Figure 1.3.1
: 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
500 795/Rev E/03-17
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