Ethyl nitrate, decomposition

A number of other gases can undergo reactions that produce decomposition flames—for instance, ethylene, ethylene oxide, methyl nitrate, ethyl nitrate, and hydrazine (CCPS 1993). 

Ethylhexyl nitrate, 2 23 2-Ethylhexylpotassium, 14 256 2-Ethylhexyl salicylate, 22 16 2-Ethylhexylsodium, 14 255 Ethyl hydroperoxides, decomposition hazards of, 18 490 Ethylhydroxyethylcellulose (EHEC),... 

Acetone cyanohydrin nitrate will not nitrate amines with branching on the carbon a to the nitrate group. For these substrates the use of ethyl nitrate and lithium bases is favoured. a-Aminonitriles are frequently observed as impurities under the reaction conditions because of the slow decomposition of acetone cyanohydrin nitrate to hydrogen cyanide and acetone. The need for an excess of amine during these reactions is wasteful and only practical if this component is cheap and widely available. Other cyanohydrin nitrates are less efficient N-nitrating agents. ... 

The primary step in the decomposition of ethyl nitrate (C2H5ONO2) is again the breaking of the C2H5O-NO2 bond, and the decomposition rate obeys a first-order law. The decomposition process of ethylene glycol dinitrate can be written as [29]... 

Ellis and coworkers studied the effect of lead oxide on the thermal decomposition of ethyl nitrate vapor.P l They proposed that the surface provided by the presence of a small amount of PbO particles could retard the burning rate due to the quenching of radicals. However, the presence of a copper surface accelerates the thermal decomposition of ethyl nitrate, and the rate of the decomposition process is controlled by a reaction step involving the NO2 molecule. Hoare and coworkers studied the inhibitory effect of lead oxide on hydrocarbon oxidation in a vessel coated with a thin fQm of PbO.P l They suggested that the process of aldehyde oxidation by the PbO played an important role. A similar result was found in that lead oxide acts as a powerful inhibitor in suppressing cool flames and low-temperature ignitions.P l... 

Ellis, W. R., Smythe, B. M., and The-harne, E. D., The Effect of Lead Oxide and Copper Surfaces on the Thermal Decomposition of Ethyl Nitrate Vapor,... 

D) J.B. Levy, "The Effect of Additives on the Thermal Decomposition of Ethyl Nitrate ,... 

The use of ethyl nitrate as a component of rocket fuel involves the problem of thermal decomposition. Levy [16] has studied the decomposition of ethyl nitrate in the gaseous phase, in the temperature range 161 and 201°C under a pressure of a few centimeters of mercury. He found that ethyl nitrite is the main decomposition product. By-products include methyl nitrite, nitromethane, nitrogen dioxide and nitrous oxide. 

Using their own data on the decomposition of ethyl nitrate between 180 and 215°C under pressures of 30-50 mm Hg, Adams and Bawn [17] have calculated the activation energy E and the constant B ... 

Trimethylene glycol occurs in the glycerin which is produced by fermentation. There is no harm in leaving it in glycerin which is to be used for the manufacture of explosives. It may however be separated by fractional distillation. When pure it is a colorless, odorless, syrupy liquid, specific gravity (x°/4°) 1.0526 at 18°. It mixes with water in all proportions and boils at atmospheric pressure at 21 i° without decomposition. At temperatures above 15° or so, it is oxidized rapidly by nitric acid or by mixed acid. It is accordingly nitrated at 0-10° under conditions similar to those which are used in the preparation of ethyl nitrate and other simple aliphatic nitric esters (except methyl nitrate). 

Most of the ethyl nitrate decomposes in the high temperature region (740—800 °K) of the flame where it is believed that unimolecular thermal decomposition [129] is the rate controlling process. The rate equation given above corresponds to a unimolecular reaction in its low-pressure region and the pre-exponential term suggests that the activation energy is distributed over about 10 square terms. 

The mechanisms of n- and iso-propyl nitrate decomposition flames appear to be the same as that of the ethyl nitrate flame, the main attack on the nitrate ester being by nitrogen dioxide and nitrous acid [136]. 

The thermal decomposition of alkyl nitrates has received continuous attention over a number of years. The introduction of improved techniques has required the periodic re-evaluation of data on these very complex reactions . The substrate of choice has been ethyl nitrate. Early studies on the thermal decomposition suggested that the reaction became complex after the initial fission into ethoxy radicals and nitrogen dioxide . 

