SYSTEM AND METHOD FOR PRODUCING 3.5-VALENCE HIGH-PURITY VANADIUM ELECTROLYTE

Disclosed herein are a system and method for producing a 3.5-valence high-purity vanadium electrolyte, comprising hydrolyzing high-purity vanadium oxytrichloride into vanadium pentoxide in a fluidized bed (2) by means of gas phase hydrolysis, and in a reduction fluidized bed (5), reducing vanadium pentoxide into a low-valence vanadium oxide having an average vanadium valence of 3.5 through precise control, and adding water and a sulfuric acid solution under microwave field applied externally for dissolution at a low temperature, to obtain a 3.5-valence high-purity vanadium electrolyte which can be directly used in a new all-vanadium redox flow battery stack. The preparation of vanadium pentoxide by means of gas-phase hydrolysis in the fluidized bed (2) is of short process and high efficiency. By providing an internal member within the reduction fluidized bed (5), the precise regulation of the valence state of the reduction product is achieved, and the special chemical effect of the microwave field is used to promote dissolution of the vanadium oxide and activate the vanadium ions, and the dissolution and preparation of the electrolyte is performed in a low temperature range, thereby greatly improving the activity of the electrolyte. The present method has the advantages of short process, high efficiency and good cleanliness, and stable product quality, etc. and is applicable to large-scale industrial production, with good economic and social benefits.