Canciani Chiara, Sarvothaman Varaha P, Viciconte Gianmaria, Colleoni Elia, Guida Paolo, Roberts William L
Clean Energy Research Platform (CERP), Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Clean Energy Research Platform (CERP), Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Ultrason Sonochem. 2025 Sep;120:107501. doi: 10.1016/j.ultsonch.2025.107501. Epub 2025 Aug 6.
Dissolutions are entailed in a wide variety of industrial processes, and acoustic cavitation is being researched as a powerful tool to intensify these processes. In particular, when applied to the leaching of battery cathode material in hydrometallurgical recycling, it paves the way to the utilization of organic acids in place of mineral acids, lowering the hazardousness and cost of recycling. In this framework, mapping the cavitation activity and understanding the relation between acoustic cavitation and the action of the acid is fundamental for the design and control of the intensified process. This work used the leaching of NMC (lithium nickel manganese cobalt oxide) cathode particles as a model system. Leaching reduces the average particles size from 10 μm to 1.5 μm, reflecting the 85 % reduction in residual mass over 10 min. The cavitation activity was measured by means of a hydrophone in different conditions, to isolate and assess the effect of acoustic cavitation and leachant separately. The acoustic spectra enabled the quantification of the cavitation activity. In particular, the cavitation intensity decreased by 3 orders of magnitude in the leaching system, in a specific time window of the process, to rise again towards the end of the experimental time. This effect was not observed in non-leaching systems, suggesting an interaction between the acid and the particles is the cause of such phenomenon. The characterization of the solid through scanning electron microscopy (SEM) and surface area quantification by gas adsorption helped to narrow down on the cause of such attenuation, i.e. the cushioning effect related to oxygen release during the reaction. Along with this, the acoustic spectra coupled with the characterization of the solid particles highlighted a dependance of the cavitation activity on the total surface area of the solid. These findings enable deeper understanding of the effect of the presence of particles in a cavitating system, leading to better control and design of leaching reactors.
溶解过程涉及到各种各样的工业流程，而声空化作为一种强化这些流程的有力工具正受到研究。特别是，当应用于湿法冶金回收中电池阴极材料的浸出时，它为使用有机酸替代无机酸铺平了道路，降低了回收的危险性和成本。在此框架下，绘制空化活性图谱并理解声空化与酸的作用之间的关系对于强化过程的设计和控制至关重要。这项工作以NMC（锂镍锰钴氧化物）阴极颗粒的浸出作为模型系统。浸出使平均颗粒尺寸从10μm减小到1.5μm，这反映出在10分钟内残余质量减少了85%。通过水听器在不同条件下测量空化活性，以分别分离和评估声空化和浸出剂的影响。声谱能够对空化活性进行量化。特别是，在浸出系统中，在该过程的特定时间窗口内，空化强度降低了3个数量级，在实验时间接近尾声时又再次上升。在非浸出系统中未观察到这种效应，这表明酸与颗粒之间的相互作用是导致这种现象的原因。通过扫描电子显微镜（SEM）对固体进行表征以及通过气体吸附对表面积进行量化，有助于缩小这种衰减原因的范围，即与反应过程中氧气释放相关的缓冲效应。与此同时，声谱与固体颗粒的表征相结合，突出了空化活性对固体总表面积的依赖性。这些发现有助于更深入地理解空化系统中颗粒存在的影响，从而更好地控制和设计浸出反应器。
