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Production and characterization of activated carbon from a bituminous coal by chemical activation
D Cuhadaroglu, OA Uygun
African Journal of Biotechnology , 2008,
Abstract: In this study, the use of a bituminous coal for the production of activated carbons with chemical activation was investigated. The effects of process variables such as chemical reagents, activation temperature, impregnation ratio and carbonization temperature were investigated to optimize these parameters. The resultant activated carbons were characterized in terms of iodine number, BET surface area, and total and micropore volumes. Acidic surface groups were established by Fourier Transmittance Infrared Spectroscopy (FTIR) technique.
A TG-FTIR study on catalytic pyrolysis of coal
应用TG-FTIR联用研究催化剂对煤热解的影响

YANG Jing-biao,CAI Ning-sheng,
杨景标
,蔡宁生

燃料化学学报 , 2006,
Abstract: The catalytic effects of alkali, alkaline earth and transition metals on pyrolysis of lignite and bituminous coals were investigated using TG-FTIR. The results indicate that the orders of catalytic effects on the pyrolysis of lignite and bituminous coals are Ni ~ Fe ~ Ca ~ K and Ca ~ Fe > Ni > K, respectively. The maximal increments of conversion for the lignite and the bituminous coal are 10.1% and 6.4% with catalysts loaded. The CH4 yield of the bituminous coal is larger than that of the lignite. The increase in yield of CO2, H2O, CH4, and CO is dependent on the catalysts, which are closely related to the temperature region and coal ranks.
Composition of bituminous coal in dependence on environment and temperature of alteration  [PDF]
Kurková M,Klika Z,Martinec P,Pěg?imo?ová J
Bulletin of Geosciences , 2003, DOI: 10.3140/bull.geosci.2003.01.023
Abstract: Bituminous coal from the proximity of red beds bodies of the Upper Silesian Coal Basin was altered by oxidation and thermally altered. This naturally altered coal was compared with laboratory-altered coal samples prepared at various temperatures and time, in oxidative and inert atmosphere, with weathered coal and with natural cokes. Comparison of samples was performed using coal petrographic and chemical analyses of individual coal samples.
The Tropical Forest and Fire Emissions Experiment: method evaluation of volatile organic compound emissions measured by PTR-MS, FTIR, and GC from tropical biomass burning
T. G. Karl, T. J. Christian, R. J. Yokelson, P. Artaxo, W. M. Hao,A. Guenther
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2007,
Abstract: Volatile Organic Compound (VOC) emissions from fires in tropical forest fuels were quantified using Proton-Transfer-Reaction Mass Spectrometry (PTRMS), Fourier Transform Infrared Spectroscopy (FTIR) and gas chromatography (GC) coupled to PTRMS (GC-PTR-MS). We investigated VOC emissions from 19 controlled laboratory fires at the USFS (United States Forest Service) Fire Sciences Laboratory and 16 fires during an intensive airborne field campaign during the peak of the burning season in Brazil in 2004. The VOC emissions were dominated by oxygenated VOCs (OVOC) (OVOC/NMHC ~4:1, NMHC: non-methane hydrocarbons) The specificity of the PTR-MS instrument, which measures the mass to charge ratio of VOCs ionized by H3O+ ions, was validated by gas chromatography and by intercomparing in-situ measurements with those obtained from an open path FTIR instrument. Emission ratios for methyl vinyl ketone, methacrolein, crotonaldehyde, acrylonitrile and pyrrole were measured in the field for the first time. Our measurements show a higher contribution of OVOCs than previously assumed for modeling purposes. Comparison of fresh (<15 min) and aged (>1 h–1 d) smoke suggests altered emission ratios due to gas phase chemistry for acetone but not for acetaldehyde and methanol. Emission ratios for numerous, important, reactive VOCs with respect to acetonitrile (a biomass burning tracer) are presented.
