The optimization strategies for space time (yield)

The strategy depends on the 'essence' of the chemical reaction

• Let us call a first type of reactions 'simple reactions', where the rate and quantity of our product formed from the educt is linked only to the conversion ( i.e. directly and in a steady function). Here we have to chose only a very high conversion and a contacting pattern, which provides an optimal space time. (Remember: in this case an optimal space time can be reached in reactors without back-mixing (i.e. not back-mixed in both space and time): batch reactor and tubular flow reactor. Can you explain this statement? - No? )
  We can call this optimizing strategy:
  'conversion orientated strategy'
  (german: 'Umsatzorientierte Strategie')
  
  
• The second type of reaction is the more 'complex' type, where the product formation is not simply linked to the conversion of educt(s). All sorts of complex reaction networks are belonging to this type. Very often selectivity problems are encountered as a consequence of several (possible) reaction paths. Comprehensive examples are simple parallel (snapshot) and consecutive (snapshot) as well as autocatalytic reactions. Examples and further details will be given in later questions and in various simulations. In the case of these 'complex' reactions we are forced to maintain required concentration levels in 'specific volume parts' at 'specific times'. We have to optimize space time yield by controlling concentration levels. This process is of course more complicated, but in general the optimization process can be carried out by using the possibilities of the choice and adjustment of the contacting pattern, i.e. (as we call it) the macro-mixing conditions. We can use a variety of reactor combinations to reach a desired contacting pattern. The local degree of back-mixing is the important item.
  We can call this optimizing strategy:
  'strategy of controlling concentration levels'
  (german: 'Konzentrationsführungs - Strategie')
  
  
• Summary on the optimization
  
  
• Last not least it should be kept in the mind that the influence of temperature and catalysts provides very powerful tools for the enhancement of product yields.

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