Chromatography detector

The flame photometric detector ( FPD) is a detector for phosphorus and sulfur compounds, mostly in conjunction with the gas chromatograph (GC ), or is used as a fire detector.

Principle of measurement

The FPD uses during the combustion of phosphorus and sulfur compounds released light of certain wavelengths. The combustion of the substance occurs as the flame in an oxyhydrogen flame. The thus excited sulfur and phosphorus atoms emit light having a characteristic wavelength ( 394 nm and 526 nm for sulfur phosphorus).

Technical use

Fire alarm

The first flame photometric detector ( FPD) was developed in the 1950s by DW Grant. The selective measurement is done with an appropriate filter by a photomultiplier tube. One FPD is very sensitive and works selectively. The principle is considered the best sulfur detector.

GC detector

In the 1960s, then the coupling GC / FPD was developed. The detection is carried out when used as a GC detector, also by means of a photomultiplier with an upstream filter. The detection limits for phosphorus at about 10 pg, sulfur they are> 100 pg. The detector has a non-linear response to sulfur.

With the FPD can be detected with appropriate filters and halogenated hydrocarbons and organotin compounds. A further development of the FPD is the PFPD ( Pulsed Flame Photometric Detector)