Perlite-obsidian separation using electric mothods

Among the various industrial minerals occurring in Sardinia (Italy), the perlite minerals are not to be overlooked. Mining of perlite deposits is however hampered by the presence of obsidian and lesser amounts of mica as well as other accompanying minerals. In order to obtain a perlite material as free as possible of the above contaminants, a systematic investigation has been carried out for exploring the potential applicability of different beneficiating methods. This paper describes the basic studies conducted on the perlite and obsidian for determining the surface electric charge acquired on contact with various materials. The results of separation tests performed in a climate chamber using electric separators that rely on ionic charging are discussed for varying feed size and ambient conditions. The findings demonstrate the potential of electric techniques for separating the perlite from obsidian.