Electrolysis of Low-temperature Suspensions: An Update

Among different “novel” technologies for eco–friendly aluminium production with zero greenhouse gas emissions, the electrolysis of alumina suspension (or slurry) based on halide melts deserves more attention than it got recently. The original idea of the slurry was first proposed by Theodor R. Beck and has been modified and developed basically by Petr V. Polyakov. This paper presents a comprehensive analysis of the current status of this technology, future opportunities, and the new experimental results, which have not been published yet. This overview covers the properties of high-temperature suspensions, including sedimentation behaviour and apparent electrical conductivity; anodic process on oxygen-evolving electrodes, including the polarization characteristics and the bubble behaviour at vertical anodes; cathodic process on wettable substrates; primary electrolysis results; and the general considerations touching upon the possible cell designs and the thermal balance. The future scope of the technology and possible applications are discussed.