Environmentally Protecting Reactive Milling

摘要

Horizontal high energy ball-mills are known from academic as well as industrial applications in mechanical alloying (MA), high energy milling (HEM) and reactive milling (RM). They supply the highest relative velocity of grinding media, which leads to an intensive grinding effect, short process times and a lower contamination of the processed powders by the milling tools due to a process that is based more on the collision of the grinding media than on their shear and friction interaction. Since the grinding media are accelerated by a horizontally arranged rotor inside the grinding vessel, these devices have the additional advantage of not moving unnecessarily any large masses like e.g. the entire chamber/mill in the cases of vibration ball-mills. The systems are presently available at 0.5 to 400 L grinding chamber capacity and larger volumes seem to be possible. Various existing applications for the environment include MA of different metals and/or ceramics, decontamination of dangerous, residues by using the tribochemistry of milled sand (SiO_2) and waste-free organic chemical solid-state syntheses with 100% yield. In particular these procedures are economically and ecologically favorable as in most cases they can be operated semi-automatically if they are combined with a continuous or semi-continuous (auto-batch) powder separation system. We report here on some applications of HEM/RM.