Ethane flames

V. Hennessey, R. J., Robinson, C., and Smith, D. B. (1988). A comparative study of methane and ethane flames. TWenty First Symposium International) on Combustion, p. 761. The Combustion Institute, Pittsburgh. 

McKinney MA, Dietz R, Sonne C, De Guise S, Sklmisson K, Karlsson K, Stemgrimsson E, Letcher RJ (2011) Comparative hepatic microsomal biotransformation of selected PBDEs, including decabromodiphenyl ether, and decabromodiphenyl ethane flame retardants in Arctic marine-feeding mammals. Environ Toxicol Chem 30 1506-1514... 

N.M. Marinov, W.J. Pitz, C.K. Westbrook,M.J. Castaldi, and S.M. Senkan. Modeling of Aromatic and Polycyclic Aromatic Hydrocarbon Formation in Premixed Methane and Ethane Flames. Combust. Sci. Techn., 116 211-287,1996. 

Firemaster 6S0. [Velsicol] Bis (tri-bromophenoxy) ethane flame retardant forABS. 

Bis (tribromophenoxy) ethane flame retardant, lubricants Perchloropentacyclodecane Triaryl phosphate... 

Specimen ABS with 16% Bis(tribromo phenoxy) ethane flame retardant... 

The hydrocarbons are separated in another column and analyzed by a flame ionization detector, FID. As an example, Figure 3.13 shows the separation obtained for a propane analyzed according to the ISO 7941 standard. Note that certain separations are incomplete as in the case of ethane-ethylene. A better separation could be obtained using an alumina capillary column, for instance. 

There is no satisfactory chemical way of distinguishing betn een ethane and methane, both of which burn with an almost non-luminous flame this fact however is quite unimportant at this stage of the investigation. Hydrogen also burns with a non-luminous flame and w hen the open end of a test-tube full of the gas is placed in a Bunsen flame, a mild explosion with a very characteristic report takes place. 

Ethane. Ethane VPO occurs at lower temperatures than methane oxidation but requires higher temperatures than the higher hydrocarbons (121). This is a transition case with mixed characteristics. Low temperature VPO, cool flames, oscillations, and a NTC region do occur. At low temperatures and pressures, the main products are formaldehyde, acetaldehyde (HCHOiCH CHO ca 5) (121—123), and carbon monoxide. These products arise mainly through ethylperoxy and ethoxy radicals (see eqs. 2 and 12—16 and Fig. 1). 

H. Bockborn and co-workers, "Production of Acetylene ia Premixed Flames and of Acetylene—Ethylene Mixtures," Chem. Ing. Pechnol. 44(14), 869 (1972). "Thermal Decomposition of Ethane ia a Plasma Jet," Rogyo Kagaku Zasshil4(9), 83 (1971). 

When acetylene is recovered, absorption—desorption towers are used. In the first tower, acetylene is absorbed in acetone, dimethylformarnide, or methylpyroUidinone (66,67). In the second tower, absorbed ethylene and ethane are rejected. In the third tower, acetylene is desorbed. Since acetylene decomposition can result at certain conditions of temperature, pressure, and composition, for safety reasons, the design of this unit is critical. The handling of pure acetylene streams requires specific design considerations such as the use of flame arrestors. 

Transient computations of methane, ethane, and propane gas-jet diffusion flames in Ig and Oy have been performed using the numerical code developed by Katta [30,46], with a detailed reaction mechanism [47,48] (33 species and 112 elementary steps) for these fuels and a simple radiation heat-loss model [49], for the high fuel-flow condition. The results for methane and ethane can be obtained from earlier studies [44,45]. For propane. Figure 8.1.5 shows the calculated flame structure in Ig and Og. The variables on the right half include, velocity vectors (v), isotherms (T), total heat-release rate ( j), and the local equivalence ratio (( locai) while on the left half the total molar flux vectors of atomic hydrogen (M ), oxygen mole fraction oxygen consumption rate... 

