Over the world, the available lithium (Li) resources are reserved mainly in closed-basin brines, with high Li concentration (> 150 mg/L) and low Mg/Li ratio (< 10) being critical for Li extraction using precipitation-based methods. In order to investigate the enrichment of Li over Mg during the formation of Li brine deposits, batch water–rock interacting experiments between igneous rocks and aqueous solutions were carried out under low (25, 50 and 75 °C) and high (200, 300 and 400 °C) temperature conditions. Our results show that for the experiments using water and accomplished under 25 °C, the Mg and Li concentrations vary from 0.470 and 0.782 mg/L in the solution interacted with Li-rich granite, to 5.626 and < 0.002 mg/L in that interacted with basalt, with Mg/Li ratio being slightly higher than those of the igneous rocks. By contrast, while a NaCl or Na₂SO₄ solution was used, the Mg and Li concentrations can be improved by up to tens of times, and the Mg/Li ratio also increased slightly. Lastly and above all, with increase in the water–rock interacting temperature from 25 to 400 °C, the Mg and Li concentrations in all solutions vary conversely and the Mg/Li ratio decreases by orders of magnitude, leading to the formation of Li-rich brines with very low Mg/Li ratios at temperatures above 200 °C. By comparing the results from our experiment to those from Li-rich springs, rivers and closed-basin brines, we conclude that water evaporation over time is fundamental for the concentration of Li in brines, meanwhile high-temperature hydrothermal processes are key to the formation of Li brine deposits with low Mg/Li ratios.

世界范围内，可用锂资源主要赋存于闭盆卤水中，高锂浓度（> 150 mg/L）和低镁锂比（< 10）对于沉淀法提取锂至关重要。方法。为了研究锂卤水矿床形成过程中锂相对镁的富集情况，在低温（25、50和75℃）和高温（200、300℃）下开展了火成岩与水溶液之间的批量水岩相互作用实验。和400°C）温度条件。我们的结果表明，对于在 25 °C 下完成的使用水的实验，Mg 和 Li 浓度从与富锂花岗岩相互作用的溶液中的 0.470 和 0.782 mg/L 变化到与富锂花岗岩相互作用的溶液中的 5.626 和 < 0.002 mg/L。玄武岩，镁锂比略高于火成岩。相比之下，当使用NaCl或Na ₂ SO ₄溶液时，Mg和Li浓度可提高数十倍，并且Mg/Li比也略有增加。最后也是最重要的是，随着水-岩相互作用温度从 25°C 升高到 400°C，所有溶液中的 Mg 和 Li 浓度发生相反变化，并且 Mg/Li 比率下降几个数量级，导致 Li- 的形成。温度高于 200 °C 时，富含镁/锂比的盐水。通过将我们的实验结果与富锂泉水、河流和闭盆卤水的结果进行比较，我们得出结论，随着时间的推移，水的蒸发是卤水中锂富集的基础，而高温热液过程是形成的关键。低镁/锂比的锂卤水矿床。