Device and method for preparing ferric oxide yellow

The invention provides a device and a method for preparing ferric oxide yellow. The device comprises 1, a first sample introduction device, 2, a second sample introduction device, 3, a gas inlet device, 4, a reactor of which an inlet is connected to an outlet of the first sample introduction device, an outlet of the second sample introduction device and an outlet of the gas inlet device, 5, a heating device which is used for heating the reactor, 6, a pH adjustment device which is used for adjusting a pH value of the reaction solution in the reactor, and 6, a bipolar-membrane electrodialysis device of which an alkaline chamber outlet is connected to an inlet of the second sample introduction device. The device for preparing the ferric oxide yellow utilizes alkaline liquor produced by the bipolar-membrane electrodialysis device as an antalkali, and adjusts a pH value of the reaction solution in ferric oxide yellow preparation. The method does not utilize an antalkali having a high price to prepare the ferric oxide yellow so that a ferric oxide yellow production cost is reduced. The device and the method realize effective treatment on an inorganic salt waste liquid produced by ferric oxide yellow preparation and realize resource recovery and utilization.