The tropical forest and fire emissions experiment: method evaluation of volatile organic compound emissions measured by PTR-MS, FTIR, and GC from tropical biomass burning  [PDF]
T. G. Karl,T. J. Christian,R. J. Yokelson,P. Artaxo
Atmospheric Chemistry and Physics Discussions , 2007,
Abstract: Volatile Organic Compound (VOC) emissions from fires in tropical forest fuels were quantified using Proton-Transfer-Reaction Mass Spectrometry (PTRMS), Fourier Transformation Infrared Spectroscopy (FTIR) and gas chromatography (GC) coupled to PTRMS (GC-PTR-MS). We investigated VOC emissions from 19 controlled laboratory fires at the USFS Fire Sciences Laboratory and 16 fires during an intensive airborne field campaign during the peak of the burning season in Brazil in 2004. The VOC emissions were dominated by oxygenated VOCs (OVOC) (OVOC/NMHC ~4:1, NMHC: non-methane hydrocarbons) The specificity of the PTR-MS instrument, which measures the mass to charge ratio of VOCs ionized by H3O+ ions, was validated by gas chromatography and by intercomparing in-situ measurements with those obtained from an open path FTIR instrument. Emission ratios for methyl vinyl ketone, methacrolein, crotonaldehyde, acrylonitrile and pyrrole were measured in the field for the first time. Our measurements show a higher contribution of OVOCs than previously assumed for modeling purposes. Comparison of fresh (<15 min) and aged (>1hour-1day) smoke suggests altered emission ratios due to gas phase chemistry for acetone but not for acetaldehyde and methanol. Emission ratios for numerous, important, reactive VOCs with respect to acetonitrile (a biomass burning tracer) are presented.
The Tropical Forest and Fire Emissions Experiment: method evaluation of volatile organic compound emissions measured by PTR-MS, FTIR, and GC from tropical biomass burning
T. G. Karl,T. J. Christian,R. J. Yokelson,P. Artaxo
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2007,
Abstract: Volatile Organic Compound (VOC) emissions from fires in tropical forest fuels were quantified using Proton-Transfer-Reaction Mass Spectrometry (PTRMS), Fourier Transform Infrared Spectroscopy (FTIR) and gas chromatography (GC) coupled to PTRMS (GC-PTR-MS). We investigated VOC emissions from 19 controlled laboratory fires at the USFS (United States Forest Service) Fire Sciences Laboratory and 16 fires during an intensive airborne field campaign during the peak of the burning season in Brazil in 2004. The VOC emissions were dominated by oxygenated VOCs (OVOC) (OVOC/NMHC ~4:1, NMHC: non-methane hydrocarbons) The specificity of the PTR-MS instrument, which measures the mass to charge ratio of VOCs ionized by H3O+ ions, was validated by gas chromatography and by intercomparing in-situ measurements with those obtained from an open path FTIR instrument. Emission ratios for methyl vinyl ketone, methacrolein, crotonaldehyde, acrylonitrile and pyrrole were measured in the field for the first time. Our measurements show a higher contribution of OVOCs than previously assumed for modeling purposes. Comparison of fresh (<15 min) and aged (>1 h–1 d) smoke suggests altered emission ratios due to gas phase chemistry for acetone but not for acetaldehyde and methanol. Emission ratios for numerous, important, reactive VOCs with respect to acetonitrile (a biomass burning tracer) are presented.
MODELING OF BITUMINOUS COAL AND LEAN COAL COMBUSTION IN A COMBUSTOR OF CO-FLOWING JETS WITH LARGE VELOCITY DIFFERENCE
大速差射流燃烧室中烟煤与贫煤燃烧的数值模拟

Zhang Jian Zhou Lixing,
张健
,周力行

力学学报 , 1990,
Abstract: The two-dimensional turbulent re irculating two-phase flow, mixing ancl combustion in a combustor of coflowing jets with large velocity difference for two types of pulverized coal-bituminous coal and lean coal are predicted by the trajectory model of particle phase with some improvements in the solution technique. The prediction results show the particle motion pattern and the mixing of the particles with the reverse gas flow. The stabilization of pulverized coal fla.ne is realized mainly by volatile combustion in the central recirculation zone. The cold gas flow prediction is in good agreement with the experimental data.
