MODELS FOR REACTIVE SOLID PARTICLES

we will mainly consider reactions between a gas-phase component A and a solid-phase component B. The stoichiometry of the reaction is 

FIGURE 8.2 (a) A reactive particle with a product layer, (b) Reactant and product concentrations for the reaction A(g) -I-B(s) R(g) + S(s) in a solid particle with a product layer. (Data from Levenspiel, O., Chemical Reaction Engineering, 3rd Edition,Wiley, New York, 1999.) 

The products can be either gaseous or solid components (or both). The kinetics of the reaction is defined according to the available particle surface area  

FIGURE 8.4 Particle structures according to the grain model. (Data from Ranz, W.E. and Marshall, W.R., Chem. Eng. Prog., 48,141-173,1952.) 

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