THERMOGRAVIMETRIC ANALYSIS

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 THERMOGRAVIMETRIC ANALYSIS

  • It is a thermal analytic technique in which the mass of a substance is measured as a function of increasing temperature.
  • As the temperature increases, the sample undergoes physical and chemically changed will be accompanied by mass loss. 
  • It is used to determine a material’s thermal stability and its fraction of volatile components by measuring the weight change. 
  • It is carried out in air or inert atmosphere such as nitrogen, helium, or Argon. 
  • The graph obtained is known as a thermogram.
  • It is a plot of mass vs temperature.
  • It can provide information about physical phenomena such as vaporization, sublimation. Absorption, adsorption, and desorption.
  • And chemical phenomena like chemisorption, dehydration, decomposition, oxidation, and reduction. 


WORKING OF TGA

  • The sample is placed in a crucible or shallow dish that is attached to an automatic recording balance and is continuously heated by the power source.
  • The weight change of the sample is converted into an electronic signal and recorded at different temperatures in the Y-axis of the recorder,
  • The furnace temperature is continuously monitored by a thermocouple whose signal is applied to the X-axis of the recorder.
Location: United States

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