Combustion of ethane

Oxidation of Hydrocarbons. Ethanol is one of a variety of oxygen-containing compounds produced by the oxidation of hydrocarbons. Ethanol is reported to be obtained in a yield of 51% by the slow combustion of ethane (158,159). When propane is oxidi2ed at 350°C under a pressure of 17.2 MPa (170 atm) (160,161), 8% of the oxygen is converted to ethanol. Lower conversions to ethanol are obtained by oxidi2ing butane. Other oxidation systems used to produce ethanol and acetaldehyde (162—164) and methods for separating the products have been described in the patent Hterature. 

Consider the combustion of ethane (C H ) in pure oxygen. If 100 lb of ethane are available and 10% excess oxygen is supplied to ensure complete combustion, calculate (1) the amount of oxygen supplied, and (2) compositions of the reactants and products on mass and molal bases. 

Using the information given in Table 7-II, determine the reaction heat per mole of QHdg) for the complete combustion of ethane. 

In a certain experiment, lOOg of ethane, C2Hh, is burned, (a) Write a balanced chemical equation for the combustion of ethane to produce C02 and water. (b) Determine the number of moles of ethane in 100g of ethane, (c) Determine the number of moles of C02 that would be produced by the combustion of that number of moles of ethane. (d) Determine the mass of C02 that can be produced by the combustion of 100 g of ethane. 

In some cases, the value given in the table depends on that calculated previously for some other bond. For example, to obtain ec-c, we combine the enthalpy of combustion of ethane, —1,588kJ mol , with the proper multiples of the AHm s in Equations (4.38)-(4.41) to obtain the enthalpy change for the reaction... 

Reactions that lead to substantial degradation of molecules into smaller fragments are more difficult to classify. An example is the combustion of ethane to carbon dioxide and water. All of the chemical bonds in the reactants are broken in this reaction. It seems pointless to try to classify this as anything but a complete combustion or oxidation reaction ... 

H2(g) - C2H6(g), from the following data enthalpy of combustion of ethyne, —1300 kf-mol 1 enthalpy of combustion of ethane, —1560 kj-mol-1 enthalpy of combustion of hydrogen, —286 kj-mol-1. 

Equations (1) and (2) are the combustion of hydrogen and ethylene, respectively, and A H° values for these reactions are given in the statement of the problem. Equation (3) is the reverse of the combustion of ethane, and its value of AH° is the negative of the heat of combustion of ethane. (b) Again we need to collect equations of reactions for which the AH° values are known. 

The heat of combustion of ethane gas, CtH. is 1561 kJ/mol. Assuming that 60% of the heat is useful, how many liters of ethane (S.T.P.) must be burned to supply enough heat to convert 50kg of water at 10°C to steam at 100°C ... 

This is unlikely to be other than second order at the pressures used, and it may be difficult to determine whether the reaction to give acetaldehyde (which probably occurs in the combustion of ethane)... 

In the slow combustion of ethane, on the other hand, ethyl alcohol has actually been detected amongst the oxidation products,1 and an analogous scheme is suggested 2 to that for methane. Thus ... 

We know that the ethane-pentane mixture is 5 moles. If we say that the number of moles of C2Hg is x, the number of moles of CgHj2 will be (5-x) moles. Equations for the combustion of ethane and pentane are ... 

It is interesting to note that the It eat ot this reduction can be found without having to carry out the particular reaction at all—it can be obtained, as shown b the calculation we ha e just made, from measurement of the heat of combustion of ethylene, the heat of combustion of ethane, and the heat of combustion of hydrogen. Heats of combustion are ordinarily reliable to about 0 5 percent, which in this case would be 2 kcah llie molal heat ot hydrogenation of ethylene has been determined directly by carrying out the hydrogenation reaction (in the presence of a catalyst) in a calorimeter. The value 32.8 0.1 kcal was obtained by this direct method. 

Write the stoichiometric equations for the combustion of methane with oxygen to form (a) CO2 and H2O and (b) CO and H2O and for the combustion of ethane with oxygen to form (c) CO2 and H2O and (d) CO and H2O, Then prove that only three of these four reactions are independent. 

Write the chemical equations for the complete combustion of ethane, ethene, and ethyne into carbon dioxide and water. (Chapter 10)... 

For a reaction in which some of the coefficients in the balanced equation are not equal to 1, deriving expressions for the changes in the partial pressures of the products and reactants requires care. Consider the combustion of ethane at constant volume ... 

Catalytic Combustion of Ethane over Ehgh Surface Area Lni.xKxMnOs (Ln = La, Nd) Perovskites The effect of Potassium Substitution. 

Monophasic Ln x MnOs (Ln = La, Nd) perovskites with high surface areas (8-27 m /g) were synthesised at mild conditions by the freeze-drying method, and were found to be active for the catalytic combustion of ethane at low temperatures (573 to 648 K). As a general troid, the substitution of the rare earth cation by potassium decreased the intrinsic activity, reduced the reaction order in oxygen and, for the more substituted samples (x>0.10), it increased the selectivity to ethene. It was found that the rare earth cation also influenced the catafytic activity of the substituted perovskites. These effects were analysed in terms of structural modifications induced by the introduction of potassium in the perovskites. 

In the conditions used, all the catalysts were active for the combustion of ethane, producing conversions from 1-5 % at 573 K up to 40 % at 648 K. The only detected products were CO2, H2O and small amounts of ethene, that is consistent with a triangular reaction scheme involving parallel formation of CO2 and ethene and the consecutive combustion of ethene. In separate measurements of CO oxidation on these catalysts, made in a Fl lR cell [26], CO was transformed conipletely into CO2 at tenoperatures as low as 573 K This would e q)lain the absence of CO among the reaction products of ethane oxidation, carried out here at hi er tenq>eratures. Fig. 3 shows the variation of areal rates of ethane oxidation over the LKx and NKx catalysts with terrqrerature. In all cases, ethane conversion increased with increasing... 

The major part of diamond film production is actually covered by the CVD procedures presented in Section 6.3.1. Still there are a few other methods worth mentioning that suit to the generation of diamond films as well. These include, for instance, the flame combustion method. The respective apparatus essentially consists of a modified welding torch burning hydrocarbons at normal pressure (Figure 6.22). The carbon source most commonly applied here is acetylene, but the combustion of ethane, methane, ethylene, or methanol yields diamond films as well. The gas current is mixed with oxygen to support the combustion, but for being rich in hydrocarbon, the mixture does not burn up, and molecules of hydrocarbon still exist in the deposition zone. 

Find AS° for the combustion of ethane (C2H6) to carbon dioxide and gaseous water. Is the sign of AS° as expected ... 

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