3-1. Optimal Linear Velocity
For the same packing material (support material and particle diameter), the optimal linear velocity is almost independent of the column I.D. and comparable plate numbers are yielded.
3-2. Sample Loading Capacity
The increase in the column I.D. increases the flow rate to keep the linear velocity optimal, but it also increases the sample loading capacity. For example, the increase in the sample loading capacity is proportional to the increase in the column I.D. when the linear velocity remains constant. By using a small I.D. column for preliminary experiments, the sample loading capacity of larger I.D. columns can be estimated.
3-3. Proportionality of the Flow Rate and the Sample Load to the Cross-sectional Area
By proportionally increasing the flow rate and the injection volume (constant sample concentration), similar chromatograms can be obtained among different I.D. columns packed with the same packing material.