In this study, the gas‒liquid reactive crystallization of LiCl–NH₃·H₂O–CO₂ was adopted to produce Li₂CO₃. The weakly alkaline nature of NH₃·H₂O in the absence of any recarbonation process resulted in a unimodal and easily controllable particle size distribution (PSD) of the obtained Li₂CO₃. The reaction temperature significantly influenced both the Li₂CO₃ particle size and PSD. By increasing the temperature from 25 to 60 °C, the volume weighted mean particle size increased from 50.5 to 100.5 μm, respectively. The Li₂CO₃ secondary nucleation rate and growth rate were obtained by focused beam reflectance measurements and a laser particle size analyzer, respectively. The secondary nucleation rate of Li₂CO₃ reduced as a function of temperature, whereas the growth rate increased. In addition to improving the surface energy of the crystals to enhance the growth process, higher temperatures also reduced the supersolubility of Li₂CO₃, which also plays a role to decrease the secondary nucleation rate. At a constant temperature, supersaturation affects the Li₂CO₃ particle size through the synergistic effect of secondary nucleation and growth. Hence, with improved supersaturation, the mean particle size of Li₂CO₃ decreased. The results provide a meaningful way to evaluate the crystallization process and to regulate the particle size.

本研究采用LiCl–NH ₃ ·H ₂ O–CO ₂的气液反应结晶法制备Li ₂ CO ₃。在没有任何再碳酸化过程的情况下，NH ₃ ·H ₂ O的弱碱性导致所获得的Li ₂ CO ₃的单峰且易于控制的粒度分布（PSD）。反应温度显着影响Li ₂ CO ₃粒径和PSD。通过将温度从25℃提高到60℃，体积加权平均粒径分别从50.5μm增加到100.5μm。Li ₂ CO通过聚焦光束反射率测量和激光粒度分析仪分别获得₃次晶核形成速率和生长速率。Li ₂ CO ₃的二次成核速率随温度降低，而生长速率增加。高温除了改善晶体的表面能以增强生长过程外，还降低了Li ₂ CO ₃的超溶解度，这也起到降低二次成核率的作用。在恒定温度下，过饱和会影响Li ₂ CO ₃通过二次成核和生长的协同作用获得的颗粒尺寸。因此，随着过饱和度的提高，Li ₂ CO ₃的平均粒径减小。结果为评估结晶过程和调节粒径提供了有意义的方法。