Specific information on the method:
The CM100B mill has a 100 liter milling drum set up to study the synthesis of hydrogen storage materials via high energy milling during scale-up.
- The high energy milling is achieved through an extremely high rotation speed from the rotor which sets the balls in motion. In this way, reductions in milling time from 8 to 1/2 h are achievable, depending on the milled material.
- A further reduction in processing time is achieved through the increased size of the milling batches (20 kg), since less batches are needed for the same amount of material, and through the use of an autobatch feature which allows the automated charge and discharge of the milling drum.
Specific information on the equipment/instrumentation:
The mill is equipped with specific sensors in order to be able to study the synthesis process: temperature and pressure sensors record the changes inside of the milling drum, especially when chemical reactions take place. A particle size analyzer is also attached to follow the particle size of the material during milling. Last, but not least, the atmosphere inside the drum is watched via oxygen and moisture sensors to avoid unwanted reactions and as a safety feature in case of leaks.
Samples/limitations:
The limit milling conditions are 70 °C and 1.5 bar. Milling can be done in the autobatch mode only with dry samples. The samples should not be chemically aggressive against the rubber seals of the connections. Otherwise theree are no limitations of the samples to be milled under protective atmosphere.n
Examples of typical analytical questions:
A sample of up to 20 kg in size of a hydrogen storage material such as sodium alanate can be mixed and milled with its catalyst using this equipment. It is equally suitable for boron based materials, room temperature hydrides or amide/imide compounds.