The invention relates to a venturi tube-based
iron oxide preparation device, which comprises a reaction kettle, a venturi tube, a
circulating pump, an
oxygen storage device, a
gas mixing cylinder and the like, a
solid-liquid mixed reactant is stored in the reaction kettle, the reaction kettle is provided with a circulating gas outlet, a circulating liquid outlet and a circulating liquid inlet, and the
gas mixing cylinder mixes air and
oxygen and then inputs the mixture into the venturi tube; a liquid reactant enters the Venturi tube through the
circulating pump, gas and liquid are fully mixed in the Venturi tube and then return to the reaction kettle, and a stainless steel heating tube is arranged in the reaction kettle to provide a heating environment. A filtering tank, a fine hole partition plate, a
liquid level sensor, a temperature sensor, an
oxygen content sensor and the like are further arranged. The device achieves the technical effects that oxygen in the air fully reacts with
solid-liquid mixed reactants,
iron oxide yellow,
iron oxide red and
iron oxide black can be produced according to different proportions, the universality of the device is improved, meanwhile, the efficiency of the
circulating pump is improved, the service life of the circulating pump is prolonged, it is guaranteed that the reaction is conducted at the appropriate temperature and under the appropriate
oxygen content, and product discharging is facilitated.