What is TGA ?
Thermogravimetric analysis (TGA) is the mass loss or gain in a sample as a function of temperature and time under controlled atmospheric conditions. More simply, TGA measures the mass lost or gained as a sample is heated according to a predefined program of temperature and time. Traditionally samples are placed into laboratory ovens and muffle furnaces for fixed times and usually at fixed temperatures. Samples are subsequently weighed manually. LabFit’s TGA units with integrated load cells combine drying, ashing and weighing processes. This drastically improves efficiency, precision and accuracy, and sample throughput.
LabFit TGA’s determine data such as such as moisture content, loss or gain of ignition, loss of volatiles, oxidation, pyrolysis, plasticizer loss, and ash content. The TGA’s are suitable for a wide range of materials such as ores, coal, coke, cement, lime, polymers, adhesives, foodstuffs, pharmaceuticals, chemicals, paper, tobacco and organic samples.
Typically the analysis is performed in air, but other gases such as nitrogen or oxygen can be used to achieve a specific test atmosphere. Samples can be heated and cooled to specific heating profiles. The heating rates can be set to each temperature. Samples can be held at fixed temperatures for a predefined period of time or samples can be constantly weighed at predefined temperatures until they reach constant mass.
LabFit TGA’s are used to analyses samples in accordance with several international standards such as ISO and/or ASTM standards
The Apollo L is a variant of the standard Apollo TGA. It is identical in most aspects, except it features a second carousel which holds lids for the sample crucibles. These can be automatically placed and removed during the analytical process with no need for operator intervention.
It accommodates up to 20 samples of 5 grams each, and can heat them to 1000 °C in a user-defined atmosphere. Some applications such as ASTM methods for the determination of volatile matter or other very reactive sample types requires that the crucibles are covered with lids. The double carousel allows the operator to setup predefined methods and select when in the cycle to lift the lids or when in the cycle lower the lids to seal the crucibles.
The software allows for weighing of the crucibles with or without the lids on. This level of flexibility allows the operator to setup analytical programs to suit most known TGA methods.
Examples include ASTM – methods for the measurement of moisture, ash and volatile matte
|Sample Mass||<5g ( Up to 70 g for special applications)|
|Number of samples||20|
|Number of carousels||2 (Crucible + lids)|
|Balance Resolutions||0.1 mg|
|Temperature Range||Ambient to 1000°C|
|Temperature Control||Precision : 2% or ± 2°C / stability : 2% or ±2°C|
|Gas Flow Rate||Adjustment from 1 to 10 L/min|
|Gas Pressure||Air 5-6 Bar (75-90 psi) / Nitrgoen 2-4 Bar (30-60 psi)/ oxygen 2 – 4 bar (30 – 60 psi)|
|Exhaust Air||4 m³per hour|
|Power Supply||230 V (±10%) / one phase / 50/60 Hz / 15 A (TGA’s)
230 V (±10%) / one phase / 50/60 Hz / 2 A (PC, fan)
|Dimensions||603 x 674 x 577 mm|
|Accessories||computer, monitor, printer|