CHOICE OF REACTOR

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CHOICE OF REACTOR

• REACTION PATH
• TYPE OF REACTION SYSTEM
• REACTOR PERFORMANCE
• IDEAL REACTORS
• REACTANTS CONCENTRATIONS
• REACTOR TEMPERATURE
• REACTOR PRESSURE
• REACTOR PHASE
• CATALYSTS

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CHOICE OF REACTOR
REACTION PATH

• Given a set of possible reaction paths for the
  desired product
• Economics (Value of Products-Raw Material Cost)
• Type of byproducts (minimize waste)

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CHOICE OF REACTOR
TYPE OF REACTION SYSTEM

• Single Reaction
• Multiple Reactions in Parallel
• Multiple Reactions in Series
• Mixed type
• Polymerization

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CHOICE OF REACTOR
REACTOR PERFORMANCE

• Polymerization distribution of molecular weights
• Other Reactions
• ConversionReactant consumed/Reactant fed
• Selectivity(Desired Product produced/Reactant
  Consumed)Stoichiometric Factor
• Yield (Desired Product produced/Reactant
  Fed)Stoichiometric Factor

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CHOICE OF REACTOR
REACTOR PERFORMANCE

• If more than one reactant focus on more
  expensive one.
• Reversible Reactions Maximum Conversion possible
  Equilibrium Conversion.
• Maximum Selectivity
• Raw Materials wasted
• Environmental Problem

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CHOICE OF REACTOR
REACTOR PERFORMANCE

• Single Reactions
• Goal Minimize Capital Cost
• Minimize the reactor volume.
• Rule 95 conversion for irreversible reactions
• or 95 of the equilibrium conversion

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CHOICE OF REACTOR
REACTOR PERFORMANCE

• Multiple Reactions in Parallel
• Goal Maximize Selectivity
• Initial Settings
• If S ? as Conv. ?, then 95 rule
• If S ? as Conv. ?, then 50 rule

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CHOICE OF REACTOR
REACTOR PERFORMANCE

• Multiple Reactions in Parallel
• Example

S ? as Conv. ?
S ? as Conv. ?
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CHOICE OF REACTOR
IDEAL REACTORS
Single Reactions

• Goal Minimize the volume
• CSTR Not the best choice

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CHOICE OF REACTOR
IDEAL REACTORS
Multiple Reactions in Parallel
Goal Maximize Selectivity CSTR If Batch or
Plug Flow if
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CHOICE OF REACTOR
IDEAL REACTORS
Multiple Reactions in Series
Goal Maximize Selectivity CSTR Not a GOOD
CHOICE
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CHOICE OF REACTOR
IDEAL REACTORS
Multiple Mixed Reactions
Batch or Plug Flow if
Need a combination of reactors
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CHOICE OF REACTOR
IDEAL REACTORS
Polymerization

• P.F. or Batch No termination reactions /
  active life is long compared to residence time.
• CSTR Active life is short compared with
  average residence time Constant concentration
  of monomer which means a constant termination
  rate.

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CHOICE OF REACTOR
REACTOR CONCENTRATION
Single Irreversible Reaction
Rule Reactant in excess minimize the outgoing
flow of the component more difficult to separate
downstream.
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CHOICE OF REACTOR
REACTOR CONCENTRATION
Single Reversible Reaction

• Rule Le Chateliers Principle applies
• Increase Feed
• Introduce an inert
• Remove a product
• Vaporize from a liquid-phase reactor
• Reaction in stages

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CHOICE OF REACTOR
REACTOR CONCENTRATION
Multiple Reactions in Parallel
Excess F2
Excess F1
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CHOICE OF REACTOR
REACTOR CONCENTRATION
Multiple Reactions in Parallel
Introduce and/or increase inert concentration
Reduce inert concentration
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CHOICE OF REACTOR
REACTOR CONCENTRATION
Multiple Reactions in Series
Possible solutions

• Use
• Recycle the Diphenyl