pittsbumh Coal Conf., 1997, 14, (10). . I 13-18. The stream gasification of coal mixed with limestone has been investigated in a fluidized-bed reactor in order to determine whether CaCOs acts as a desulphurizing agent. The sulfur content in the coal used was 3.02 wt%. Coal with particle size of 0.21 mm and limestone with 0.125 mm are mixed and a series of limestone/coal mixtures is prepared, in which Ca/S molar ratio is 1.0, 2.0, 2.5, 3.5, 4.5 and 5.5. In the fluidized-bed reactor, the mixtures are heated to 1373 K in HrO-Nr atm and held at that temperature for 30 mm. The gas produced is collected from 573 K to 1373 K. Sulfur in gas samples and in residual solid is analysed. The experimental data establish that CaCOs reacts with HzS from product gas in gasification of coal with limestone. The reaction is strongly limited by both HzS pore diffusion in limestone and pore mouth plugging effect of CaS produced. The experimental results show that, when gasification temperature of coal is above 1123 K, CaS decomposability would increase with increase of steam content in fluidized-bed reactor.
nanotubes Carbon 99100388 pyrolysis of benzene
production
by
catalytic
Benito, A. et al. Carbon, 1998, 36, (5/6), 681-683. Different types of carbon nanostructures were generated by the pyrolysis of benzene at around 600-900°C over nickel powder, possessing a wide range of morphologies. The effects of temperature and time on carbon nanotubes growth were evaluated. The deposited carbon yield was measured, and the quality of the nanotubes was analysed by transmission electron microscopy (TEM). 99199387
Carbon single wall nanotubes elaboration
and
properties Bernier, P. et al. Carbon, 1998, 36, (5/6), 675-680. Interesting new molecules of the fullerene family are yielded by the coevaporation of carbon, in the presence of helium with some other element as catalyst, which have tubular morphologies with a cross-section at the nanoscale but lengths at the macroscale. Using nickel or cobalt based mixtures as catalyst with the electric arc technique, one obtains single wall carbon nanotubes in large quantities, with an average diameter of 1.4 nm and which assemble themselves in highly crystalline bundles containing a few tens of elements. X-ray and electron diffraction have been used to characterize the crystalline nature of individual bundles. The diameter dispersion has been studied in detail using Raman spectroscopy which shows impressively well-resolved structures of the observed modes. A majority of armchair tubes is observed, but some other configurations are also present with slightly different diameters. 99100388
Catalysts
and
method
for
synthetic
gas
production Kata, T. et al Jpn. Kokai Tokkyo Koho JP 10 174,869 [98 174,869] (Cl. BOlJ23/72), 30 Jun 1998, Appl. 96/338,283, 18 Dee 1996; 4 pp. (In Japanese) Copper is contained in the catalysts for manufacturing synthesis gas from di-Me ether and CO?. In synthesis gas manufacture, gas mixtures containing di-Me ether and CO2 are brought into contact with the catalysts. By using the catalysts at low temperature (200-500”) high-yield production of the gas (H and CO) is attained.
Catalysts, their manufacture, synthesis gas production
99199389
and their use in
Shikada, T. et al. Jpn. Kokai Tokkyo Koho JP 10 174,865 [98 174,865] (Cl. BOlJ23/44), 30 Jun 1998, Appl. 96/339,757, 19 Dee 1996; 6 pp. (In Japanese) In the manufacture of synthesis gas from d&Me ether and steam or COz,the catalysts use basic metal oxides which support palladium. The catalysts are manufactured by loading palladium on-the oxides and then treating the materials with aqueous basic solutions. In synthesis gas manufacture, gas mixtures containing di-Me ether and steam or COz are brought into contact with the catalysts. By using the catalysts at low temperature (200-600”) high-yield production of the gas (H and CO) is attained.
Catalytic synthesis of high-value chemicals and materials from coal
99100390
Song, C. and Schobert, H. H. Proc. Annu. Int. Pittsburgh Coal Conf., 1997, 14, (28), 17-32. A review was made on the production of chemical intermediates by selective catalytic conversion from coal derived feedstocks.
Characterization of hot-gas filter ash under PFBC 99/00391 operating conditions Henderson, A. K. et al. Proc. ht. Conf. Fluid. Bed Combust., 1997, 14, (2), 677-682. In this programme, the objective was to perform bench-scale dynamic tests of ash formation and long-term ash cake formation in pressurized fluidizedbed combustion (PFBC) systems to help in the development of methods to predict possible filter bridging problems and suggest possible strategies for mitigating these problems. During the programme, four ash formation tests using a washed coal from the Consol Enlow Fork mine, with two size distributions of Plum Run dolomite at two different temperatures, were
38
Fuel and Energy Abstracts
January 1999
completed under conditions simulating the operation of the American Electric Power Tidd PFBC. The same test matrix, plus two tests using no sorbent, was completed with the Belle Ayr Powder River Basin subbituminous coal. 99100392
Determination
of oxidation
zone in mlned out
areas Xu, J. et al.
