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Analysis of hydrocarbon mixtures by diffusion-ordered NMR spectroscopy
02 Liquid fuels (sources, properties, recover) combustion temperature around 850°C in the bed area, 600°C in the freeboard area, low oxygen concentrations in the flue gas and enough residence time for line particles in the freeboard.
Analysis of hydrocarbon mixtures by diffusionordered NMR spectroscopy
W/O0075
Kapur, G. S. et al. Fuel, 2000, 79, (11) 1347-1351. In the present work, utility of diffusion-ordered two-dimensional NMR spectroscopy (DOSY) has been demonstrated to analyse and assign the crowded NMR spectra of mixtures of hydrocarbons using ‘H- and 13Cdetected DOSY experiments. For the first time, a DOSY spectrum of a petroleum aromatic fraction is shown and assessed to illustrate the future applications of the technique for the analysis of such complex and heterogeneous molecular mixtures.
Application of a statistical technique to the production of ethanol from sugar beet molasses by Saccharomyces cerevisiae
W/O0076
Ergun, M. Ferda Mutlu, S. Bioresource Technology, 2000, 73, (3), 25l255. In this work, a statistical model which can be used to describe the rate of ethanol production from sugar beet molasses by Saccharomyces cerevisiae was develooed. Total sugar concentration. nH. and ammonium dihydrogen phosphate (NH4HzP04) concentration were chosen as a 23-factorial experimental design and the effects of these factors on ethanol production were examined in repeated shake flask cultures according to the Box-Wilson experimental design method. With the use of the develoned model a maximum ethanol oroduction of 1.06 g dm-’ h-’ was obtained when sugar concentratibn, pH, ammonium dihydrogen phosphate concentration, were 1.6 g dm-‘, 4.51, 0.72 g dmm3, respectively.
Application of model MIA-3 multifunction ion analyzer controlled by microprocessor - determination of thiol sulfur in distillate fuel by potentiometric titration
taken through Botryococcus alginites reveals a number of cellular features including: (i) micro-layering within resistant outer cell walls; (ii) preservation of resistant, very thin, outer walls of apical cells and (iii) stacks of successive thimble-shaoed lavers and funnel-shaoed CUDS which comprise the resistant stalk f;amework of fossilized cdmpoutid colonies. LSM also discloses preservation of pairs of ‘reproducing’ Botryococcus cells consisting of outer resistant walls enclosing mainly unstructured, granular organic matter in the ‘cell contents region’. Evidence provided by the serial images from these areas suggests that there is cellular organization and possible selective preservation of possible resistant biomacromolecules derived from aplanosphores or zoospores.
00100061 Contributions of aromatic conjunction and aromatic inner carbons to molar volume of polyaromatic hydrocarbons
Satou, M. er al. Fuel, 2000, 79, (9), 1057-1066. A modification of our previous equation for estimation of the molar volume of hydrocarbons on the basis of atomic group contributions was made to be able to extend the applicability to a wide variety of including condensed polyaromatic hydrocarbons hydrocarbons, (CPAHC), which are main components in heavy oils. Two atomic groups were additionally selected to characterize CPAHC, namely aromatic conjunction (ac) and aromatic inner (ai) carbons. Utilizing the molar volume data for pure CPAHC in literature, increments in the molar volume by the presence of the two groups were evaluated by a regression analysis as 2.8 and 8.6 ml/mol, respectively. The molar volumes of hydrocarbon mixtures in heavy oils containing CPAHC, estimated with the above increments, agree well with those observed. The equation is applicable to polyaromatic hydrocarbons with the ring numbers up to seven in both forms of pure substances and their mixtures.
00100077
Chen, Y. er al. Huaxue Chuanganqi, 1999, 19, (l), 6366. (In Chinese) A model MIA-3 multifunction ion analyser controlled by microprocessor coupled with model DAB-1B digital automatic burette was used for determining thiol sulfur in distillate fuel. The method can be used in the quick determination of thiol sulfur in gasoline, kerosene and diesel oil containing no HzS with results of a satisfactory standard.
Characterization of paraffin waxes by DSC and high temperature GC
W/O0076
Jayalakshmi, V. et al. Pet. Sci. Technol., 1999, 17, (7 & 8), 843-856. Differential scanning calorimetry (DSC) and high temperature capillary GC techniques were used to characterize paraffin waxes of different sources of crude oil. The carbon number distribution of the waxes were getermined by calibrating the GC with standard n-paraffins blend. The =H... transition obtained in DSC thermogram of the waxes were correlated with its normal paraffin content. This correlation was further validated by using the high temperature GC technique to obtain the n-paraffins content.
