Butanes reaction

The theoretical explanation of the butane reaction mechanism is as fully developed as is that of acetaldehyde oxidation (51). The theory of the naphtha oxidation reaction is more troublesome, however, and less well understood. This is largely because of a back-biting reaction which leads to cycHc products (52). 

Chlorouranate salts, heat of formation, 34 97 Chloroxyperfluoro-fert-butane, reactions, 26 140-145... 

The relative importance of the two pathways is reflected in the ratio of the yields of the hydroxycar-bonyls compared to the carbonyl products with the same number of carbons as the parent compound as well as in the absolute yields of the latter products. Thus the carbonyl product yields decrease from 70% for the n-butane reaction to 0.7% for the n-octane reaction at the same time, the ratio of hydroxycarbonyl products to carbonyls increases from 0.14 to 50 (Kwok... 

As to the method of preparation, it was found that V-Mg oxide catalysts prepared with a Mg(OH)2 precursor that was precipitated with KOH was less selective than one prepared with a MgC03 purecursor precipitated with (NH4)2C03 (25). Interestingly, unlike the butane reaction, there was no effect of preparation on the oxidative dehydrogenation of propane using the same catalysts, as mentioned earlier (25, 30). Unlike the oxidation of propane, Mg pyrovanadate was nonselective for butane (25, 26). Mg metavanadate was nonselective as well (26). 

Fig. 7. Differential heat of reoxidation and selectivity for oxidative dehydrogenation of butane on V2Ov y -AFO, samples. For the 2.9 V/nm2 sample, the selectivity was calculated for the detected gaseous products, (a) 8.2 V/nm2 sample, reaction at 400°C (b) 2.9 V/ntn2 sample, reaction at 480°C (c) 8.2 V/nm2 sample, reduction by CO at 530°C, butane reaction at 400°C and (d) 2.9 V/nm2 sample, reduction by CO at 400°C, butane reaction at 480°C. (a) and (b) are from Ref. 50 (c) and (d) and from P. J., Andersen, Ph D. thesis, Northwestern University, 1992.

Stibolanes (5) are known as the 1-phenyl and 1-methyl derivatives, which are prepared by similar methods and form similar derivatives to the arsolanes. In addition, 1-methyl-stibolane (11) has recently been prepared by the disproportionation of a,w-bis(dimethyl-stibino)butane (reactions 4, 5). 

It will now be instructive to examine the n-butane reaction (76). In this case the reaction follows almost exclusively a single path leading to the formation of sec-butyl radicals. The percentage of the quenching done by the two methylene groups is very nearly the same as that for the tertiary C-H bond in isobutane (i.e. >90%). However, the primary yield of w-butyl radicals ( 2%) from w-butane is decidedly less than that for isobutyl radicals ( " 14%) from isobutane. This behavior can be readily interpreted on the basis of a cyclic transition-state structure, but not with an open-chain transition state. For the two reaction sequences, we may write ... 

These systems are common in liquid extraction and also in a multiphase reactor with an organic and an aqueous phase. Common sources of pollution are incomplete separation and contamination due to trace organics in the aqueous phase. An example is in alkylation reactions (e.g., n-butane reaction with olefins to form isooctanes). Strong acids, such as sulfuric and hydrofluoric acids, are used as catalysts, and the recovery and the recycle of acid need to be optimized in order to reduce the waste generation. 

Product distribution from ketene and diazomethane 778 photolysis in the presence of 2,3-dimethyl-2,3-epoxy-butane. Reaction with CH2(d A,)... 

Some fraction of the RO. radical pool, usually 10% or less, produce alkyl nitrate, RONO., upon reaction with NO by 5.59b. This termination step removes both a radical and a molecule of NO,. About 8% of the RO. radicals formed from the OH-/i-butane reaction will lead to nitrate when reacting with NO. As noted in Section 5.8.1, this percentage increases with the size of the hydrocarbon molecule, reaching about 33% for n-octane. The organic components of RONO. can react with OH to continue the VOC photooxidation cycle, although the possibility of re-releasing NO, as a result of these reactions is uncertain at present. 

IrsMo) prepared from the bimetallic carbonyl complex was somewhat more active for the -butane reaction at 488 K than a pure iridium catalyst, but high ethane selectivity was retained (1.43). The IraMoa complex gave a less active catalyst, with a lower value of S2 (1.08). The addition of zirconium to platinum (Pt7sZr25/C) lowered the rate of ethane hydrogenolysis about 20-fold, and raised the activation energy. ... 

The currently practiced process is a two-step process, comprising -butane isomerization and successive isobutane dehydrogenation. The n-butane dehydroisomerization (Reaction 5.3) involves the dehydrogenation of n-butane (Reaction 5.1) and successive isomerization to isobutene (Reaction 5.2). The main products measured were normal butene, isobutane, and isobutene ... 

Figure IV-B-5. Arrhenius plot for the rate coefficients for the NO3 + butanal reaction.

Cl + butanal reaction has been studied using pulsed laser photolysis, coupled with resonance fluorescence, over the temperature range 265-380 K by Cuevas et al. (2006), and by relative rate methods at room temperature by Ullerstam et al. (2001), Wu and Mu (2007), and Singh et al. (2009) see table IV-B-12. There is a discrepancy of 30% between the room temperature measurements the unweighted mean is 1.66 X 10 cm molecule" s , with an uncertainty of 25%. Using the temperature dependence of Cuevas et al. and this mean value gives = 3.8 x 10 exp(446/r) cm molecule ... 

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