Chemical Instrumentation

Flame Atomic Absorption Spectrometry

  • Flame Atomic Absorption is a very common technique for detecting metals present in samples.
  • The technique is based on the principle that ground state metals absorb light at a specific wavelength.
  • Metal ions in a solution are converted to atomic state by means of a flame.
  • When light of the correct wavelength is supplied, the amount of light absorbed is measured and a reading for concentration can be obtained.
  • Flame atomic absorption is a very accurate quantitative technique and also a good qualitative technique.
  • This is one of the main reasons it is the most widely used of the atomic absorption methods.

Flame Atomic Absorption Spectrometer

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  • The set up for most Flame atomic absorption spectrometers are relatively simple in design.
  • The most complicated part of the instrument is the nebuilzer.
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Flame Atomic Absorption Spectrometer

Nebulizer

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  • The nebuilzer system is highly important in FAAS.
  • The nebuilzer converts the sample solution into a mist or aerosol.
  • The nebulized sample is then carried into the flame.

Process of Flame Atomic Absorption Spectrometer

  • Radiation from the specific light source is focused on the atomic vapor in the flame. 
  • The radiation then enters a monochromator, which isolates the line of interest.
  • The light is then measured by a photomultiplier tube (detector). 
  • The signal is then processed and the computer system prints the output on screen. 

Uses of Flame Atomic Absorption Spectrometry

  • Flame Atomic Absorption Spectrometry is a sensitive technique for the quantitative determination of more than sixty metals.
  • As it is used for determining the concentration of metals it can be applied in Environmental Analysis.
  • It can also be used to detect if there is trace metals present in food.