Oxygen/nitrogen mixtures

FIQURE 5-1.4b. Effect of pressure on MIE of propane in uarious oxygen-nitrogen mixtures. 

FIGURE 3-10. Flammability diagram for methane-oxygen-nitrogen mixtures. (Courtesy of L. G. Britton.)... 

Bregeon B., Gordon A.S., and Williams F.H., Near-limit downward propagation of hydrogen and methane flames in oxygen-nitrogen mixtures. Combust. Flame, 33 33-45,1978. 

Manufacture Filtered air is compressed and cooled to remove water and carbon dioxide. The oxygen/nitrogen mixture is further cooled in a distillation column and the lower boiling nitrogen distilled from the higher boiling oxygen. 

Thompson, J.D. and Enloe, J.D., Flammability limits of hydrogen-oxygen-nitrogen mixtures, Combust. Flame, 10, 393,1966. 

Let us reconsider the critical flame temperature criterion for extinction. Williams [25], in a review of flame extinction, reports the theoretical adiabatic flame temperatures for different fuels in counter-flow diffusion flame experiments. These temperatures decreased with the strain rate (ua0/x), and ranged from 1700 to 2300 K. However, experimental measured temperatures in the literature tended to be much lower (e.g. Williams [25] reports 1650 K for methane, 1880 K for iso-octane and 1500 K for methylmethracrylate and heptane). He concludes that 1500 50 K can represent an approximate extinction temperature for many carbon-hydrogen-oxygen fuels burning in oxygen-nitrogen mixtures without chemical inhibitors . 

From other more recent studies of NO formation in the combustion of lean and slightly rich methane-oxygen-nitrogen mixtures as well as lean and very rich hydrocarbon-oxygen-nitrogen mixtures, it must be concluded that some of the prompt NO is due to the overshoot of O and OH radicals above their equilibrium values, as the Bowman and Seery results suggested. But even though O radical overshoot is found on the fuel-rich side of stoichiometric, this overshoot cannot explain the prompt NO formation in fuel-rich systems. It would appear that both the Zeldovich and Fenimore mechanisms are feasible. 

Warnatz, J. 1981. Concentration-, pressure-, and temperature-dependence of the flame velocity in hydrogen-oxygen-nitrogen mixtures. Combustion Science Technology 26 203-14. 

In another paper Freiwald Koch described (Ref 24) investigation of spherical detonations of acetylene-oxygen-nitrogen mixtures as a function of nature and strength of initiation... 

E.Jones, JSCI 69,206-12<1950)(Umits for the propagation of flame in acetaldehyde-oxygen-nitrogen mixtures) e)J. d Ans et al, AngChem 66,633-5(1954) CA 49,10832 (1955) (Peroxide derivatives of acetaldehyde, prepd by treating AcH with peroxy acids. All the compds are highly explosive)(16 references)... 

Investigation of the Ignition Delay Times for Propylene Oxide-Oxygen-Nitrogen Mixtures ,... 

For example, gas mixtures were prepared containing 3.8 mg. per liter of 2,2-DMB in oxygen-nitrogen mixtures ranging from 10 to 60% 02. The percentage of the hydrocarbon which was oxidized was determined over a catalyst surface temperature range of 400° to 900°C. (Figure 3). 

Acetaldehyde Oxidation. In the oxidation of acetaldehyde with oxygen-nitrogen mixtures, at conditions under which the rate-limiting factor is oxygen transfer to the solution, manganese (II) acetate gives a better efficiency to acetic acid than copper (II) acetate, which in turn is better than cobalt (II) acetate. However, when either cobalt (II) or copper (II) acetate is used in the presence of manganese (II) acetate, the... 

Figure 6. Burning velocity as function of equivalence ratio and oxygen concentration for propane-oxygen-nitrogen mixtures at 311° K., measured by schlieren total-area burner method (79)...

There were experiments [158] studying formation of nitric oxides in nitrogen plasma jet with injected oxygen, oxygen-nitrogen mixture and water. In this case, NO concentration in nitrous gases reached 8%. 

Heylmun, G. W. Improved analysis of argon-oxygen-nitrogen mixtures by gas chromatography. J. Gas Chromatog. 3, 82 (1965). 

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