Abstract The main aim of this study was to develop a new process for nickel recovery from low-grade nickel laterite and to investigate its usability as an alternative and low-cost process. The process consists of two main steps: first, the treatment of laterite by reagent-assisted mechanochemical conversion (R-MC); second, recovery of nickel from treated laterite with (U-AL) and without (AL) ultrasound-assisted leaching. R-MC processes were carried out using Na2SO4 and Na2CO3 as reagents. The effect of reagents was investigated by evaluating the leaching selectivity of nickel over iron. Response Surface Methodology (RSM) was used to improve the performance of the processes. Nickel recoveries were achieved over 90% for both processes. The dissolution of nickel and iron from R-MC treated laterite was controlled by a combination of chemical and diffusion reactions for both leaching processes. Moreover, it was also observed for both leaching processes that dissolution activation energies of nickel and iron from R-MC treated laterite, were markedly reduced compared to raw laterite. According to results, the synergistic effect of both ultrasonic power and mechanochemistry on the leaching process contributes positively to the completion of the leaching in a shorter time by accelerating the reaction and facilitating the mass transfer.

中文翻译：

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带和不带超声效应浸出工艺结合试剂辅助机械化学工艺从红土矿中回收镍的性能评价：工艺优化和动力学评价

摘要 本研究的主要目的是开发一种从低品位红土镍中回收镍的新工艺，并研究其作为替代和低成本工艺的可用性。该过程包括两个主要步骤：首先，通过试剂辅助机械化学转化（R-MC）处理红土；其次，从使用（U-AL）和不使用（AL）超声辅助浸出处理的红土中回收镍。R-MC 过程使用 Na2SO4 和 Na2CO3 作为试剂进行。通过评估镍对铁的浸出选择性来研究试剂的影响。响应面方法 (RSM) 用于改进过程的性能。两种工艺的镍回收率均超过 90%。镍和铁从 R-MC 处理的红土中的溶解是由两种浸出过程的化学和扩散反应的组合控制的。此外，还观察到对于两种浸出过程，与未加工的红土相比，R-MC 处理的红土中镍和铁的溶解活化能显着降低。结果表明，超声功率和机械化学对浸出过程的协同作用通过加速反应和促进传质对在更短的时间内完成浸出做出积极贡献。