关键词: 高纯碳酸锂, 化学分步沉淀, 粗碳酸锂

Abstract: According to the characteristics of high Li-Mg ratio of the Zabuye Lakes，coarse lithium carbonate separated from the brine was used as the raw material and an economical and practical chemical precipitation method was introduced to eliminate the impurity through fractional alkalization，and then the carbonated precipitation had been applied to get high purity lithium carbonate.The influence of different water systems，process of sedimentation，and carbonation precipitant on the purity of lithium carbonate had also been investigated.High purity lithium carbonate was characterized by plasma emission spectrum（ICP），infrared（IR），X-ray diffraction（XRD），and scanning electron microscopy（SEM）.Result indicated that the optimum conditions were as follows: the main impurity of Fe，Al，Mg，and Ca were removed by step-by-step chemical precipitation in the pure water system and then precipitation by ammonium carbonate subsequently.The ICP result showed the lithium carbonate was loose and white and its purity was more than 99.90%.The IR and XRD spectra showed there was zabuyelite type lithium carbonate only，and the lithium carbonate particles were uniform rods with 3~5 μm in length and below 0.5 μm in diameter. 

Key words: high purity lithium carbonate, fractional chemical precipitation, coarse lithium carbonate