How to Select your prepASH™ Crucible
Depending on your application, you may require a certain size or shape of crucible for optimal results – and with Precisa’s prepASH™, there is a wide variety of crucibles to suit your research needs.
Key Points:
- A wide range of samples can be analysed with the highest accuracy, reliability, and precision due to the variety of crucibles offered.
- The crucibles offered allow the prepASH to adapt to your needs: with large crucibles for hard to ash samples, wide crucibles for sulfuric acid applications and smaller crucibles to accommodate more samples in a single run.
What is the Precisa prepASH?
The series 340 prepASH is a thermogravimetric analyzer (TGA) that automatically measures moisture, ash, and loss on ignition at a reduced workload and cost compared to conventional methods of thermogravimetric analysis. The TGA works completely autonomously once loaded and started, with analysis operating at temperatures up to 1000oC.
How many samples can the prepASH analyse?
The prepASH comes in three different sizes, which correlates to the size of the sample plate;
- prepASH 229: can analyse 19 or 29 samples using 35ml crucibles or 26ml crucibles. Alternatively, 12 samples can be analysed using 40ml or 50ml crucibles.
- prepASH 219: can analyse 19 samples using 35ml or 26ml crucibles. Alternatively, 12 samples can be analysed using 40ml or 50ml crucibles.
- prepASH 212: can analyse 12 samples using 40ml or 50ml crucibles.
What are prepASH crucibles used for?
The prepASH uses porcelain glazed crucibles to hold samples during analysis. These crucibles are placed onto a sample plate holder, which rotates the crucibles to ensure homogeneous temperature distribution and continual weighing of each sample. All Precisa crucibles are compatible with the built in analytical balance, enabling direct weighing-in and continuous weighing throughout the run.
What different sizes of crucibles are available?
There are a variety of shapes and sizes of crucibles, which you can utilise depending on the prepASH model and sample plate holder.
- 340-8032: This crucible is 26ml and can be used in the 19 or 29 sample plate holders. These crucibles are used for volatile analysis such as coal and coke – the crucible is a special shape to accommodate the lid
- 340-8037: This crucible is 35ml and can be used in the 19 or 29-sample plate holders. These crucibles are used for any application except coal, and they are safe for applications with acid.
- 340-8034: This crucible is 40ml and fits on the 12 sample plate holder (can be used for prepASH 229 and 219 also if 12 sample holder is purchased). These crucibles are safe for applications with acid.
- 340-8038: This crucible is 50ml and fits on the 12 sample plate holder (can be used for prepASH 229 and 219 also if 12 sample holder is purchased).
- 340-8035: This is a crucible adaptor, used with the 340-8034 and 340-8038 crucibles.
Why are there different types of crucibles available?
We offer a variety of crucibles to accommodate a wide range of samples. This allows for a resolutely versatile product, which can adapt to your needs to ensure accurate and reliable results for all sample types.
What crucibles are suitable for my application?
Large crucibles (50ml): Allows for the analysis of a larger sample amount. A larger sample amount may be required if your sample has a very low ash content or if you have an inhomogeneous sample. For example, oil and fat have very low ash content (can be as low as 0%), and a bigger crucible allows for a larger sample mass to be analysed.
High crucibles: Allows for the analysis of foaming samples, which can occur during sulphated ash analysis. For example, sulfuric acid if often used for samples that contain a high organic content – as this helps to oxidise the organic matter to facilitate the combustion process.
Crucibles with lid: Allows for the analysis of volatile matter in coal and coke samples.
Small crucibles (35ml): Allows for the analysis of more samples simultaneously. For example, many customers use this crucible size for the analysis of food such as flour and cereals. This size of crucible is also ideal for polymer analysis, which includes plastic and rubbers.
Can platinum crucibles be used?
Precisa do not make any platinum crucibles – but it is still possible to use this type of crucible in the prepASH. As long as the platinum crucibles can fit into the adaptors, then they can be used.
Further reading:
Thermogravimetric Analysis with prepASH