Pore mouth closure

Q%ere remains an uncoked central core, apparently never contactec by reactant. 35ie work of Rostrup-Nielsen 5 and Levintner 6 also suggests that pore mouth closure by coke plugs may be theoretically required, and a simplified theory has been recently proposed by Newson ... 

The discrimination of the correct deactivating mechanism is of more than academic importance. Thus, if in a particular case, as here, pore mouth plugging is the most important deactivating mechanism, attention should be concentrated on changing the physical pore structure of the catalyst in order to alleviate the deactivation. The striking of a correct balance between poisoning and fouling pore mouth closure when they are both... 

At the instant of pore mouth closure e becomes zero. For this case Eq.2.56 takes the following form ... 

One has to look the catalyst into its pore mouth in order to tell its age. With a fresh catalyst the pore mouth is fully open and 0=0. As soon as 0 = 1, the catalyst has obviously died through complete closure of the "diaphragm" of metal deposits. 

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