文献类型：期刊文献

英文题名：Phase Equilibrium of the Ternary System K2SO4-KOH-H2O at 313.15, 333.15, 343.15, and 353.15 K

作者：Luo, Mengjie[1];Ye, Junxiang[1];Liu, Chenglin[1];Song, Xingfu[1];Yu, Jianguo[1]

机构：[1]East China Univ Sci & Technol, Engn Res Ctr Resource Salt Lake Proc Engn, Minist Educ, Sch Resources & Environm Engn, Shanghai 200237, Peoples R China

年份：2020

卷号：65

期号：5

起止页码：2458

外文期刊名：JOURNAL OF CHEMICAL AND ENGINEERING DATA

收录：;EI(收录号：20202008647381);WOS:【SCI-EXPANDED(收录号:WOS:000535280900020)】；

基金：The authors wish to acknowledge the National Natural Science Foundation of China (grant 21908064), China Postdoctoral Science Foundation (Grant 2018M641940), and Program of Shanghai Academic/Technology Research Leader (grant 18XD1424600) for the financial support.

语种：英文

外文关键词：Phase equilibria - Temperature - Isotherms - Potassium hydroxide - Solubility - Ionic strength - Dissolution

摘要：The phase equilibrium of the ternary system K2SO4-KOH-H2O at 313.15, 333.15, 343.15, and 353.15 K was researched by the isothermal dissolution method. There are one invariant point, two univariant isothermal dissolution curves, and three crystallization regions. Neither double salt nor solid solution is found in the ternary system. At the invariant point of the ternary system, the composition of the solution is K2SO4 0.03 and KOH 56.03 wt % at 313.15 K, K2SO4 0.07 and KOH 57.21 wt % at 333.15 K, K2SO4 0.08 and KOH 58.56 wt % at 343.15 K, and K2SO4 0.09 and KOH 59.48 wt % at 353.15 K, respectively. According to the phase diagrams of the ternary system, it can be indicated that high KOH concentration and low temperature are beneficial to separating K2SO4 from the alkali solution. Furthermore, the solubilities corresponding to the crystallization region of K2SO4 in the ternary system at each temperature were calculated theoretically by using the Pitzer ion interaction model. The calculated K2SO4 solubilities basically agree with experimental values at low KOH concentration. However, the high ionic strength was found to be a key factor that seriously influenced the calculation accuracy. All the data obtained in this work are significant to the design and optimization of the K2SO4 crystallization process from the alkaline leaching solution in the alunite metallurgical industry.