中文摘要：

研究了一种以单水氢氧化锂为原料制备高纯度氧化锂的新型真空热分解工艺。考察了坩埚材质对真空加热单水氢氧化锂制备氧化锂的影响及其反应机制,并探索了制备氧化锂的最佳条件。实验结果表明,坩埚材质对真空加热单水氢氧化锂的产物有显著影响,在锂化刚玉坩埚中能够获得高纯度的氧化锂;在石墨坩埚和镍坩埚中分别得到中间产物碳酸锂和无水氢氧化锂,延长950℃保温时间能得到纯度较低的氧化锂;在铁坩埚中不能得到氧化锂。提高温度及延长高温保温时间都能一定程度上提高锂化刚玉坩埚中产物氧化锂的纯度。采用新的真空热分解工艺在锂化刚玉坩埚中得到纯度高于98.9%的氧化锂。与传统氧化锂的制备方法相比,此新型真空热分解工艺采用的原料易取好保存,简化了氧化锂的制备流程,降低了生产成本,且操作简便。这对工业上低成本大量生产氧化锂具有重要意义。

英文摘要：

High-purity lithium oxide was prepared by vacuum pyrolytic process with the starting material of lithium hydroxide mono- hydrate. The effect of crucible materials on the products of vacuum pyrolysis reaction was studied, as well as the mechanism of the vacuum pyrolysis reaction for lithium oxide preparation in different crucibles. The optimal conditions for synthesis of lithium oxide were also investigated. The results suggested that crucible material had a significant influence on the vacuum pyrolytic process of lithium hydroxide monohydrate, and high-purity lithium oxide was obtained in lithium modified corundum crucible. Lithium carbonate and lithium hydroxide were obtained firstly in the graphite crucible and the nickel crucible, respectively, and low-purity lithium oxide were obtained when the holding time at 950 ℃ was prolonged. Lithium oxide could not be obtained in iron crucible. In lithium modified corundum crucible, higher pyrolytic temperature and longer holding time at pyrolytic temperature would benefit the purity of lithium oxide. Lithium oxide with a purity of higher than 98.9% could be obtained in lithium modified corundum crucible by this new vacuum pyrolytic process. Compared with the traditional methods for the preparation of lithium oxide, this new vacuum pyrolytic process had potential for lowering the production cost because of cheap raw material, simple preparation process and friendly working condition for operators. This new vacuum pyrolytic process was promising for mass production of lithium oxide at low cost in industrial production.