van Deemter Equation

$H = A+(B/u_x)+C*u_x$

Enter a value for all fields

The van Deemter calculator use the van Deemter equation to compute height of the place dependent on the flow rate and the column in chromatography.

INSTRUCTIONS: Enter the following:

(A) This is a constant for multiple paths
(B) This is a constant representing the longitudinal diffusion
(C) This is a constant for equilibration time
(u_x) This is the linear velocity in units of (mL/min)

Plate Height(H) The calculator returns the plate height in millimeters (mm). However this can be automatically converted to other length units via the pull-down menu.

The Science

The van Deemter Equation^[1] calculates the plate height which is dependent on the flow rate and the column in chromatography. Since chromatography deals with separations of mixed substances, a smaller plate height yields better separations.

The Math

The van Deemter equation is

$H ~= A + B/U_x + Cu_x$

where:

A is a constant for multiple paths
B is a constant representing the longitudinal diffusion
C is a constant for equilibration time
u_x is the linear velocity in units of (mL/min)
H is the plate height in units of (mm)

References

Harris, 9th Edition. Pp.622

[1] For the Spanish site click here