Homogeneous energy supply

A search for alternative energy supplies has triggered efforts to develop efficient homogeneous catalysts for Fischer-Tropsch-type syntheses via hydrogenation of carbon monoxide, a likely future key material available, for example, through oxidation of coal (33, 327, 328, 417, 418). Metal cluster systems have been used in attempts to emulate the presently used heterogeneous catalysts. The important reactions are methanation,... 

The production of an homogeneous atomic vapour from a sample is achieved by aspirating a solution into a flame or evaporating small volumes in an electrically heated tube furnace or from the surface of a carbon rod. In all cases, the thermal energy supplied must (a) evaporate the solvent and (b) dissociate the remaining solids into their constituent atoms without causing appreciable ionization. 

In the homogeneous phase under thermodynamically favorable temperature conditions, the formation of ammonia may be forced by employing other forms of energy, such as electrical energy or ionizing radiation. The principal difficulty with these so-called plasma processes, which also impedes their economic use, is that the energy supplied is useful only in part for ammonia formation. A greater part is transformed in primary collision and exothermic secondary processes into undesirable heat or unusable incidental radiation. 

Schnerr, G., "2D transonic flow with energy supply by homogeneous condensation ", Experiments in Fluids,Vol.7,1989, pp. 145-156. 

Schnerr, G.H., Dohrmann, U. Transonic Flow Around Airfoils with Relaxation and Energy Supply by Homogeneous Condensation. AIAA paper 89-1834, Fluid Dynamics and Lasers Conf., Buffalo, N. Y. (1989)... 

As we have seen, there is abundant evidence that the heat of activation in homogeneous reactions represents the thermal energy with which the molecules must be supplied, by collision or otherwise, before they can enter into reaction. There is every reason to believe that, in heterogeneous reactions, adsorbed molecules must be supplied with energy in an analogous way. 

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