Balance Calculations for Recycle Reactors

Adapted with permission from original in Catal. Rev.-Eci. Eng., 20, 1, pp. 75-95, 1979 Marcel Dekker. 

The inner balance accounts for the chemical changes over the W kg catalyst by expressing the difference between the large flow times the small concentration change from in to out over the catalyst bed. 

The outer balance gives the overall change between the outside boundaries of the RR system. The chemical change that occurred over the W kg catalyst is now expressed as the difference between the small flow times the large concentration change between in and out of the RR system. 

If chemical reactions occur only over the catalyst and none on the walls or in the homogeneous fluid stream in the recycle loop, then conservation laws require that the two balances should be equal. 

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