LiCoO2在酸性焙烧环境中元素赋存形式的演变规律及分布特征研究

Occurrence Evolution and Distribution of Elements in the Sulfating Roasting Process of LiCoO2

摘要:

系统地了解钴酸锂(LiCoO2)在不同介质环境中的物理化学性质有助于从理论上指导该物质的合成工艺设计以及报废LiCoO2再利用的工艺设计。本文将LiCoO2与NaHSO4稨2O、LiCoO2与Na2S2O7分别按摩尔比1:3、1:1.5的比例混合后进行酸性焙烧，采用TG-DSC-MS、XRD、SEM、EDS研究了焙烧过程中元素赋存形式的演变规律以及元素分布特征。研究结果表明：LiCoO2与NaHSO4稨2O、Na2S2O7的混合物在焙烧过程中发生了明显的化学反应。焙烧产物中Na元素的赋存形式有Na2SO4、LiNaSO4和Na6Co(SO4)4，Li元素的赋存形式为LiNaSO4，Co元素的赋存形式为Na6Co(SO4)4。焙烧产物致密，形状不规则，Co元素在焙烧产物中分布均匀。

Abstract:

It is of benefit for synthesizing and reusing process design of LiCoO2 to understand systemically the physicochemical property of LiCoO2 in the different conditions. In this paper, the mixture samples of LiCoO2 and NaHSO4稨2O with the molar ratio of 1:3, LiCoO2 and Na2S2O7 with the molar ratio of 1:1.5 were roasted. Occurrence evolution and distribution of elements in the sulfating roasting process of LiCoO2 have been studied by TG-DSC-MS, XRD, SEM and EDS. The results showed that reactions have been taken place in roasting. Occurrence of Na element is Na2SO4, LiNaSO4 and Na6Co(SO4)4. Occurrence of Li, Co element is LiNaSO4 and Na6Co(SO4)4 respectively in roasting products. The roasting products have a dense tissue and irregular shape. Distribution of Co element is homogeneous in the roasting products.