The thermal characterisation facilities, have provided a thermal analysis service to industry for well over two decades. The Laboratory possesses a range of thermal analysis equipment capable of analysing materials which range from cements to polymers and from minerals to phase change materials over temperatures ranging from -50 to 1500 °C.
- Thermogravimetric Analysis (TGA) measures mass change as a function of temperature
- Differential Thermal Analysis (DTA) measures thermal events occurring during a controlled heating program
- Differential Scanning Calorimetry (DSC) enables thermal events and heat capacity changes to be measured sensitively and quantitatively
- Simultaneous Thermal Analysis (STA) is a combination of TGA and either DTA or DSC
- Evolved Gas Analysis (EGA) enables gases and vapours produced during thermal analysis to be analysed by infra-red analysis or mass spectrometry.
The range of materials which can be characterised by thermal analysis is large and continues to increase. Consequently we have provided a service to a number of significant Western Australian industries including producers of cement, alumina, pigments, ceramics, nickel, gold, pharmaceuticals, polymers and heat storage liquids as well as to consultant engineers and chemists.
Some Applications of Thermal Analysis
- Activated Carbon used in the C.I.P. process of gold extraction becomes fouled and needs regenerating. TG analysis displays mass loss v temperature. The presence and amount of adsorbed foulants may be deduced and the optimum regeneration temperature determined
- Calcium Sulphate Hydrates in cement may be estimated. Gypsum (CaSO4.2H2O) and CaSO4.½H2O decompose when heated to just over 100 °C. DSC analysis of this endothermic decomposition is used to estimate the proportions of the two hydrates
- Composition of Rubber may be determined using TGA. By controlling the atmosphere used during a TGA run the polymer, carbon black and filler composition can be quickly determined
- Quantitative Analysis of Minerals such as gibbsite, clays, carbonates, sulphide, etc. is possible by determining the mass loss over the mineral’s characteristic decomposition temperature range
- Gases Evolved during TG analysis may be analysed by infra-red or mass spectrometry (a technique known as TG-EGA). This can be used to help identify a material or the thermal stability of a compound
- The Cure of Thermosetting Resins may be investigated using DSC analysis. Use can be made of the exothermic curing reaction or the glass transition temperature to provide useful information.
These are merely a sample of thermal analysis applications developed. Any material which undergoes a change of mass, energy or appearance during a controlled thermal program can, theoretically, be analysed by thermal methods.