Type III isotherms

Again, this was for isothermal conditions. In non-isothermal Type III reactions, a deviating temperature will also impose additional effects on selectivity, once the activation energies of the two reactions differ sig-... 

Figure 7.13 Differential and overall selectivities in an isothermal Type III reaction with both interphase and intraphase gradients. [After J.J. Carberry, Chem. Eng. Sci., 17, 675, with permission of Pergamon Press, Ltd., London, England, (1962).]...

There is a more fundamental classification of adsorption isotherms according to Bmnauer, which divides the adsorption isotherms into five types. Type 1 is the monolayer chemical Langmuir-type adsorption and type II is the multilayer physical BET adsorption isotherm. Type III is for - rather rarely occurring - weak adsorptions and types IV and V are for capillary condensation. There are, however, some adsorption isotherms that do not fit into Bmnauer s classification. 

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