Column Elution: Elution Strategy Tab

This tab appears on the interface dialog of the following operation:

Variable Definitions, Ranges and Default Values

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

Variable	Default Value	Range

○ Key Component Name Indicates a valid component of the feed stream, for which reference initial and final concentration values in the gradient elution buffer are specified. Click on the list box to bring up a list of registered pure components in order to select one component as the key component.	<none>	Any Comp.
○ Initial Concentration Of Key Component (g/L) The initial concentration of the key component in the gradient buffer.	0.0	Positive
○ Final Concentration Of Key Component (g/L) The final concentration of the key component in the gradient buffer.	0.0	Positive
○ Initial Volume of Eluant (A) (%) The initial volume of eluant (A) in the gradient buffer.	0.0	Positive
○ Final Volume of Eluant (A) (%) The final volume of eluant (A) in the gradient buffer.	0.0	Positive
○ Eluant (A) Inlet Stream Indicates the input port that is connected to the first eluant stream. If an input stream is already present at the selected port, then the button next to the selection is active. Click on the button to bring up the attached stream’s simulation dialog in order to provide the composition of the material being charged.	In #1	Any Input Port
● Eluant (A) Volume per Cycle, per Unit (L) The volume of the first eluant stream per cycle and per equipment unit.	0.0	Positive
○ Eluant (B) Inlet Stream Indicates the input port that is connected to the second eluant stream. If an input stream is already present at the selected port, then the button next to the selection is active. Click on the button to bring up the attached stream’s simulation dialog in order to provide the composition of the material being charged.	In #2	Any Input Port
● Eluant (B) Volume per Cycle, per Unit (L) The volume of the second eluant stream per cycle and per equipment unit.	0.0	Positive

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

Specification Choices / Comments

The following list describes the available specification choices in this tab; for more details on how these are implemented, see Column Elution: Modeling Calculations.

•Gradient Elution...

For gradient elution, the gradient buffer is generated by mixing two different buffers in continuously varying ratios. In that case, you need to identify the two buffer (eluant) streams (A and B) and specify either the initial and final concentrations of a “key component” in the gradient buffer, or the initial and final volumes of buffer “A” in the gradient buffer. Based on these, the program will calculate the volumes of the two buffers.

When the initial and final concentrations of a key component are specified, these values must be between that component’s concentrations in the two buffers.

•Composition of Eluant Streams...

To specify the composition of an eluant stream, click on the Edit Composition button next to the stream selection box. That brings up the dialog of that stream and allows you to specify its composition. Please note that the flowrate of that stream will be adjusted by the elution model during simulation.