Atmospheric mixing thermodynamics

Ma.nufa.cture. Nickel carbonyl can be prepared by the direct combination of carbon monoxide and metallic nickel (77). The presence of sulfur, the surface area, and the surface activity of the nickel affect the formation of nickel carbonyl (78). The thermodynamics of formation and reaction are documented (79). Two commercial processes are used for large-scale production (80). An atmospheric method, whereby carbon monoxide is passed over nickel sulfide and freshly reduced nickel metal, is used in the United Kingdom to produce pure nickel carbonyl (81). The second method, used in Canada, involves high pressure CO in the formation of iron and nickel carbonyls the two are separated by distillation (81). Very high pressure CO is required for the formation of cobalt carbonyl and a method has been described where the mixed carbonyls are scmbbed with ammonia or an amine and the cobalt is extracted as the ammine carbonyl (82). A discontinued commercial process in the United States involved the reaction of carbon monoxide with nickel sulfate solution. 

The interfacial tension of mixed adsorbed films of 1-octadecanol and dodecylammonium chloride has been measured as a function of temperature at various bulk concentrations under atmospheric pressure. The transition interfacial pressure of 1-octadecanol film has been observed to increase with the addition of dodecylammonium chloride and then to disappear. The interfacial pressure vs mean area per adsorbed molecule curves have been illustrated at a constant mole fraction of adsorbed molecules. With the aid of the thermodynamic treatment developed previously, we find that the mutual interaction between 1-octadecanol and dodecylammonium chloride molecules in the expanded state is similar in magnitude to the interaction between the scime kind of film-forming molecules. 

In these studies, thermodynamic equilibrium conditions were assumed. Constant pH monitoring was used as an estimator of the equilibration times involved, since a stable pH is an overall indicator of the Internal chemical stability of pH dependent processes. In order to allow the assumptions of atmospheric O2 and CO2 partial pressures, water scrubbed compressed air was pumped into the reaction vessels under constant temperature and constant vigorous mixing conditions. The air was introduced by fritted glass bubblers which had been teflon coated while air flowed through them in order to minimize the glass-solution interface. 

Tang I. N. (1997) Thermodynamic and optical properties of mixed-salt aerosols of atmospheric interest. J. Geophys. Res. 102, 1883-1893. 

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