Effect of particle size distribution on the separation efficiency in liquid chromatography

• Influence of the width of particle size distribution (PSD) on chromatographic efficiency is studied.
• A theoretical framework is developed in order to calculate this effect.
• Wide particle size distributions have significant effect on the separation efficiency.
• Bimodal packings do not have any advantage over unimodal phases.

In this work, the influence of the width of particle size distribution (PSD) on chromatographic efficiency is studied. The PSD is described by lognormal distribution. A theoretical framework is developed in order to calculate heights equivalent to a theoretical plate in case of different PSDs. Our calculations demonstrate and verify that wide particle size distributions have significant effect on the separation efficiency of molecules. The differences of fully porous and core–shell phases regarding the influence of width of PSD are presented and discussed. The efficiencies of bimodal phases were also calculated. The results showed that these packings do not have any advantage over unimodal phases.