Thermogravimetry/Evolved Gas Analysis (TG-EGA)

Thermogravimetry/Evolved Gas Analysis (TG-EGA)

TG-EGA is a hyphenated technique for simultaneous thermo-gravimetric and chemical analysis of a sample. Thermogravimetric analysis is performed using a Thermogravimetric Analyzer (TGA) or Thermobalance, to continuously measure the change in mass of a sample subjected to a controlled heating program. The reduction in mass occurs due to the evolution of gases (including volatile molecules), during processes such as evaporation, decomposition or outgassing of inclusions. In the TG-EGA method, the evolved gases are simultaneously routed to an Evolved Gas Analysis (EGA) system. The EGA system can utilize a variety of techniques such as Fourier Transform Infrared spectroscopy (FTIR), Mass Spectrometry (MS) or combination of MS with gas chromatography (GC-MS). This enables identification of the evolved gas components and real time correlation with the mass change data from TGA. TG-EGA enables chemical fingerprinting of the volatile components and thermal decomposition products of a sample, along with a real-time, mass balance.

Common Uses of TG-EGA

• Analysis and characterization of natural resources such as coal, rocks and minerals
• Analysis of thermal behavior and chemical composition of synthetic polymers
• Analysis of Petroleum coke and waste sludge from Refinery and petrochemical plants
• Study of Chemical reactions involving evolution of vapors
• Adulteration detection in Foods
• Residual solvent measurements in Pharmaceuticals
•  Forensic analysis

Advantages of TG-EGA

• High Sensitivity
• Compositional, mass balance and thermogravimetric information can be measured in real-time.  
• Low sample quantity.
• Wide heating temperature range and variety of materials can be analyzed
• Qualitative and quantitative analysis possible

 Limitations of TG-EGA

• Complicated for unstable materials

Industrial Applications of TG-EGA

• Fossil fuels
• Geology and Mineralogy
• Plastics, Polymers, Rubber
• Pharmaceuticals
• Chemicals and Petrochemicals
• Petroleum
• Food
• Biomass
• Environmental