The 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.

中文翻译：

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用钼废催化剂合成钼酸铁及其电化学性能评估

当前的手稿涉及通过焙烧，浸出和水热沉淀从钼废催化剂合成钼酸铁纳米材料。优化了焙烧过程中废催化剂与碳酸钠的比例，浸出时间，氨在浸出液中的浓度以优化钼的实验参数。在80°C的条件下进行5 h浸出的条件下，从5 M氨水中的焙烧催化剂中提取出最多93％的Mo。然后从浸出液中，通过水热法在硫酸亚铁铵，硝酸铁和硫酸铁等不同的铁前体中合成钼酸铁Fe ₂（MoO ₄）₃。然后，针对Fe ₂的合成优化了不同的合成参数（MoO ₄）_3.根据最佳条件，提出了暂定流程图，并讨论了影响产品形态的因素。Fe ₂（MoO ₄）₃显示出通过循环伏安法研究证实的电容行为，并且估计的最大比电容为33 F g ^-1。