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Alkanes from Fischer-Tropsch product

Possible inter relationships of natural substances are important. Similarities of the low molecular weight alkane isomers from crude oil and Fischer-Tropsch synthesis product have been reported. A similar composition for high temperature coal carbonization has been found. The C4 to C7 alkane isomers from these sources can be calculated quantitatively with equations developed for Fischer-Tropsch products. A reversal of the concentrations of the monomethyl isomers from CG (2 Me > 3 Me) to C7 (3 Me > 2 Me) occurs in all three products comparisons at higher carbon numbers indicate some dissimilarities. Naphthene isomers for crude oil and high temperature coal carbonization also have similar compositions. Aliphatic hydrocarbons from low temperature coal processes are considerably different. The C1 isotopic composition of pure compounds from the various sources are being compared in order to provide information on their origin. [Pg.38]

The data recently published by Ouchi and Imuta (15) on a chloroform extract of Yubari coal also indicates similarities to petroleum. Branching is greater at the low carbon numbers and drops off at higher carbon numbers as in crudes (II) and Fischer-Tropsch product (17). The other similarity to crude oil is noted in the odd-even alternation of normal alkanes from Cm to C25 with the odd carbon number alkanes predominating. [Pg.42]

Other data on analyses of coal products have been given by Girling (9). A list of alkanes found, but not quantitatively determined, from C through C7, indicates that the normals and monomethyl isomers predominate. This again is similar to crude oil and Fischer-Tropsch product. [Pg.42]

Because of decomposition problems of Rh catalysts during the separation of high-boiling products, most commercial plants for long-chain aldehydes (>Cjo) operate with Co catalysts. These approaches are based on unmodified catalysts under rather severe conditions (30 MPa, 200 C) [59]. Besides alcohols, alkanes are also formed. Through modification of the Co catalyst with phosphines, the pressure can be lowered (<10MPa) and, as a result, selectivity toward the formation of the linear alcohols is enhanced [60]. A suitable feedstock of higher olefins (up to C20) can be derived from Fischer-Tropsch feed (Sasol), or it is produced by SHOP. Products are commonly used for the production of surfactant alcohols. [Pg.293]

Considerable attention has been paid to the application of CNTs as the catalyst support for Fischer Tropsch synthesis (FTS), mainly driven by utilization of the confinement effect (Section 15.2.3). In general, this process is a potential alternative to synthesize fuel (alkanes) or basic chemicals like alkenes or alcohols from syngas, which can be derived from coal or biomass. The broad product spectrum, which can be controlled only to a limited extent by the catalyst, prohibited its industrial realization so far, however, it is considered an important building block for future energy and chemical resource management based on renewables. [Pg.419]

Moreover, alkanes can also be produced from the reaction of reforming products, H2 and CO/CO2, via methanation and Fischer-Tropsch processes. [Pg.216]

There are very few data available on alkane isomers above C7 for comparison of petroleum or any other natural product. Some analyses, however, are available for the Cs isomers from alkanes from crude oils. Predicted results from the Fischer-Tropsch equation with / = 0.1 are given in Table II along with analyses of Cs alkanes from two crude oils (2, 4). A very definite exception to the predicted values appears in Table I, namely, the predominance of 2-methylheptane over 3-methylheptane. This observation is contrary to the prediction of the equation. According to scheme B (1) other Ck analyses from crudes made available to the author by M. J, O Neal show the same predominance cf the 2-methyl isomers. A total of four Ch analyses available for comparison represent crudes from western and southwestern United States. As mentioned in (8), 11 out of 14 analyses through the Ct s showed the reversal the three that did not have the predicted reversal also came from the Southwest. It would be of interest to have analyses of Cs s in crudes from other parts of the world in order to study this reversal. For Cn alkanes only partial analyses are available they are Ponca City, Okla. crude (4) and a commercial mixture... [Pg.39]

Coal Derivatives. In attempting to extend this investigation to coal products, it was evident that not many isomeric analyses have been carried out. In the case of low temperature tar the predominant species reported have been normal olefins and normal alkanes. Branched alkane isomers are probably very low in concentration. However, limited data for high temperature coal tar (10) and for coal hydrogenation products (7, 12) indicate a close comparison of C7 alkanes with those from crude oil and the values predicted by the Fischer-Tropsch equation (Table III, top). A close comparison is notable also in the bottom part of Table III, which gives data for the Co and C7 naphthenes from high temperature coal carbonization, coal hydrogenation, and a crude oil. [Pg.42]

Fischer-Tropsch (FT) technology converts synthesis gas produced by reforming of methane or coal gasification into waxy products. Long alkanes (-CH2 -chains) produced by using FT synthesis are chemically similar to polyethylene. Lubricating oils derived from isomerization of FT waxes are gaining interest due to increased demand for lubricants with the advanced performance and environmental benefits described earlier. [Pg.351]

The CO/H2 gas (also called water-gas) - depending on the CO H2 ratio - can also be converted (using the Fischer-Tropsch synthesis) to alkanes, alkenes and alcohols. Preferably, substances should be generated for application in known technical systems such as liquefied petroleum gas or low pressure gas (LPG) and gasoline as well as natural gas. The production of solar substitutes for diesels and oils (C > 8), that is petrol products from the fractional distillation of crude oil between 200 °C and 350 °C, is also possible, but offers no advantages in the solar fuel cycle and its stepwise replacement by gases and gasoline should be foreseen. [Pg.319]

Most organic commodity chemicals are currently made commercially from ethylene, a product of oil refining. In the next several decades, we may see a shift toward other carbon sources for these chemicals. Either coal or natural gas (CH4) can be converted with steam into CO/H2 mixtures called water-gas or synthesis gas and then on to methanol or to alkane fuels with various heterogeneous catalysts (Eq. 12.19). In particular, the Fischer-Tropsch reaction converts synthesis gas to a mixture of long-chain alkanes and alcohols using heterogeneous catalysis. [Pg.332]

From Figure 11.8, it can be seen that Alkane, is produced from biomass in the conversion pathway sequence of pyrolysis and Fischer-Tropsch processes 1 and 2 followed by fractional distillation of alkanes, which are all thermochemical pathways. It is worth pointing out that specific separation processes that suit the identified product can be chosen and included in the integrated biorefinery to refine and separate the final product from by-products. Hence, separation processes for alkanes are chosen based on the results of the product design identified in stage 1 of the methodology. The performance of the separation processes is then taken into consideration in identifying the product yield and economic potential of the overall conversion pathway. [Pg.293]


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See also in sourсe #XX -- [ Pg.32 , Pg.35 ]




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