Separation Window Diagrams for High-Speed GC

Abstract

The use of window diagrams for multicolumn optimization in high-speed GC is considered. The distinguishing feature of high-speed GC is the frequent use of low capacity factor values to minimize separation time and maximize the rate of production of theoretical plates. Plots of critical pair relative retention versus column length fraction of either column have previously been used to identify the best separation conditions. For small capacity factor values, relative retention is not a good measure of separation. An alternative separation parameter, relative resolution, is compared to relative retention for optimization of low-capacity-factor separations. This parameter preserves the convenience of requiring only capacity factor values. Application to high-speed separations is illustrated.