Characterization of Aluminum(III) Complexes in Coal Organic Matter  [PDF]
Pavel Straka
American Journal of Analytical Chemistry (AJAC) , 2016, DOI: 10.4236/ajac.2016.74036
Abstract: For geochemical purposes, complex aluminum compounds in coal organic matter in different types of coal were identified by solid state nuclear magnetic resonance measurements of 27Al. Low ash samples of anthracites, bituminous coals and altered coals from the Czech Republic, Russia, Ukraine, China and Australia were tested; further, low ash lignite and xylite from the Czech Republic and gagatite from Poland were analyzed. In acquired 27Al MAS NMR spectra, two significant peaks at chemical shifts were recorded, at 3.5 - 4 and 13.5 - 15 ppm. It was found that the significant peak at chemical shift at 3.5 - 4 ppm in spectra of bituminous coals, lignite, gagatite and a thermally weakly altered coal corresponds to that obtained for triaquo-hydroxo-diphenoxido-Aluminum(III) complex. The existence of triaquo-triphenoxido-Aluminum(III) complex in the spec- tra of anthracites, some bituminous coals and another thermally altered coal can be approved by the chemical shift at 13.5 - 15 ppm. These findings indicate that at least two different Al complexes were identified in coal organic matter. Further it was found that these complexes are concentrated in vitrinite fraction (alicyclic-aromatic part of coal), notably in collotelinite (gelified and homogenous vitrinite constituent). Ways of Al complexes formation in coal are suggested and their thermal stability is discussed.
Organic sulphur as a main index for determining the genetic type of low-rank coals  [PDF]
Butuzova L,Bechtel A,Turchanina O,Safin V A
Bulletin of Geosciences , 2005, DOI: 10.3140/bull.geosci.2005.01.003
Abstract: A statistical analysis of the quality of Donetz low-rank coals has been carried out using catalogue data and freshly-sampled coals. Thirty seven samples of bituminous coals with volatile matter contents ranging from 37.2% to 44.2% were used. All coals are closely clustered into groups of samples with different ranges of (O+N) daf/Cdaf atomic ratio. It has been shown that linear correlations exist between the S daf and S daf/Cdaf ratio and Vdaf. The correlation coefficients within the different sample groups have been found to be r1=0.87; r2=0.92, and r3=0.98. They increase as the Odaf/Cdaf interval is narrowed down, i.e. as the coal rank is more exactly defined. Similarly, a statistical dependence between the volatile matter yield and the organic sulphur content has been found for the Donetsk DG and G brand coals, with the correlation coefficients being r = 0.91 and r = 0.95, respectively. It was also found that some structural parameters of the coals correlate with Sodaf.
Characterization of Size and Density Separated Fractions of a Bituminous Coal as a Feedstock for Entrained Slagging Gasification  [PDF]
Nari Soundarrajan, Nandakumar Krishnamurthy, Sarma V. Pisupati
International Journal of Clean Coal and Energy (IJCCE) , 2013, DOI: 10.4236/ijcce.2013.24007
Abstract: Coal is one of the main sources of energy in many parts of the world and has one of the largest reserves/production ratios amongst all the non-renewable energy sources. Gasification of coal is one among the advanced technologies that has potential to be used in a carbon constrained economy. However, gasification availability at several commercial demonstrations had run into problems associated with fouling of syngas coolers due to unpredictable flyash formation and unburnt carbon losses. Computer models of gasifiers are emerging as a powerful tool to predict gasifier performance and reliability, without expensive testing. Most computer models used to simulate gasifiers tend to model coal as a homogenous entity based on bulk properties. However, coal is a heterogeneous material and comminution during feedstock preparation produces particle classes with different physical and chemical properties. It is crucial to characterize the heterogeneity of the feedstocks used by entrained flow gasifiers. To this end, a low ash US bituminous coal that could be used as a gasifier feedstock was segregated into density and size fractions to represent the major mineral matter distributions in the coal. Float and sink method and sieving were employed to partition the ground coal. The organic and inorganic content of all density fractions was characterized for particle size distribution, heating value, ultimate analysis, proximate analysis, mineral matter composition, ash composition, and petrographic components, while size fractions were characterized for heating value, ash composition, ultimate and proximate analysis. The proximate, ultimate and high heating value analysis showed that variation in these values is limited across the range of size fractions, while the heterogeneity is significant over the range of density fractions. With respect to inorganics, the mineral matter in the heavy density fractions contribute significantly to the ash yield in the coal while contributing very little to its heating value. The ash yield across the size fractions exhibits a bimodal distribution. The heterogeneity is also significant with respect to the base-to-acid ratio across the size and density fractions. The results indicate that the variations in organic and inorganic content over a range of density and size classes are significant, even in the low ash, vitrinite rich coal sample characterized here. Incorporating this information appropriately into particle population models used in gasifier simulations will significantly enhance their accuracy of performance predictions.
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