Semi-Batch Reactors Flashcards
Describe a semi-batch reactor.
Similar to a batch reactor as it is perfectly mixed, but it is filled during operation. One or more reactants is added initially, and then one or more reactants are also added continuously.
Explain the advantages of semi-batch reactors.
An increase in the production of the desired products, and limit the amounts of by-products (by-products may be harmful or just reduce the yield).
State 3 special cases in which a semi-batch reactor may be used.
- for highly exothermic reactions
- where one reagent is a gas
- distillation where the reagents are added simultaneouslt but the product is removed continuously
If R is the desired product, and A+B makes R, but R+B makes S, draw the graph representing the concentrations of each component if A is added slowly to B.
If R is the desired product, and A+B makes R, but R+B makes S, draw the graph representing the concentrations of each component if B is added slowly to A.
Describe a semi-PFR reactor.
One reagent is already in the reactor, and the other is added at intervals along it. The concentration of the reagent added at intervals will therefore remain relatively high, while the concentration of the reagent inside the reactor begins high but declines.