Proc. Annu. Int. Pittsburgh Coal Conf., 1997, 14, (l), 9-17. In spontaneous combustion of coal on mined out area quality and quantity the classification criteria of three zones are dealt with in this paper. The method for measuring intensity of wind leakage has then been given out. Moreover, the relationship among ventilation, gradient of wind pressure, quantity of wind leakage and scale of oxidation zone in mined out areas has also been investigated. Furthermore, put forward has been the empirical function for calculating the width of oxidation zone in mined out area.
Erosion/fatigue behaviour produced during in-situ gasification
99100393
of
solid
particles
Masudi, H. and Griffin, R. B. PD (Am. Sot. Mech. Eng.), 1996, 75, 265268. An alternative source of energy can be provided by the in-situ gasification of bituminous coal. The investigation of gasification products on metals has resulted in the conclusion that the degradation of materials is due to fatigue/erosion and corrosion effects. The fatigue damages are caused by repeated impact action of the rounded particles or properly oriented angular particles, resulting in the loss of materials in the form of platelets. Presented and discussed in this paper is information on solid particles produced during in-situ gasification of Texas lignite and their damages.
Experimental scrutiny equation of mesophase pitch
99100394
for
the
constltutlve
Wu, X. X. et al. Carbon, 1998, 36, (9), 1291-1298. Presented are the results of the detailed rheoloeical studv of four samoles of mesophase pitch (MP) in steady and oscillatoj shear flows. When pla’ced between a set of parallel plates the linear viscoelasticity of MP is characterized in a small-amplitude oscillatory shearing flow, and the nonlinear behaviour is examined by means of a steady shear flow. Determined from oscillatory experiments is the discrete viscoelastic spectrum of the MP. The ability of three differential non-linear constitutive equations the three constant Oldroyd, the non-linear Spriggs and the Meister models are tested for fitting the experimental data, and for describing the viscoelastic response of MP. The Spriggs and the Meister models are reasonably fit to the non-linear viscoelastic behaviour of MP. The discrete viscoelastic spectrum {a,. Xr,} is also appropriate for describing the linear viscoelasticity of MP. In addition, the temperature-time equivalence is applicable to the MPs.
Formation of carbon black as a byproduct of pyrolysis of light hydrocarbons in plasma jet
99100395
Chen, H.-G. et al. Proc. Annu. Int. Pittsburgh Coal Conf., 1997, 14, (7), 1215. in DC arc H2/Ar plasma jet at atmospheric The light hydrocarbons, pressure and at average temperatures between 1500 K and 4000 K, undergo complex reaction of flash hydropyrolysis. Acetylene is major product. Carbon black is bv-uroduct. CB is characterized by XRD, TEM, and adsorption-and-desorption of liquid nitrogen, respectively.
Hydration reaction chemistry associated with management of pressurized fluldlzed bed combustion ash
99100398
Bland, A. E. and Brown, T. H. Proc. Int. Conf. Fluid. Bed Combust., 1997, 14, (2), 683-692. The nature of the eeotechnical orooerties of the ash in ash management scenarios, such as odisposal and’ash re-use,, is directly controlled-by the chemical of the hydration of pressurized fluidtzed bed combustion (PFBC) ash. The ashes from PFBC technologies are distinctly different from those generated by atmospheric fluidized bed combustion (AFBC) technologies. Equilibrium conditions exist between sorbent calcination and recarbonation reactions at the pressures and temperatures typical of PFBC units, resulting in low free lime and high Ca carbonate contents in PFBC ash. In the laboratory, ashes from the AEP Tidd high-b bituminous coal-fired bubbling PFBC and the Karhula low-sulfur sub-bituminous coal-fired circulating PFBC pilot plant have been tested, in order to correlate the hydration reaction chemical to the observed geotechnical properties of strength and expansion. The study concluded that a number of hydration reactions, involving the formation of gypsum and ettringite are involved in the hydration chemical of PFBC ashes. The hydration reaction kinetics and final hydration products were shown to be dependent on ash characteristics, curing conditions and lime availability.
The Influence of mineral material upon the coking characteristics of coal
99100397
Radko, T. and Mianowski, A. Fuel, 1998, 77, (6), 503-507. At temperatures below 1073 K the conversion of coal into coke can be treated as two competitive processes which take place in two apparent areas of the kinetic and diffusion ranee. Modellina coal ovrolvsis usine conventional kinetic methods demo&rates this. TEe relatitk ariangemen? of these areas reflects the coking ability of individual coals. Upon the coking characteristics of the coals investigated the effect of the ash content can be evaluated using this kinetic-diffusion model.