vanadium iii sulfate is an inorganic compound with the formula V 2 (SO 4 ) 3. It is a pale yellow solid that is stable to air but slowly dissolves in water to produce the green aquo complex [V(H2O)6]3+.
It is a reducing agent and is useful for making organic light emitting diodes. It is also used as a catalyst in the production of ethylene propylene diene monomer rubber and polyethylene.
In addition, it is an excellent electrolyte for use as a negative electrode in a redox flow battery that uses vanadium ions to store surplus power during the night and use it during the day. However, it is difficult to completely remove the generated hydrogen chloride in the reaction and it has a high production cost.
As a result, there is a need for a solution that can efficiently remove the generated hydrogen chloride. One method is to reduce the excess sulfur by a reducing agent such as sulfur dioxide in an aqueous sulfuric acid solution.
Then, the solution is cooled to 30 deg C or lower and filtered through an acid-resistant filter. The filtrate mainly contains sulfuric acid and can be reused for the reaction with vanadium (III) oxide.
In order to produce the aqueous solution, vanadium (III) oxide is heated in an aqueous sulfuric acid to a temperature of 90 deg C or higher. Then, the resulting solid vanadium sulfate is recovered from the solution. Afterwards, the aqueous solution is diluted to obtain the desired [V (H 2 O) 6] 3+ and SO 4 2+ concentration.