Thermogravimetry is a standard method to analyze organic, inorganic and synthetic materials. Thermogravimetric analysis in general means the measurement of the weight loss during a user-defined temperature or heating process.ELTRA’s TGA Thermostep is a thermogravimetric analyzer which determines various parameters such as moisture, volatiles and ash at user-defined temperatures and atmospheres in a single analysis. The thermogravimetrics analyzer TGA Thermostep simultaneously analyzes up to 19 samples with sample weights up to 5 g and can be operated at temperatures up to 1000 °C.
A special feature of the TGA Thermostep is the management of crucible covers. The thermogravimetric analyzer can place and remove the covers of the crucibles during analysis. This feature allows for example the precise determination of volatile content in coal and coke.
BENEFITS
- Measurement of up to 19 samples in one analysis
- Sample weights of up to 5 g
- Fast heating rates, accurate temperature control
- High-performance, precise weighing cell
- Automatic placing and lifting of crucible covers
- Robust design allows for use in laboratories and production
RELIABLE AND FLEXIBLE
ELTRA TGA analyzers are an ideal alternative to standard laboratory ovens and muffle furnaces for thermogravimetric analysis. Thanks to a programmable furnace that is connected to an integrated balance, heating and weighing are combined in one instrument. This saves time-consuming manual work and allows for high sample throughput. In addition, typical parameters such as moisture, ash and volatiles can be determined in one analysis run.
The TGA Thermostep processes up to 19 different samples, typically weighing between 500 mg and 5 g, in one analysis cycle. The surrounding atmosphere and temperature of up to 1,000 °C within the heating chamber can be freely defined by the user during analysis to create a standard operating procedure. The crucible lids, covering of the samples, can be raised or lowered at each stage of the analysis, thus allowing for safe and ASTM-compliant determination of volatiles in coal samples.
HIGH-PERFORMANCE ANALYSIS TECHNOLOGY
The TGA Thermostep is a powerful thermogravimetric analyzer characterized by robust design, high precision and flexibility. It is possible to apply different atmospheres and to use sample weights of up to 5 g. The Thermostep reliably and efficiently measures parameters such as moisture, ash and volatiles according to a user-defined SOP.
PURGING GAS
The TGA Thermostep is very flexible with regards to the purging gas used. At each stage of the analysis either nitrogen, oxygen or surrounding atmosphere can be selected. In the latter, the surrounding atmosphere penetrates into the TGA Thermostep, gently oxidizing the samples. | TEMPERATURE CONTROL
The furnace temperature is monitored by two thermocouples which are not encapsulated. One thermocouple monitors the temperature inside the furnace, the other monitors the temperature within the heating element. Due to the absence of the encapsulation the heating can be controlled quickly and precisely. | ENCAPSULATED WEIGHING CELL
The latest TGA Thermostep generation features an encapsulated weighing cell with 0.1 mg resolution providing highly precise measurements. The encapsulation isolates the weighing cell from the ambient atmosphere and is extremely stable. The weighing cell is connected to the furnace by a ceramic spindle with pedestal on which the crucibles are placed. |
HIGH-CAPACITY HEATING ELEMENTS 
| COOLING 
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SIMPLE OPERATION YIELDS QUICK RESULTS
Operation of the TGA Thermostep is simple, convenient and safe. After selecting the Standard Operating Procedure (SOP) in the PC, the sample ID’s can be entered into the software. The samples are then weighed in the crucible at the position assigned to the sample ID in the carousel. After one sample has been weighed, the carousel automatically rotates to the next position and the next registered sample can then be weighed in the crucible. Alternatively, a carousel filled with samples which has been weighed externally, can be placed into the analyzer.
It is also possible to position a second carousel with crucible lids above the crucibles. Once the analysis is finished, a new cycle can be started after a short cool-down period.
Weighing the sample 
| Option: Crucible lids 
| Display of analysis results 
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APPLICATIONS
Due to the flexible application management the TGA Thermostep can measure TGA parameters in many samples like coal, coke, building materials, food ...
ANALYSIS OF COAL & COKE The TGA Thermostep can determine the parameter moisture, volatile and ash in one analysis cycle due the automatic placing and removing of lids. The TGA is compliant to ASTM D 7582. | ANALYSIS OF BUILDING MATERIALS Building materials require the measurement of moisture and lost on ignition (LOI). The LOI can indicate the presence of organic matter or carbonates. | ANALYSIS OF FOOD Some foods like pet foods, bisquits, or milk require the measurement of dry mass and ash content. Due to the encapsuled weighing cell even the ash content of fluor could be measured safe and precise. |
TECHNICAL DATA
| Measured elements | ash content, moisture, volatiles |
| Samples | inorganic, organic, synthetic |
| Field of application | agriculture, biology, chemistry / plastics, coal / power plant, construction materials, environment / recycling, food, geology / mining, glass / ceramics, medicine / pharmaceuticals |
| Furnace | resistance heated ceramic furnace, programmable in 1 °C steps from 50 °C up to 1000 °C |
| Detection method | balance |
| Max. number of samples | 19 crucibles + 1 reference crucible |
| Balance resolution | 0.0001 g |
| Balance precision | 0.02 % RSD |
| Gas required | depends on application:
oxygen 99.9 % pure (2 - 4 bar)
and,or nitrogen 99.9 % pure (2 - 4 bar)
and air 99.5 % (5 - 6 bar)
|
| Power requirements | 230 V, 50/60 Hz, max. 32 A |
| Dimensions (W x H x D) | 55 x 52 x 62 cm |
| Weight | ~ 65 kg |
| Required equipment | PC, monitor, external exhaust (exhaust diameter: 100 mm / blower with 4m-3/min) |
FUNCTIONAL PRINCIPLE
Operation of the thermogravimetric analyzer TGA Thermostep is simple and convenient. The measurement process has to be defined once regarding the used temperatures, atmospheres and heating ranges. To start the thermogravimetric analysis, a predefined process simply has to be chosen in the software and the sample has to be weighed into the crucible. All further steps are processed automatically. All data processing, control of the measurement process and calculating of the result is done by an external PC with Windows®-based software. Thermogravimetric analysis of moisture, volatile and ash content requires about 4 hours.
