A New Slurrypacking Technique for Columns in High-Speed Liquid Chromatography

Abstract
In this work a new packing principle was investigated, which involves a combination of stirring action to keep the particles floating and high initial pressure action to transport the particles rapidly from the mixing vessel via high pressure tubing into the column. This packing technique can provide good columns at lengths <20 cm. Shorter columns could be coupled easily to increase the plate number but for most practical applications the separation efficiency is satisfactory. The column quality is comparable to columns packed by the equal density method but the technique has several advantages, such as shorter packing time (3 columns in 15 minutes compared to about 4 hours with the former technique); absence of toxic halogenated solvents and tedious adjustment of adsorbents. The technique is flexible and has been used for 5μ, 7μ, and 10μ silicagels of two manufacturers. Alumina 10μ, and Kieselgur 10μ have also been packed satisfactorily. From the results with the chemically bonded phase ETH-Du Pont, it can be concluded that other chemically bonded phases on 5μ or 10μ particles can be packed without damage. The technique is relatively inexpensive. The cost of the mixing vessel would be about 200 dollars. Preliminary tests have shown that for the packing of longer columns initial pressures of up to 500 atm in connection with a stronger mixing vessel design can be used.