Dielectrophoretic Gold Particle Separation

We present a novel process for gold particle separation from aqueous setup with a high separation efficiency and without any environmental risk. Dielectrophoresis (DEP), as the main mechanism of this separation process, is applied for the first time to separate gold even continuously from a raw mineral mixture. Electrothermal and high-pass-filter effects, occurring in DEP with water as liquid phase, were investigated and considered during the design of the separation process. The experimental results demonstrate that even ultra thin gold particles can be separated from a raw mineral mixture with an efficiency of up to 88% at an electric field of 32 kV/m and 200 kHz in continuous operation with specific fluid flow of about 400 m(3)/(m h).