Thermogravimetric analysis (TGA) is an official method used to determine the moisture content of a substance. TGA measures the mass of a sample as it is heated or cooled, providing valuable insights into the material’s thermal stability and composition.
Principle of TGA
TGA operates on the principle of mass change measurement. A known sample mass is placed in a controlled heating or cooling environment, and its weight is continuously monitored. As the sample undergoes thermal decomposition, dehydration, or other mass-altering processes, its mass changes.
Applications of TGA
TGA finds numerous applications in various fields, including:
- Moisture Content Determination: TGA is used to determine the moisture content of materials by measuring the mass loss due to water evaporation during heating.
- Thermal Stability Assessment: TGA provides information about the thermal stability of materials by monitoring mass changes associated with decomposition or phase transitions.
- Organic Matter Content Analysis: TGA helps determine the organic content of samples by measuring the mass loss due to combustion or pyrolysis.
- Pharmaceutical Analysis: TGA is utilized to study drug-excipient interactions, stability, and purity.
Advantages of TGA
TGA offers several advantages:
- High Sensitivity: TGA can detect mass changes as small as micrograms.
- Real-Time Monitoring: TGA provides continuous data acquisition during heating or cooling.
- Wide Temperature Range: TGA can analyze samples at temperatures ranging from ambient to over 1000°C (limited by instrument capabilities).
- Versatile: TGA can analyze a wide variety of materials in various forms (solid, liquid, or gas).
Conclusion
Thermogravimetric analysis (TGA) is a valuable technique for determining the moisture content and other mass-related properties of materials. With its high accuracy, real-time monitoring, and versatility, TGA plays a crucial role in numerous scientific and industrial applications.