A new process for leaching metal values from ocean polymetallic nodules

A new process for leaching metal values from ocean polymetallic nodules is introduced in this paper. The novel process consists of a few parts as follows: The liquid-phase oxidation of the ocean polymetallic nodules in the presence of oxygen by utilizing molten potassium hydroxide as medium to produce potassium manganate; the production of potassium permanganate from disproportionation of potassium manganate; the production of pure manganese dioxide and oxygen from thermal decomposition of potassium manganate; the clarification and recycling of potassium hydroxide; and the recovery and refining of the other enriched metal values by reduction ammonia leaching. The new process has the characters of less pollution and low energy consumption.