Cheng Huaide, Hai Qingyu, Song Jianguo, Ma Xuehai, Li Changzhong
Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lake, Chinese Academy of Sciences Xining 810008 China
Key Laboratory of Salt Lake Geology and Environment of Qinghai Province Xining 810008 China.
RSC Adv. 2020 May 29;10(35):20529-20535. doi: 10.1039/d0ra03567j. eCollection 2020 May 27.
The amount of water is the crucial factor for the decomposition of carnallite in aqueous solution. A novel method for monitoring the decomposition process of carnallite in aqueous solution based on the Mg value and moisture content of the decomposed products was investigated in this study. Based on the principle of mass conservation of MgCl during the decomposition of carnallite in aqueous solution, a functional model of Mg value in decomposed products was established. The functional model of moisture content in decomposed products was obtained by the water equilibrium condition of the reaction system. The experiments were performed by dissolving carnallite in aqueous solution under different water conditions, and the Mg value and moisture content were determined for the decomposed products. The results showed that: (1) the Mg value and moisture content of the decomposed products have a nonlinear variation when the amount of water used to dissolve carnallite is not suitable, and (2) an excess amount of water used to dissolve carnallite would lead to a linear change in the Mg value and moisture content of the decomposed products. It was found that the intersection of these two changes is the appropriate location for the decomposition of carnallite in aqueous solution. The Mg value and moisture content of the decomposed products are thus presented as a novel monitoring method for these applications within the potash processing industry.
水量是光卤石在水溶液中分解的关键因素。本研究探索了一种基于分解产物的镁含量和水分含量来监测光卤石在水溶液中分解过程的新方法。基于光卤石在水溶液中分解过程中氯化镁的质量守恒原理，建立了分解产物中镁含量的函数模型。通过反应体系的水平衡条件得到了分解产物中水分含量的函数模型。通过在不同水分条件下将光卤石溶解于水溶液中进行实验，并测定分解产物的镁含量和水分含量。结果表明：（1）当用于溶解光卤石的水量不适当时，分解产物的镁含量和水分含量呈非线性变化；（2）用于溶解光卤石的水量过多会导致分解产物的镁含量和水分含量呈线性变化。发现这两种变化的交点是光卤石在水溶液中分解的合适位置。因此，分解产物的镁含量和水分含量可作为钾盐加工行业中这些应用的一种新型监测方法。
