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This review focuses on recent developments in molten-salt electrolytic metallurgical processes with respect to 1) high-efficiency metallurgical technologies via electrolytic reduction of solid oxides in molten chlorides and 2) zero-carbon-footprint electrochemical splitting metallurgical technologies. Initiating with an introduction on dynamic solid/solid/liquid three-phrase interlines electrochemistry for electrochemical reduction of solid cathode, the former aspect is discussed in terms of facilitating mass transfer throughout solid cathode, one-step production of functional alloy powders with the assistance of under-potential electroreduction of active metals and near-net-shape production of metal/alloy components. Whilst the latter is summarized by introducing some zero-carbon molten-salt electrolytic technologies including electro-splitting of solid sulfides in molten chlorides, electrometallurgical technology in molten carbonates and molten oxide electrolysis. With an attempt to demonstrate the proof-of-concept, the merits of molten-salt electrolytic technologies on environmental viability, energy-profitability and resource-utilization are also justified and highlighted, which, as hope, could form a basis for developing novel electrolytic processes for clean, energy-efficient and affordable metallurgy of materials.

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molten salts, electrochemistry, metallurgy, less carbon footprint

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