It has been observed that the activation energy for thermal decomposition of ethyl nitrate is substantially reduced in the presence of lead oxide or copper surfaces. Above 200° C approximately, the thermolysis of ethyl nitrate becomes much more complex and detonation in the gas phase is common. In the range 242-260° C the reaction was found to be half-order, with an overall rate coefficient" k = 10 - exp(—46,800)/J 7 mmole. l . sec apparently the initiation step is unaltered but the subsequent radical chain mechanism affects the overall rate of decomposition. 

Ethyl nitrate is currently an important component of liquid rocket fuel. In that respect considerable work is being done to elucidate the mechanism ol thermal decomposition by Pollard, U. S, Marshall and Pedlcr [1511 - Some frag ments of their mechanism are as follows (16) ... 

In the second series of experiments, the products from the photo-oxidation of diethyl ether, carried out in a Teflon bag reactor at ppm and ppb levels, have been determined by withdrawing vapour samples and monitoring by gas chromatography, HPLC and by chemiluminescence analysis. The major reaction products which have been measured are ethyl formate, ethyl acetate, acetaldehyde, formaldehyde, PAN, methyl nitrate and ethyl nitrate. The products observed arise from the decomposition reactions of the 1-ethoxyethoxy radical and from its reaction with oxygen. The data enable the establishment of a quantitative mechanism for the photo-oxidative reaction. In addition the rate of conversion of NO to NO2, determined by chemiluminescence analysis, shows that for each molecule of ether reacted only one molecule of NO is converted to NO2. In further end-product analyses experiments, the OH radical initiated photo-oxidation of n-hexane or the photolyses of 2- or 3-hexyl nitrites were studied to examine the... 

The major products were ethyl formate and formaldehyde and the minor products were ethyl acetate, acetaldehyde, peroxyacetyl nitrate, and methyl and ethyl nitrates. The products arise from the decomposition reactions of the 1-ethoxyethoxy radical and from its reaction with molecular oxygen ... 

The additives for improving the cetane number, called pro-cetane, are particularly unstable oxidants, the decomposition of which generates free radicals and favors auto-ignition. Two families of organic compounds have been tested the peroxides and the nitrates. The latter are practically the only ones being used, because of a better compromise between cost-effectiveness and ease of utilization. The most common are the alkyl nitrates, more specifically the 2-ethyl-hexyl nitrate. Figure 5.12 gives an example of the... 

Attempts to prepare the anhydrous nitrate by dehydration always fail because of decomposition to a basic nitrate or to the oxide, and it was previously thought that Cu(N03)2 could not exist. In fact it can be obtained by dissolving copper metal in a solution of N2O4 in ethyl acetate to produce Cu(N03)2.N204, and then driving off the N2O4 by heating this at 85-100°C. The observation by C. C. Addison... 

The kinetics of the various reactions have been explored in detail using large-volume chambers that can be used to simulate reactions in the troposphere. They have frequently used hydroxyl radicals formed by photolysis of methyl (or ethyl) nitrite, with the addition of NO to inhibit photolysis of NO2. This would result in the formation of 0( P) atoms, and subsequent reaction with Oj would produce ozone, and hence NO3 radicals from NOj. Nitrate radicals are produced by the thermal decomposition of NjOj, and in experiments with O3, a scavenger for hydroxyl radicals is added. Details of the different experimental procedures for the measurement of absolute and relative rates have been summarized, and attention drawn to the often considerable spread of values for experiments carried out at room temperature (-298 K) (Atkinson 1986). It should be emphasized that in the real troposphere, both the rates—and possibly the products—of transformation will be determined by seasonal differences both in temperature and the intensity of solar radiation. These are determined both by latitude and altitude. 

Ethyl 3,4-dihydroxybenzenesulfonate, Oleum Dohmen, E. A. M. F. et al., Chem. Weekbl., 1942, 39, 447-448 Attempted nitration of the sulfonate in 20% oleum led to a violent explosion, probably from decomposition of the nitrate. 

In the past, dissociation of the nucleoprotein complex has been brought about by salt solutions or by heat denaturation,129 but, more recently, decomposition has been effected by hydrolysis with trypsin,126 or by the use of dodecyl sodium sulfate130 or strontium nitrate.131 Some virus nucleoproteins are decomposed by ethyl alcohol.132 This effect may be similar to that of alcohol on the ribonucleoproteins of mammalian tissues. If minced liver is denatured with alcohol, and the dried tissue powder is extracted with 10% sodium chloride, the ribonucleoproteins are decomposed to give a soluble sodium ribonucleate while the deoxyribonucleoproteins are unaffected.133 On the other hand, extraction with 10 % sodium chloride is not satisfactory unless the proteins have first been denatured with alcohol. Denaturation also serves to inactivate enzymes of the tissues which might otherwise bring about degradation of the nucleic acid during extraction. 

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