The Planetary Ball Mill PM 300 is a powerful and ergonomic benchtop model with two grinding stations for grinding jar volumes up to 500 ml. This setup allows for processing up to 2 x 220 ml sample material per batch. Thanks to the high maximum speed of 800 rpm, extremely high centrifugal forces result in very high pulverization energy and consequently in short processing times.
The PM 300 is ideally suited for virtually all industries where the quality control process places the highest demands on purity, speed, fineness and reproducibility. Thanks to its enormous energy input of up to 64.4 times the acceleration of gravity, this mill is the perfect choice for tasks in research like mechanochemistry (co-crystal screening, mechanosynthesis, mechanical alloying and mechano-catalysis), or for ultrafine colloidal grinding on a nanometer scale.
Benefit from particularly ergonomic handling while achieving the same finenesses down to the nanometer range.
Operation of the RETSCH planetary ball mills is particularly safe. They feature a robust Safety Slider which ensures that the mill can only be started after the grinding jar has been securely fixed with a clamping device. The self-acting lock ensures that the jar is seated correctly and securely. This proven solid mechanical system is less failure-prone than electronic solutions - the user has full access to the sample at any time. When the electronic system fails, it is not possible to unlock the jars, for example. A unique safety feature of the PM 300 is an acoustic signal and notification in the display when the clamping unit has been fixed with the required force of 25 Nm. RETSCH offers a convenient clamping aid to facilitate the process. This is particularly helpful when the machine is operated in the upper speed range between 600 and 800 rpm.
Wet grinding is used to obtain particle sizes below 5 µm, as small particles tend to get charged on their surfaces and agglomerate, which makes further grinding in dry mode difficult. By adding a liquid or dispersant the particles can be kept separated.
To produce very fine particles of 100 nm or less (nano-scale grinding) by wet grinding, friction rather than impact is required. This is achieved by using a large number of small grinding balls which have a large surface and many friction points. The ideal filling level of the jar should consist of 60 % small grinding balls.
For more details on jar filling, wet grinding and sample recovery watch the video.
The video shows wet grinding in the Planetary Ball Mill PM 100.
The graphic shows the result of pulverizing titanium dioxide (TiO2) at 650 rpm and 800 rpm in the PM 300 and the net processing time. With the higher energy input at 800 rpm, the particle size decreases faster. However, the increased warming effects at 800 rpm should also be considered, as they might make longer breaks necessary.
Net processing time of titanium dioxide with 0.1 mm grinding balls in sodium phosphate solution