00100062 Correlations towards prediction of petroleum fraction viscosities: a semi-theoretical approach Ozdogan, S. Giirbiiz Yiicel, H. Fuel, 2000, 79, (IO), 1209-1214. A new semi-theoretical method based on Enskog’s hard sphere theory for dense fluids and the principle of corresponding states is presented for nredicting viscositv of petroleum fractions (Cs-Cts) at 40°C under atmospheric pressure: Viscosities, densities, normal boiling points and quantitative hydrocarbon analyses of 42 petroleum fractions were experimentally determined. The critical properties and the average molecular weights of the petroleum fractions were calculated by the Riazi Daubert equation. The predictions were compared with experimental data. Satisfactory results were obtained. The average error of the 42 uetroleum fractions could be decreased to less than 3.4%, utilising only density and average boiling point as input parameters. The addition of hydrocarbon group weight fractions as additional input parameters decrease the average error to around 2.6%. When acyclic rich and cyclic rich samples are handled separately, the average errors are below 2%.
Determination of aromatics and naphthenes in straight run gasoline by ‘H NMR spectroscopy. Part I
00/00063
Comparison of carbon rejection and hydrogen addition processes in production-upgrading complexes OO/WO79
Solari, R.B. et al. Proc. World Pet. Congr., 1998, 2, 945-946. At the Orinoco Belt in Venezuela, several strategic associations among PDVSA and major oil companies are currently underway to start heavy oil production and upgrading. The preferred process scheme in these associations is based on delayed coking. This paper discusses the advantages and disadvantages both from the technical and economic point of view, using delayed coking, as compared to hydroprocessing, in an integrated complex that includes production and upgradmg. Hydroconversion processes have the advantages of larger synthetic crude oil production at the same upgrader capacity, but require higher investment. However, in a market situation with high price differentials and cost of the raw material this investment would be fully rewarded.
Confocal laser scanning fluorescence microsco y of Botryococcus alginite from boghead oil shale, BoPtysk, Ukraine: selective preservation of various micro-algal components W/W060
Stasiuk, L. D. Org. Geochem., 1999, 30, (8B), 1021-1026. Confocal laser scanning fluorescence microscopy (LSM) has exceptional potential for resolving micrometer scale morphological details within fluorescing macerals, such as alginite, of hydrocarbon source rocks and oil shales. The aim of the investigation was to study the well preserved Botryococcus alginites from a Paleogene boghead oil shale from central Ukraine. The results clearly illustrates that. LSM can effectively resolve microalgal cellular organization. A dominance of highly resistant, outermost cell walls in Botryococcus confirms that selective preservation was an effective process during kerogen formation. Three dimensional serial section compilations of images
Kapur, G. S. er al. Fuel, 2000, 79, (9), 1023-1029. A H NMR-based method has been developed for determining the composition (aromatics, naphthenes and paraffins) of straight run gasoline fractions. The equations required for the calculations have been derived based on the assignment of the overlapped ‘H NMR spectra of the samples with particular emphasis on signals from naphthenes and iso-paraffins. The ‘H NMR results have been compared with those- obtained from a gas chromatography (GC) method. The absolute standard deviations between the NMR and GC methods are 1.7 and 2.1% for total aromatics and naphthenes, respectively.
Development of a model s stem to study fuel autoxidation in supercritical media: cyecomposition kinetics of 2,2’-azobis(isobutyronitrile) in supercritical carbon dioxide
00/00064
Morris, R. E. et a/. Fuel, 2000, 79, (9), 1101-1107. A high pressure reactor has been constructed and used for in siru spectroscopic measurements of reaction kinetics in supercritical fluids. The thermal decomposition of 2,2’-azobis(isobutyronitrile) (AIBN) in supercritical carbon dioxide (SC-CO*) was studied as part of an effort to characterize free-radical autoxidation of hvdrocarbon fuels under supercritical conditions. The findings show that AIBN decomposes both thermally and photochemically in SC-CO2 to form the 2-cyano-2propyl free radical which dimerizes to form tetramethylsuccinic dinitrile and dimethyl-N-(2-cyano-2-propyl) ketenimine. Examination of the decomposition kinetics of the ketenimine revealed that it was photochemically stable in the kinetic reactor, but decomposed thermally to form the dinitrile.
