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

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)

CHOICE OF REACTOR TYPE OF REACTION SYSTEM Single Reaction Multiple Reactions in Parallel Multiple Reactions in Series Mixed type Polymerization

CHOICE OF REACTOR REACTOR PERFORMANCE Polymerization: distribution of molecular weights Other Reactions: Conversion=Reactant consumed/Reactant fed Selectivity=(Desired Product produced/Reactant Consumed)Stoichiometric Factor Yield =(Desired Product produced/Reactant Fed)Stoichiometric Factor

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

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

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

CHOICE OF REACTOR REACTOR PERFORMANCE Multiple Reactions in Parallel Example: S  as Conv.  S  as Conv. 

CHOICE OF REACTOR IDEAL REACTORS Single Reactions Goal: Minimize the volume CSTR : Not the best choice

CHOICE OF REACTOR IDEAL REACTORS Multiple Reactions in Parallel Goal: Maximize Selectivity CSTR : If Batch or Plug Flow: if

CHOICE OF REACTOR IDEAL REACTORS Multiple Reactions in Series Goal: Maximize Selectivity CSTR : Not a GOOD CHOICE

CHOICE OF REACTOR IDEAL REACTORS Multiple Mixed Reactions Batch or Plug Flow: if Need a combination of reactors

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.

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

CHOICE OF REACTOR REACTOR CONCENTRATION Single Reversible Reaction Rule: Le Chatelier’s Principle applies Increase Feed Introduce an inert Remove a product Vaporize from a liquid-phase reactor Reaction in stages

CHOICE OF REACTOR REACTOR CONCENTRATION Multiple Reactions in Parallel Excess F2 Excess F1

CHOICE OF REACTOR REACTOR CONCENTRATION Multiple Reactions in Parallel Introduce and/or increase inert concentration Reduce inert concentration

CHOICE OF REACTOR REACTOR CONCENTRATION Multiple Reactions in Series Possible solutions: Use Recycle the Diphenyl