Synthesis of iron molybdate from molybdenum spent catalyst and evaluation of its electrochemical properties

AbstractThe current manuscript deals with synthesis of iron molybdate nano‐material from molybdenum spent catalyst via roasting, leaching, and hydrothermal precipitation. Experimental parameters like ratio of spent catalyst to sodium carbonate during roasting, time duration of leaching, and concentration of ammonia to obtain molybdenum into leach solution were optimized. A maximum 93% Mo was extracted from roasted catalyst in 5 M ammonia at 80°C for 5 h leaching condition. Then from the leach liquor, iron molybdate Fe2(MoO4)3 was synthesized by hydrothermal method in different iron precursors such as ferrous ammonium sulphate, ferric nitrate, and ferric sulphate. Then, different synthesis parameters were optimized for the synthesis of Fe2(MoO4)3. Based on the optimal conditions, a tentative flow‐sheet has been proposed and factors influencing the morphology of the product have been discussed. This Fe2(MoO4)3 showed capacitive behavior confirmed through cyclic voltammetry study and a maximum specific capacitance of 33 F g−1 was estimated.