Ethane production

The dephlegmator process recovers a substantially higher purity C2+ hydrocarbon product with 50—75% lower methane content than the conventional partial condensation process. The C2+ product from the cryogenic separation process can be compressed and further separated in a de-ethanizer column to provide a high purity C3+ (LPG) product and a mixed ethylene—ethane product with 10—15% methane. Additional refrigeration for the deethanization process can be provided by a package Freon, propane or propylene refrigeration system. 

It seems prudent not to speculate on the source of ethane products containing three D atoms more than the reactant form, except, perhaps to suggest that direct radiolysis or energy transfer may produce precursors of these as well as minor portions of the other products. 

Studies in deuterated water have shown that the hydroxyl proton does not end up in the ethanal formed. The decomposition of the 2-hydroxyethyl is not a simple P-elimination to palladium hydride and vinyl alcohol, which then isomerises to ethanal. Instead, the four protons stemming from ethene are all present in the initial ethanal product [6] (measured at 5 °C in order to suppress deuterium/hydrogen exchange in the product) and most authors have therefore accepted an intramolecular hydride shift as the key-step of the mechanism (see Figure 15.2). There remains some doubt as to how the hydride shift takes place. 

Fig. ii. Selectivity for ethane production from n-butane hydrogenolysis on iridium as a function of effective particle size. (From R s. HI. 112.) Also shown are data for n-butane hydrogenolysis on supported Ir catalysts The temperature is 47S K in all cases. 

Ramstock ER et al Trialkyl lead metabolism and lipid peroxidation in vivo in vitamin E-and selenium deficient rats as measured by ethane production. Toxicol Appl Pharmacol 54 251-257, 1980... 

For the photolysis of ferf-butyl nitrite a possible reaction mechanism (Scheme 6) consists of the production of ferf-butoxy radicals (equation 3), followed by their decomposition to give acetone and methyl radicals (equation 4). The latter are trapped by the nitric oxide liberated in the first step (equation 5). However, the absence of ethane production in the actual experiments suggested that an intramolecular formation of nitrosomethane is unlikely ". ... 

Dry gas consists of hydrogen, methane, and ethane products. The best linear regression model to predict dry gas yield for catalyst A has the form ... 

Ivanov, V, Rahier, J. Lauwerys, R. (1989) Lipid peroxidation in acrylonitrile-treated rats, evidenced by elevated ethane production. J. appl. Toxicol., 9, 353-358... 

In contrast with these observations, it has been found that manganese and iron oxide supported on magnesium oxide catalyze cracking reactions via a free-radical mechanism and ensure enhanced ethylene and ethane production.64... 

Phillips, Qatar Petroleum, and Total is investing in a 1.3 mmt/year cracker in Ras Laffan, Qatar. However, because ethane production is linked to gas and oil production, the Middle East ethane supply will be able to meet only around 17 percent of global ethylene demand, which is expected to be 135 mmt/year by 2010 (Fig. 7.6). 

Mo oxidation state. These Mo catalytic systems show similar ethylene-ethane product ratios in the reduction of acetylene (see Table VI). The ESR result appears to correspond well to the recent electrochemical result (20, 21). 

An impartial decision has not yet been given as to whether the ethane production depends upon a direct union of the anions or upon the oxidation of an intermediate product, like acetic acid, acetic anhydride, or acetyl superoxide. 

The ligands to be eliminated must be cis to one another for reductive elimination to occur. This is because the process is concerted. Two examples from palladium chemistry make this point clear. Warming in DMSO causes ethane production from the first palladium complex because the two methyl groups are cis in the square planar complex. The more elaborate second bisphosphine forces the two methyl groups to be trans and reductive elimination does not occur under the same conditions. Reductive elimination is one of the most important methods for the removal of a transition... 

Products sales gas contains negligible propane and butane value = 2.85/GJ (LHV). Ethane product contains 1.0 mol% methane, 2.0 mol% propane, negligible butane value = 0.18/kg. 

Over all of the products, the production cost is 7.19/GJ. This produces ethane at 373/t. However, if the natural gasoline is sold according to the prevailing crude oil price (assumed to be 70/bbl) then this will generate by-product credit of 556 million this is based on valuing the gasoline as naphtha with oil at 70/barrel. The basis of this oil price as a reference (index) price is discussed in the Appendix. This approach reduces the production costs and hence the unit ethane and LPG costs. The ethane production cost is 341/t. 

The steam pyrolysis of LPG follows the same pathway of that for ethane, namely by a complex branching chain free radical mechanism. This can be divided into initiation, chain propagation and chain termination reactions. This gives rise to a large number of intermediates and products. As with ethane, products of higher carbon number than the feed are formed. 

Methane and ethane production in the ethylene oxide flame suggest the participation of methyl radicals... 

TET. The products from the pyrolysis of TET were always more varied than from TMT and comprised nitrogen, methane, ethane, diethylamine (DEA), diethylmethylamine (DEMA), ethylethylideneamine (EEA), tetraethylhydrazine (TEH), and two other products, one of which is possibly ethylamine. The dimerization-disproportionation ratio for the diethylamine radicals is approximately 1 to 1 at 250° C. and the other products are produced only in the upper region of temperatures employed by us. Thus at 240° the major products were the dimerization and disproportionation products (TEH, DEA, EEA), and the occurrence of DEMA at the higher temperatures was always accompanied by methane and ethane production. 

Burk RF and Lane JM (1979) Ethane production and liver necrosis in rats after administration of drugs and other chemicals. Toxicology and Applied Pharmacology 50 467. 

Fig. 11. Relative rates of methane and ethane production upon removal, at l = 0, of CO from the + CO feed. Two experiments are being depicted, with steady state ratios of Hj/CO of 6.0 ( ) and 3.1 (A). (Arrows indicate the time at which the CO band absorbance goes to zero.) From (37).

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