Coal, alkanes from

FRICDCL AND SHARKBY Alkanes from Coal, Petroleum, and Gas 33... 

FRIEDEL AND SHARKEY Alkane from Coal, Potroloum, and Gas 35... 

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. 

Petroleum became the primary source of hydrocarbons for chemical feedstocks, beginning in about 1850 with the discovery of easily extracted cmde oil in eastern Pennsylvania and in the Ural mountains of Russia. The gases from the primary distillation of cmde oil and the light products from FCC, catalyticfreforming, and hydroprocessing are ideal mixtures of C2 to Cg alkanes that can be used to make many chemicals. Petroleum products are also cleaner than those from coal, producing no ash and less sulfur. 

Benzene, naphthalene, toluene, and the xylenes are naturally occurring compounds obtained from coal tar. Industrial synthetic methods, called catalytic reforming, utilize alkanes and cycloalkanes isolated from petroleum. Thus, cyclohexane is dehydrogenated (aromatization), and n-hexane(cycli> zation) and methylcyclopentane(isomerization) are converted to benzene. Aromatization is the reverse of catalytic hydrogenation and, in the laboratory, the same catalysts—Pt, Pd, and Ni—can be used. The stability of the aromatic ring favors dehydrogenation. 

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. 

Natural Gas. A search has also been made for data on alkane isomers from natural gas. So far the search has been very unsuccessful. Only one isomeric analysis has been found. This was provided by Duane Kniebes of the Institute of Gas Technology and is shown in Table IV. Comparison of natural gas data with those found in crude oil and in predictions of the Fischer-Tropsch equation is not very good, particularly in the Oz s. It is hoped that better data will be forthcoming both from natural gas and from coal. In the search for natural gas data, at least one company contacted has decided that its research department should obtain isomeric data on many natural gases. 

Dr. Friedel. No. Products of the pyrolysis of coal under high temperature carbonization conditions surely must arise from degradation. The quantitative prediction of C7 alkane isomers from coal may possibly indicate a relationship in compositions of coal and petroleum. The hydrocarbons from each perhaps should be similar since both are supposedly derived from organic plants ... 

The history of the oxo reaction is also noteworthy. It was developed originally in Germany in the years following World War 1. At that time, the German chemical industry was faced with inadequate supplies of petroleum. Many German chemists therefore turned to research on ways by which hydrocarbons could be synthesized from smaller building blocks, particularly carbon monoxide and hydrogen derived from coal. The success achieved was remarkable and led to alkane and alkene syntheses known as the Fischer-Tropsch process ... 

Catty acids are widely distributed in nature and have been studied extensively in petroleum (1, 2) and sediments (1, 3, 4, 5), as well as in living organisms (6, 7, 8). Fatty acids are major components in most living organisms, and since they are geochemically quite stable (9), they are important components in most depositional environments. The presence of fatty acids in coals has been recorded (10, 11, 12), but there appears to be little published information available on their distribution, particularly in brown coals, except in montan wax deposits (13, 14). In contrast, the distribution of n-alkanes in coals has been widely studied, and the maxima of the distributions have been shown to range from C29... 

Just where do the enormous quantities of simple aromatic compounds come from There are two large reservoirs of organic material, coal and petroleum, and aromatic compounds are obtained from both. Aromatic compounds are separated as such from coal tar, and are synthesized from the alkanes of petroleum. 

In general, jet fuels from shale oil have the highest and those from coal the lowest n-alkane content. The origin of these n-alkanes in the amounts observed, especially in shale derived fuels, is not readily explained on the basis of literature information. Studies of the processes, particularly the... 

Over the last two decades, developments in G.C., mass spectrometry (M.S.), N.M.R. spectroscopy and other physical techniques have appreciably extended the ability of chemists to undertake detailed analyses of fractions extracted from coal and other fossil fuels. In this paper, we survey some of the characterization techniques for alkanes, emphasising particularly... 

Ti measurements at normal probe temperatiire were made by the inversion-recovery Fourier-transform (IRFT) technique on deuteriated chloroform solutions of pristane (2,6,10,1 i -tetra-methylpentadecane) and of branched-chain/cyclic alkanes from Rexco coal tar and a Turkish asphaltite (Avgamasya). Inversion-recovery traces were recorded by using 200 cycles of the l80°-90°-PD pulse sequence with a pulse delay time (PD) of about 20s at a series of intervals, T (e.g. 1,3,5s, Figure 3). Ti values ( 0.5s) (Table IV) were measiired by plotting In(AQ-A) vs. T, where A is the equilibrium amplitude in a normal FT spectrum and A is the amplitude in an IRFT spectrum (Figure k). 

In more specific terms, alkanes can be extracted from coal(s) by a mixture of hot benzene and ethanol over a period of 250 h. The alkanes are actually isolated from the extract by adsorption chromatography and those alkanes that have received considerable attention are that portion which... 

The liquid phase carbonization process can be categorized on the basis of the starting material alkane hydrocarbon, alkene hydrocarbon, aromatic hydrocarbon, and PAH. Consequently, the primary material for MCMBs typically contains a large amount of PAHs from coal pitch and heavy oil. Components in primary materials, such as pyridine insolubles (Pis), quinoline insolubles (QIs), and other additives, and reaction conditions affect the growth, formation, and structure of MCMBs. 

A common colorless and flammable gas at room temperature and pressure, propene is generally produced from coal or petroleum and is a nonrenewable resource. However, it can be used in combination with hydrogen peroxide (H Oj) and employed as an inexpensive rocket fuel propellant. Alkenes can also form branched compounds, just as the alkanes (Figure 4.11). However, in the case of the alkene, the main part of the name is always the portion containing the double bond. And, it is important to identify the carbon atom from which the branch comes. Some examples of the names... 

Other gas-treating processes involving sulfolane are (/) hydrogen selenide removal from gasification of coal, shale, or tar sands (qv) (108) (2) olefin removal from alkanes (109) (J) nitrogen, helium, and argon removal from natural gas (110) (4) atmospheric CO2 removal in nuclear submarines (5) ammonia and H2S removal from waste streams (6) H2S, HCl, N2O, and CO2 removal from various streams (111—120) and (7) H2S and SO2 removal from... 

The principal sources of feedstocks in the United States are the decant oils from petroleum refining operations. These are clarified heavy distillates from the catalytic cracking of gas oils. About 95% of U.S. feedstock use is decant oil. Another source of feedstock is ethylene process tars obtained as the heavy byproducts from the production of ethylene by steam cracking of alkanes, naphthas, and gas oils. There is a wide use of these feedstocks in European production. European and Asian operations also use significant quantities of coal tars, creosote oils, and anthracene oils, the distillates from the high temperature coking of coal. European feedstock sources are 50% decant oils and 50% ethylene tars and creosote oils. 

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