High performance liquid chromatography column packings with deliberately broadened particle size distribution:...

Area of Science:

• Chemical Engineering
• Materials Science

Background:

• Particle size distribution significantly impacts packed bed column performance.
• Optimizing packed beds requires understanding particle interactions and packing structures.

Purpose of the Study:

• To investigate the effect of adding larger particles (3 and 5 μm) to a commercial batch of 1.9 μm particles.
• To analyze the influence of varying particle size distributions on the kinetic performance of packed bed columns.

Main Methods:

• Experimental investigation of packed bed column performance with different particle mixtures.
• Computational packing simulations to analyze packing structure.
• Experimental determination of external porosity.

Main Results:

• Addition of larger particles generally deteriorates kinetic performance.
• Mixtures with 50% or 75% larger particles showed significantly worsened performance, with separation impedance increasing up to 200%.
• Small particles settled in pores around larger particles, increasing packing density and negatively affecting permeability and band broadening.

Conclusions:

• The addition of larger particles to smaller particles in packed beds is detrimental to kinetic performance.
• Understanding packing structure and porosity is crucial for predicting column performance.
• Optimal packed bed design requires careful consideration of particle size distribution.