GC030 The Achievement of Separation

To analyze of the separation of two peaks is achieved, the following equation is used:

Rs = d / Wb

Where Rs is the resolution, d Is the distance between the maxima of two adjacent peaks and Wb is the peak width. Peak width, Wb, increases as the square root of the column length, L, and d increases directly with L. In other words

Rs is proportional to L / L^(1/2) = L^(1/2)

Resolution is proportional to the square root of the column length.

If we plot d or Wb versus L, d will surpass Wb at a sufficient large value of L and the separation is achieved. The conclusion is that the chromatographic process in effective even if it produces peak broadening. Of course, in practice there are many methods to achieve a separation and the analyst rarely relies only in the column length.

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