Research progress in potassium ferrate synthesis methods: Synthesis mechanism, process optimization, and efficiency evaluation

Potassium ferrate is an eco-friendly and efficient water treatment reagent which integrates multifunction including oxidation, disinfection, flocculation, and adsorption. However, the complex synthesis process, high synthesis cost, and relatively low synthesis efficiency of potassium ferrate have limited its large-scale engineering application. Recently, potassium ferrate synthesis techniques represented by dry oxidation method (i.e., fusion method), wet oxidation method (i.e., hypochlorite oxidation method), and electrolysis method have been developed. A growing number of research has focused on optimizing and iterating the potassium ferrate synthesis process, aiming to simplify the process, reduce costs, and improve synthesis efficiency. This review provides a comprehensive overview of three major types of potassium ferrate synthesis methods, deeply analyzing the synthesis principles, conditions, and factors influencing the process efficiency of each method. It details the optimization process of various methods and comparatively analyzes the advantages and disadvantages of different synthesis techniques. Through a systematic review and summary of the current research progress of the synthesis of potassium ferrate, this review aims to provide important reference for the development of efficient, economical, and environmentally friendly potassium ferrate synthesis processes, laying a solid foundation for the engineering application of potassium ferrate in water treatment technology.