盐湖卤水碳酸锂提取工艺过程研究

青藏高原的盐湖卤水锂储量丰富，通过盐田蒸发浓缩，去除卤水中的绝大部分Na+、K+、SO42-、Cl-、Mg2+，可以使镁锂比降到8～12，锂离子质量分数也可达到0.5%以上。以蒸发浓缩后的富锂卤水为原料，选用碳酸钠和氢氧化钠为沉淀剂分两步沉淀除镁，之后用碳酸钠为沉淀剂提锂，通过对此工艺过程中的各个阶段进行实验，最终可以得到纯度和收率较高的粗级碳酸锂产品。

Research on extraction process of lithium carbonate from salt lake brine

The salt lake brine in Tibetan Plateau has a rich lithium reserves.After the process of evaporation in the salt pan， the most impurities，such as Na⁺，K⁺，SO₄^2-，Cl^-，and Mg²⁺ in the brine can be removed.At the same time，the ratio of Mg/Li is decreased to the range of 8~12 and the mass fraction of lithium ion can be concentrated to over 0.5%.The magnesium ions in the evaporated lithium-rich brine are precipitated with the sodium carbonate and sodium hydroxide as precipitators，and then the lithium is extracted with sodium carbonate as precipitator.After a series of experiments in all the stages of the process，coarse lithium carbonate with relatively higher purity and yield is finally obtained.