Fuel and Energy Abstracts
January 2001
9
Analysis of hydrocarbon mixtures by diffusionordered NMR spectroscopy
W/O0075
Kapur, G. S. et al. Fuel, 2000, 79, (11) 1347-1351. In the present work, utility of diffusion-ordered two-dimensional NMR spectroscopy (DOSY) has been demonstrated to analyse and assign the crowded NMR spectra of mixtures of hydrocarbons using ‘H- and 13Cdetected DOSY experiments. For the first time, a DOSY spectrum of a petroleum aromatic fraction is shown and assessed to illustrate the future applications of the technique for the analysis of such complex and heterogeneous molecular mixtures.
Application of a statistical technique to the production of ethanol from sugar beet molasses by Saccharomyces cerevisiae
W/O0076
Ergun, M. Ferda Mutlu, S. Bioresource Technology, 2000, 73, (3), 25l255. In this work, a statistical model which can be used to describe the rate of ethanol production from sugar beet molasses by Saccharomyces cerevisiae was develooed. Total sugar concentration. nH. and ammonium dihydrogen phosphate (NH4HzP04) concentration were chosen as a 23-factorial experimental design and the effects of these factors on ethanol production were examined in repeated shake flask cultures according to the Box-Wilson experimental design method. With the use of the develoned model a maximum ethanol oroduction of 1.06 g dm-’ h-’ was obtained when sugar concentratibn, pH, ammonium dihydrogen phosphate concentration, were 1.6 g dm-‘, 4.51, 0.72 g dmm3, respectively.
Application of model MIA-3 multifunction ion analyzer controlled by microprocessor - determination of thiol sulfur in distillate fuel by potentiometric titration
taken through Botryococcus alginites reveals a number of cellular features including: (i) micro-layering within resistant outer cell walls; (ii) preservation of resistant, very thin, outer walls of apical cells and (iii) stacks of successive thimble-shaoed lavers and funnel-shaoed CUDS which comprise the resistant stalk f;amework of fossilized cdmpoutid colonies. LSM also discloses preservation of pairs of ‘reproducing’ Botryococcus cells consisting of outer resistant walls enclosing mainly unstructured, granular organic matter in the ‘cell contents region’. Evidence provided by the serial images from these areas suggests that there is cellular organization and possible selective preservation of possible resistant biomacromolecules derived from aplanosphores or zoospores.
00100061 Contributions of aromatic conjunction and aromatic inner carbons to molar volume of polyaromatic hydrocarbons
Satou, M. er al. Fuel, 2000, 79, (9), 1057-1066. A modification of our previous equation for estimation of the molar volume of hydrocarbons on the basis of atomic group contributions was made to be able to extend the applicability to a wide variety of including condensed polyaromatic hydrocarbons hydrocarbons, (CPAHC), which are main components in heavy oils. Two atomic groups were additionally selected to characterize CPAHC, namely aromatic conjunction (ac) and aromatic inner (ai) carbons. Utilizing the molar volume data for pure CPAHC in literature, increments in the molar volume by the presence of the two groups were evaluated by a regression analysis as 2.8 and 8.6 ml/mol, respectively. The molar volumes of hydrocarbon mixtures in heavy oils containing CPAHC, estimated with the above increments, agree well with those observed. The equation is applicable to polyaromatic hydrocarbons with the ring numbers up to seven in both forms of pure substances and their mixtures.
00100077
Chen, Y. er al. Huaxue Chuanganqi, 1999, 19, (l), 6366. (In Chinese) A model MIA-3 multifunction ion analyser controlled by microprocessor coupled with model DAB-1B digital automatic burette was used for determining thiol sulfur in distillate fuel. The method can be used in the quick determination of thiol sulfur in gasoline, kerosene and diesel oil containing no HzS with results of a satisfactory standard.
Characterization of paraffin waxes by DSC and high temperature GC
W/O0076
Jayalakshmi, V. et al. Pet. Sci. Technol., 1999, 17, (7 & 8), 843-856. Differential scanning calorimetry (DSC) and high temperature capillary GC techniques were used to characterize paraffin waxes of different sources of crude oil. The carbon number distribution of the waxes were getermined by calibrating the GC with standard n-paraffins blend. The =H... transition obtained in DSC thermogram of the waxes were correlated with its normal paraffin content. This correlation was further validated by using the high temperature GC technique to obtain the n-paraffins content.
