Reaction Kinetics Dialog

RxnKineticsDlg.jpg

This dialog appears when you click on the reaction kinetics button rxnKint00155.bmp from the reaction tab of the following operations:

●      Batch Kinetic Reaction

●      Continuous Kinetic Reaction

●      Continuous Kinetic Reaction in a Plug Flow Reactor (PFR)

Variable Definitions, Ranges and Default Values

The following table shows a brief description of the variables appearing in this dialog. The table also displays their default values and their generally acceptable range:

Variable

Default Value

Range

 

○ Reaction Order Exponent
For each reacting component the reaction order exponent is set.

0.0

Any Number

○ Rate Reference Component
The component that the rate is calculated for.

(none)

Compo-nent

Inhibition Terms:

 

 

○ K1 (kmol/m3)
User specified constant

1.0

Any Number

○ K2
User specified constant

1.0

Non-Zero

○ Species (m)
Pure component identified as m.

(none)

Compo-nent

○ Species (n)
Pure component identified as n.

(none)

Compo-nent

Rate constant (k) specification:

 

 

○ Options
Rate constant (k) may be either specified by the user or calculated from the Arrhenius equation (k = A*exp(-E/RT))

Set by User

Set / Calc

○ Frequency Factor (A)
Pre-exponential frequency factor.

0.0

Positive

○ Activation Energy (E) (kj/kmol)
Molar energy activation factor.

0.0

Positive

Symbol Key: ○ User-specified value (always input); ● Calculated value (always output); ◙ Sometimes input, sometimes output

Specification Choices / Comments

The following describes the available specification choices in this dialog; for more details on how these are implemented, please view see Batch Kinetic Reaction: Modeling Calculations.

Only components with a non-zero exponent affect the kinetics of the reaction. The calculated rate of the reaction is for the Rate Reference Component.

 

Inhibition Terms

If a reactant or product inhibits the reaction, it can be represented by specifying appropriate values for the inhibition terms.

Rate Constant (k)

The reaction rate constant can be specified by the user or calculated based on the Arrhenius equation. In the latter case, the user must provide the Frequency Factor (A) and Activation Energy (E) of the reaction.

Finally to add Start / End Criteria for a reaction press on corresponding button and a new dialog Reaction Kinetics: Start / End Criteria Dialog appears enabling you to set these options. Start & End criteria can only be set for batch reaction operations.