Reactions Among Solids Through Fluid Intermediates

Reactions Among Solids Through Fluid Intermediates 

Many reactions among solids are important with regard to pyrometallurgical processes. While some of these reactions are true solid-solid reactions, some others occur through fluid intermediates. For instance, the carbothermic reduction of many metal oxides proceeds through the gaseous intermediates CO and C02 in the following manner  

In these reactions there is a net generation of the gases CO and C02 this leads to a bulk flow of the gas mixture from the reaction zone. There are other types of reactions involving gaseous intermediates, in which there is no net gas generation. An example is the formation of a metal carbide from the metal and carbon  

Reactions among solids occurring through gaseous intermediates can be viewed as coupled gas-solid reactions, and thus can be analyzed in the light of the discussions presented in the preceding sections regarding fluid-solid reactions. 

Apart from pyrometallurgy, the various ingredients of heterogeneous reaction kinetics are also very pertinent to several hydrometallurgical operations. This will be discussed in Chapter 5. 

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Reactions Among Solids Through Fluid Intermediates... 

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