00100062 Correlations towards prediction of petroleum fraction viscosities: a semi-theoretical approach Ozdogan, S. Giirbiiz Yiicel, H. Fuel, 2000, 79, (IO), 1209-1214. A new semi-theoretical method based on Enskog’s hard sphere theory for dense fluids and the principle of corresponding states is presented for nredicting viscositv of petroleum fractions (Cs-Cts) at 40°C under atmospheric pressure: Viscosities, densities, normal boiling points and quantitative hydrocarbon analyses of 42 petroleum fractions were experimentally determined. The critical properties and the average molecular weights of the petroleum fractions were calculated by the Riazi Daubert equation. The predictions were compared with experimental data. Satisfactory results were obtained. The average error of the 42 uetroleum fractions could be decreased to less than 3.4%, utilising only density and average boiling point as input parameters. The addition of hydrocarbon group weight fractions as additional input parameters decrease the average error to around 2.6%. When acyclic rich and cyclic rich samples are handled separately, the average errors are below 2%.
Determination of aromatics and naphthenes in straight run gasoline by ‘H NMR spectroscopy. Part I
00/00063
Comparison of carbon rejection and hydrogen addition processes in production-upgrading complexes OO/WO79
Solari, R.B. et al. Proc. World Pet. Congr., 1998, 2, 945-946. At the Orinoco Belt in Venezuela, several strategic associations among PDVSA and major oil companies are currently underway to start heavy oil production and upgrading. The preferred process scheme in these associations is based on delayed coking. This paper discusses the advantages and disadvantages both from the technical and economic point of view, using delayed coking, as compared to hydroprocessing, in an integrated complex that includes production and upgradmg. Hydroconversion processes have the advantages of larger synthetic crude oil production at the same upgrader capacity, but require higher investment. However, in a market situation with high price differentials and cost of the raw material this investment would be fully rewarded.
Confocal laser scanning fluorescence microsco y of Botryococcus alginite from boghead oil shale, BoPtysk, Ukraine: selective preservation of various micro-algal components W/W060
Stasiuk, L. D. Org. Geochem., 1999, 30, (8B), 1021-1026. Confocal laser scanning fluorescence microscopy (LSM) has exceptional potential for resolving micrometer scale morphological details within fluorescing macerals, such as alginite, of hydrocarbon source rocks and oil shales. The aim of the investigation was to study the well preserved Botryococcus alginites from a Paleogene boghead oil shale from central Ukraine. The results clearly illustrates that. LSM can effectively resolve microalgal cellular organization. A dominance of highly resistant, outermost cell walls in Botryococcus confirms that selective preservation was an effective process during kerogen formation. Three dimensional serial section compilations of images
Kapur, G. S. er al. Fuel, 2000, 79, (9), 1023-1029. A H NMR-based method has been developed for determining the composition (aromatics, naphthenes and paraffins) of straight run gasoline fractions. The equations required for the calculations have been derived based on the assignment of the overlapped ‘H NMR spectra of the samples with particular emphasis on signals from naphthenes and iso-paraffins. The ‘H NMR results have been compared with those- obtained from a gas chromatography (GC) method. The absolute standard deviations between the NMR and GC methods are 1.7 and 2.1% for total aromatics and naphthenes, respectively.
Development of a model s stem to study fuel autoxidation in supercritical media: cyecomposition kinetics of 2,2’-azobis(isobutyronitrile) in supercritical carbon dioxide
00/00064
Morris, R. E. et a/. Fuel, 2000, 79, (9), 1101-1107. A high pressure reactor has been constructed and used for in siru spectroscopic measurements of reaction kinetics in supercritical fluids. The thermal decomposition of 2,2’-azobis(isobutyronitrile) (AIBN) in supercritical carbon dioxide (SC-CO*) was studied as part of an effort to characterize free-radical autoxidation of hvdrocarbon fuels under supercritical conditions. The findings show that AIBN decomposes both thermally and photochemically in SC-CO2 to form the 2-cyano-2propyl free radical which dimerizes to form tetramethylsuccinic dinitrile and dimethyl-N-(2-cyano-2-propyl) ketenimine. Examination of the decomposition kinetics of the ketenimine revealed that it was photochemically stable in the kinetic reactor, but decomposed thermally to form the dinitrile.
Fuel and Energy Abstracts
January 2001
9