Determination of the Loading Capacity

After the conditions for the enantiomer separation have been optimized, the loading (injected amount) on the analytical column (16-20 gm particle size) is increased in order to determine the maximum amoimt that will still guarantee the desired purity and recovery. With the assumption that a pilot-scale column shows an identical efficiency to an analytical column, the loading can be determined according to Eq. (11)  

Mp is the maxunum amount that can be separated on a pilot scale and Ma is the optimized amount obtained from the overloaded injections. Lp and La are the lengths of the pilot and analytical columns, respectively dp and (1a represent the inner diameters of the two columns. The maximum loading factor is constant. In order to increase the amount that can be separated with a single injection, it is useful to select a column with a larger inner diameter. The often (erroneously) chosen increased bed length does indeed increase the maximum separable amount, but it inevitably leads to an increased back-pressure, longer retention times, and results in a lower productivity. 

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