The Pulverisette 2 grinds the sample through friction, which means that there is no thermal load on the material unlike a ball mill
In many laboratories, samples are still ground using a hand held pestle and mortar.
Despite the fact that a better method has been available for many years: namely the mortar grinder Pulverisette 2.
With this mill, the pestle is held against the wall of a rotating mortar bowl with adjustable, reproducible spring pressure.
The grinding time is set with a digital timer.
A scraper on the inside wall of the mortar bowl ensures that the sample is always re-directed towards the fixed pestle.
The result is considerably more homogeneous and reproducible than grinding with a hand mortar also the mill is very easy to clean.
The mortar bowl and pestle can be removed without tools in just two easy motions for quick cleaning.
Thanks to the gentle grinding, one of the main applications for this mill is in the pharmaceutical industry for galenics to confirm the quantity of active ingredients in drugs (tablets and dragees).
The tablets need to be ground up after manufacturing in order to verify the active ingredient content as part of quality assurance.
None of the active ingredients may be lost during the preparation.
10-20 tablets are ground in a grinding set of agate or porcelain.
After 1-5 minutes, a fine (<100um), homogeneous powder is produced which can be used for the analysis.
The Pulverisette 2 is very well suited to many other applications.
For example, with mortar bowls made of stainless steel which have been available for some time, grinding at low temperature in liquid nitrogen is possible.
The following images show the grinding of tomato pieces.
These are first frozen in liquid nitrogen to make them brittle.
Then they are placed in the mortar bowl and liquid nitrogen added.
After a few minutes, the result is a fine, homogeneous powder.
In addition to comminution, other applications for the Pulverisette 2 include the mixing of solids or the mixing of solids with liquids.
For instance, the mortar grinder is used for mixing pure liquid mercury with a fine metal powder.
Another application is the mixing of a metallic powder with a highviscosity synthetic resin.
Using a grinding set of hardened steel and a grinding time of 30 minutes, it is possible to homogeneously mix solids to over 80 percent by weight through gradual addition of the powder.
The following images show the doping of ceramic powders with very small quantities of substances dissolved in a liquid.
During operation of the mill, roughly 1ml of coloured liquid was slowly dripped into the ceramic powder.
After about five minutes, a homogeneous, visually uniform powder is obtained.
The examples described above demonstrate just some of the diverse uses for the Mortar Grinder Pulverisette 2.
Of course, the full range of applications is more comprehensive.
This capability makes it an essential tool for sample preparation which no laboratory can afford to be without.
