Gas Chromatography Detectors - Detector Linearity > Determination of Response Index > The Logarithmic Dilution Method of Linearity Measurement > Page 8

The Logarithmic Dilution Method of Linearity Measurement

This method of linearity measurement was introduced by Lovelock (2). The procedure requires some special apparatus that is diagramatically represented in figure 3.

Figure 3 The Logarithmic Dilution Apparatus.

A known mass of solute is introduced into a well–stirred vessel through which passes a flow of gas. The exit gas is arranged to pass directly into the detector. As a consequence, the mixture is continuously diluted and the concentration of the solute in the exit flow continuously monitored by the detector.

 

Let a volume (dv) of pure solvent enter the vessel (volume V) and displace a similar volume (dv) from the vessel.