The invention discloses a wet treatment method for ferronickel and application thereof; and the treatment method comprises the following steps of: in a high-pressure
oxygen environment, mixing crushed ferronickel, sulphuric acid and a
corrosion aid, performing acid leaching reaction, performing
solid-liquid separation on
slurry after acid leaching, adding an
oxidizing agent into the obtained filtrate, performing heating, removing the
corrosion aid, adding a precipitator into the filtrate, controlling the pH value of the filtrate, and performing
solid-liquid separation to obtain
ferric hydroxide precipitate and
nickel-containing filtrate; and performing extraction and back extraction on the
nickel-containing filtrate to prepare battery-grade
nickel sulphate. According to the invention, the ferronickel is subjected to oxidation
acid dissolution in cooperation with the
corrosion aid under the high-pressure
oxygen and acidic conditions; the ferronickel is extremely prone to oxidation in the high-pressure
oxygen environment; and a strong oxidant is added into the filtrate subsequently, so that
ferrous ions in the filtrate are completely converted into
ferric ions, the corrosion aid can be oxidized to generate
pollution-free
carbon dioxide and water, and the influence of the corrosion aid on the subsequent extraction process is avoided.