
5
PFP7/REV C/01-08
Figure 1.2.1
: Schematic diagram showing the component parts of a flame photometer.
The analysis of alkali and alkaline earth metals by flame photometry has two major advantages:
i.
Their atoms reach the excited state at a temperature lower than that at which most
other elements are excited.
ii.
Their characteristic wavelengths are easily isolated from those of most other elements
due to wide spectral separation.
The analysis of Na, K, Li, Ba and Ca are typically determined at low temperatures, i.e. 1500-
2000°C, therefore suitable fuel mixtures are propane/air, butane/air and natural gas/air.
Burner
Nebuliser
Mixing chamber
Filter
Flame
Photodetector
Gas inlet
Drain
“U” tube
Waste
Readout
Amplifier
Lens
Air inlet
Burner
Nebuliser
Mixing chamber
Filter
Flame
Photodetector
Gas inlet
Drain
“U” tube
Waste
Readout
Amplifier
Lens
Air inlet