Plate number column diameter reduction

The major reason why a reduction of the particle size or column diameter is expected to lead to an increase of separation speed (resolution power per time unit) can be found in its effect to decrease r. Separation speed is often expressed in the analytical literature in terms of the number of theoretical plates N per time unit f (for a definition of N in terms of experimental parameters see Sect. 3.1.1). For zone dispersion due to lateral non-equilibrium, the ratio N/t will be in general inversely proportional to r [20] ... 

The obvious advantages of a reduction of the column diameter in analytical enantioseparations include less consumption of packing materials and of high-purity organic solvents, less environmental problems, smaller sample size, and improved analytical characteristics (less dilution of sample, higher plate number and shorter analysis time) of the separation [120]. 

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