Process for extracting iron from an aqueous acid solution

The invention relates to an iron extraction process from an aqueous acid solution containing ferrous ions. The acidic feed solution is first passed to a fluidized bed reactor for the oxidation of the ferrous ions preferably by microbes (Leptospirillum ferriphilum) to give ferric ions, followed by introducing the solution obtained to a concentrator for the precipitation of a compound containing ferric ions from the solution to give solid matter. The final product, i.e. solid matter containing ferric ions, is collected. In the process, the solution to be treated is passed through the fluidized bed at a flow rate sufficient for effective fluidization and mixing in the fluidized bed. Further, an apparatus for performing the iron extraction process is claimed. The carrier for the microbes may be activated carbon.