引用本文:
赵丽丽, 王榕树. 锂离子交换剂制备及交换反应动力学[J]. 物理化学学报,
2003, 19(10): 933-937.
doi:
10.3866/PKU.WHXB20031010
Citation: Zhao Li-Li, Wang Rong-Shu. Preparation of MnO2(Li) and Its Ion Exchange Kinetics[J]. Acta Physico-Chimica Sinica, 2003, 19(10): 933-937. doi: 10.3866/PKU.WHXB20031010

Citation: Zhao Li-Li, Wang Rong-Shu. Preparation of MnO2(Li) and Its Ion Exchange Kinetics[J]. Acta Physico-Chimica Sinica, 2003, 19(10): 933-937. doi: 10.3866/PKU.WHXB20031010

锂离子交换剂制备及交换反应动力学
摘要:
通过XRD分析、Li+抽出率βLi及Mn2+溶出率γMn的计算,考察了不同焙烧温度及抽锂剂对前驱体锂锰氧化物LiMn2O4结构及稳定性的影响.结果表明, 750 ℃下焙烧2 h,并使用过硫酸铵(NH4)2S2O8作抽锂剂,制备的Li+交换剂MnO2(Li)对Li+的交换容量αLi较大.另外,通过Li+在固液两相间分配系数的测定及交换反应动力学实验,对离子交换反应机理进行了研究,并建立了有限浴条件下MnO2(Li)离子交换反应动力学模型.结果表明,该离子交换过程近似符合颗粒扩散控制;交换反应主要发生在交换剂颗粒外层;提出的动力学模型与实验结果符合较好.
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关键词:
- 抽锂剂;锂锰氧化物;锂离子交换剂;动力学
English
Preparation of MnO2(Li) and Its Ion Exchange Kinetics
Abstract:
The effects of calcination temperatures and extractants on the structure and chemical stability of LiMn2O4 were examined by XRD, βLi (degree of Li+ extraction) and γMn(degree of Mn2+ dissolution) analyses, the results show that MnO2(Li) prepared at 750 ℃ for 2 h has larger exchange capacities using (NH4)2S2O8 as extractant. In addition, the mechanism of ion exchange reaction was studied by distribution coefficient measurement and kinetic experiment, and the mathematical model for ion exchange reaction kinetics in a finite solution has been established. The results indicate that this ion exchange process is controlled by particle diffusion; ion exchange reaction mainly occurs in the outer layer of MnO2(Li). The experimental results are in od agreement with the calculated values.

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