Examples for necessary process improvements through catalyst research are the development of one-step processes for a number of bulk products like acetaldehyde and acetic acid (from ethane), phenol (from benzene), acrolein (from propane), or allyl alcohol (from acrolein). For example, allyl alcohol, a chemical which is used in the production of plasticizers, flame resistors and fungicides, can be manufactured via gas-phase acetoxylation of propene in the Hoechst [1] or Bayer process [2], isomerization of propene oxide (BASF-Wyandotte), or by technologies involving the alkaline hydrolysis of allyl chloride (Dow and Shell) thereby producing stoichiometric amounts of unavoidable by-products. However, if there is a catalyst... 

Two GC columns Porapak Q (for C02 and water analyses) and Molecular sieve 5A (hydrogen, oxygen, and CO) were used with two thermal conductivity detectors and another GC column with modified y-Al203 (methane, ethane, ethene, propane, propene, and C4 hydrocarbons) was used with a flame ionisation detector. Carbon and oxygen balances were within 100+5%. 

The gaseous atmosphere was then vented through a trap at -78° (to remove most of the benzene vapor) into an evacuated vessel. Samples were removed by gas-tight syringe and injected into a Hewlett-Packard 5790 gas chromatograph, equipped with a U ft, 1/8 in Porapak P column and a flame ionization detector. Use of known samples of hydrocarbons (methane and ethane) established that the minimum detectable amounts of product by this procedure were about 0.5-1 0 % (based on starting Nb complex). Several of the reactions (Mo(CO)g, W(C0)g and Ru (CO) p) gave small amounts (around 1-2 %) of these alkanes only with Cr(C0)g was a substantial yield of hydrocarbon product consistently observed (see below). 

Calculate the adiabatic flame temperature (at constant pressure) for ethane C2H6 in air ... 

Chlorinated additive flame retardants, 11 468-470, 471-473t Chlorinated aromatics, 6 242 decomposition using microwaves, 16 555 Chlorinated butyl rubber, 4 436 development of, 4 434 manufacture, 4 400, 442-444 Chlorinated ethanes... 

D. A. Pittam, G. Pilcher. Measurements of Heats of Combustion by Flame Calorimetry. Part 8. Methane, Ethane, Propane, n-Butane and 2-Methylpropane. J. Chem. Soc. Faraday Trans. 11972, 68, 2224-2229. 

They exhibit cool flames, except in the cases of methane and ethane. 

Of course, all the appropriate higher-temperature reaction paths for H2 and CO discussed in the previous sections must be included. Again, note that when X is an H atom or OH radical, molecular hydrogen (H2) or water forms from reaction (3.84). As previously stated, the system is not complete because sufficient ethane forms so that its oxidation path must be a consideration. For example, in atmospheric-pressure methane-air flames, Wamatz [24, 25] has estimated that for lean stoichiometric systems about 30% of methyl radicals recombine to form ethane, and for fuel-rich systems the percentage can rise as high as 80%. Essentially, then, there are two parallel oxidation paths in the methane system one via the oxidation of methyl radicals and the other via the oxidation of ethane. Again, it is worthy of note that reaction (3.84) with hydroxyl is faster than reaction (3.44), so that early in the methane system CO accumulates later, when the CO concentration rises, it effectively competes with methane for hydroxyl radicals and the fuel consumption rate is slowed. 

FIGURE 8.21 Comparison of the radial profiles for scattering cross-section gvv and temperature (uncorrected) as a function of radial position for a coannular ethane diffusion flame (from Santoro et al. [85]). 

Nomeir AA, Markham PM, Ghanayem BI, Chadwick M (1993) Disposition of the flame retardant 1,2- bis(2,4,6-tribromophenoxy)ethane in rats following administration in the diet. Drug Metab Dispos 21 209-214... 

Nakari T, Huhtala S (2010) In vivo and in vitro toxicity of decabromodiphenyl ethane, a flame retardant. Environ Toxicol 25 333-338... 

CA 53, 17513 (1959). Materials useful as rocket fuels, semisolid or gelled fuels for bursting and tail-ejection-type bombs, and incendiary fuels for flame throwers and hand grenades are described. They are made by mixing 0.1-25% by wt of satd, unsatd, or aromatic nitrohydrocarbons or their mixts, such as nitro- or dinitromethane, -ethane, -propane, or -butane with divinylated ketoses or diaryl deoxyketitols prepd by reaction of C3 g ketose sugars with C6 M aromatic hydrocarbons. The latter include CfiH, toluene, naphthalene, anthracene and their alkylated derivs... 

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