flow rate in chromatography

The volume of mobile phase passing through the column in unit time. The flow rate is usually measured at column outlet, at ambient pressure ( $p a$ ) and temperature ( $T a$ , in $K$ ); this value is indicated with the symbol $F$ . If a water-containing flowmeter was used for the measurement (e.g. the so-called soap bubble flowmeter) then $F$ must be corrected to dry gas conditions in order to obtain the mobile phase flow rate at ambient temperature ( $F a$ ):

$F a = F ( 1 − p w p a )$

where $p w$ is the partial pressure of water vapour at ambient temperature. In order to specify chromatographic conditions in column chromatography, the flow-rate (mobile phase flow rate at column temperature, $F c$ ) must be expressed at $T c$ (kelvin), the column temperature:

$F c = F a T c T a$

Source:

PAC, 1993, 65, 819 (Nomenclature for chromatography (IUPAC Recommendations 1993)) on page 839