Molten salt corrosion of candidate materials in LiCl–KCl eutectic for pyrochemical reprocessing applications: a review

Abstract High temperature molten salt corrosion is of utmost importance for selecting and qualifying structural materials for critical applications. Pyrochemical reprocessing of spent metallic fuels of the future fast breeder reactors in India is widely considered. One of the main processes of pyrochemical reprocessing is electrorefining. Electrorefining is generally conducted in LiCl–KCl molten salt at 500–600 °C under an inert atmosphere. Research groups worldwide are involved in developing corrosion resistant materials and investigating the corrosion behaviour of various structural materials for LiCl–KCl applications under different environments. A wide variety of materials, including metals, alloys, intermetallics, single crystals, glass and ceramics, have been investigated in molten LiCl–KCl salt. This review focuses mainly on the corrosion assessment of materials for LiCl–KCl application; a complete literature review with emphasis on the corrosion issues of materials is provided. This paper reviews the corrosion issues of metals and alloys in molten salts and the selection criteria of corrosion-resistant materials for molten salts. Understanding the molten salt corrosion mechanisms and future research scope are also discussed.