Review—Preparation of Hafnium Metal by Electrolysis

Hafnium, owing to its excellent mechanical characteristics, corrosion resistance, high temperature resistance, and remarkable nuclear attributes, is widely used in a variety of fields, including aerospace engineering, nuclear technology, and metallurgy. Nonetheless, the burgeoning nuclear industry has led to an increasing demand for hafnium of elevated purity, and the conventional thermal reduction method for producing hafnium metal is no longer sufficient to meet the market requirements. This review summarizes recent progresses on the extraction and purification technology of hafnium metal, with a specific focus on the electrolysis process, as a prospective alternative to the conventional Kroll process. The electrolysis process can be divided into two categories: molten salt electrolysis and electro-deoxidation. The principles, flow, current status, and obstacles of industrial application of these electrolysis processes are discussed in detail. The review conclusively offers recommendations and maps out the prospects for future research exploration on hafnium metal.