High-temperature production

A. T. Santhanam, G. P. Grab, G. A. Rolka, and P. Tierney, Proceedings of the Conference on High Temperature Productivity Machining—Materials and Processes, New Orleans, La., American Society for Metals, 1985, pp. 113—121. 

When rhodium is combined with platinum and palladium, the elements together form the internal metals of automobile catalytic converters, which convert hot unburned hydrocarbon exhaust gases to less harmful CO and H O. Similar alloys are used to manufacture high-temperature products such as electric coils for metal refining furnaces and high-temperature spark plugs. 

When high-temperature products are in an equilibrium state, many of the constituent molecules dissociate thermally. For example, the rotational and vibrational modes of carbon dioxide are excited and their mohons become very intense. As the temperature is increased, the chemical bonds between the carbon and oxygen atoms are broken. This kind of bond breakage is called thermal dissociation. The dissociahon of H2O becomes evident at about 2000 K and produces H2, OH, O2, H, and O at 0.1 MPa. About 50% of H2O is dissociated at 3200 K, rising to 90% at 3700 K. The products H2, O2, and OH dissociate to H and O as the temperature is increased further. The fraction of thermally dissociated molecules is suppressed as the pressure is increased at constant temperature. 

European Commission (2007), Innovative High Temperature Production Routes for H2 Production - Co-ordinated Action (INNOHYP CA), Final Report, Contract no. 513550, April. 

The low-pressure or high-temperature production of formaldehyde is almost certainly due to reaction (18), whereas the equal amounts of formaldehyde and methanol under other conditions can more readily be attributed to a reaction which gives both simultaneously, e.g.,... 

Renner, E. 1988. Storage stability and some nutritional aspects of milk powders and ultra high temperature product at high ambient temperatures. J. Dairy Res. 55, 125-142. 

In rockets burning liquid fuels the oxidizing agent (e.g., liquid oxygen) is pumped from tanks into the combustion chamber. Simultaneously, fuel (e.g., kerosene) is pumped into the chamber and burned. The combustion takes place at a constant high pressure and produces high-temperature product gases tha are expanded in a nozzle, as indicated in Fig. 8.14. 

High-temperature products around cool stars... 

Figure 8.6 Illustration of the typical peak temperatures and cooling rates for high-temperature products. For details on the individual group of objects, see the corresponding sections in the text.

Resin Mode of thermal decomposition Low-temperature products High-temperature products... 

Colin G. Fink. Ph. D. Consulting Electrometallurgist. Secretary, Amer. Electro-chem. Soc. High Temperature Production. 

Also notable is that half of the potential energy of the incoming fuel is destroyed immediately by the boiler (30% is used up in combustion, 15% is consumed in the heat transfer from high-temperature products to the steam and preheated air, and 5% is... 

---