软钾镁矾反应转化制备K2SO4的母液回收利用研究  

Recycling of Mother Liquor from Reaction Conversion of Picromerite for K2SO4

作　　者：朱敏[1] 陈杭[1] 宋兴福[1] 于建国[1] ZHU Min;CHEN Hang;SONG Xingfu;YU Jianguo(National Engineering Research Center for Integrated Utilization of Salt Lake Resources,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学国家盐湖综合利用工程技术研究中心,上海200237

出　　处：《华东理工大学学报（自然科学版）》2020年第4期454-463,共10页Journal of East China University of Science and Technology

基　　金：国家重点研发计划(2018YFC0604802);上海市优秀学术/技术带头人计划(18XD1424600)。

摘　　要：软钾镁矾反应结晶制备硫酸钾过程会产生大量含钾母液。为提高钾资源利用率,分别采用常压蒸发、减压蒸发和真空蒸发3种不同的结晶回收工艺,考察了温度为108、75、35℃时反应母液钾资源回收利用过程。通过化学分析、X射线多晶衍射仪(XRD)、激光粒度分布等表征方法,系统研究了3种蒸发结晶工艺路线的产物纯度、形貌与粒径指标,确定了介稳条件下钾资源回收的蒸发结晶控制终点。实验结果表明,108℃时蒸发结晶工艺产物为无水钾镁矾和氯化钾,而75℃和35℃时蒸发结晶工艺的结晶产物均为氯化钾,其中35℃时回收产物的钾质量分数及钾回收率同时达到最高,分别为44.64%和78.73%,因此,真空蒸发结晶为软钾镁矾反应转化母液钾资源回收利用的最佳工艺路线。During the reaction crystallization of picromerite for potassium sulphate,a large amount of potassiumcontaining mother liquor is produced.In order to improve the utilization of potassium resources,different crystallization strategies performed under different vacuum degrees were used to investigate the recovery and utilization of potassium resources in reaction mother liquor at 108,75,35℃.The purity,morphology and particle size distribution of the three routes of evaporation crystallization were systematically studied using XRD,chemical analysis,particle size distribution and other analytical methods.The ending point of evaporation water for potassium resource recovery under metastable conditions was determined.The experimental results show that the products of the evaporation crystallization process at 108℃ are langbenite and potassium chloride,and the crystal products at 75℃ and 35℃ are potassium chloride.At 35℃,the potassium content and potassium recovery rate of the products reach the highest within the same time,which are 44.64%and 78.73%,respectively.Meanwhile,combined with the characteristics of drought and little rain in the western salt lake area,it is determined that the evaporation crystallization at room temperature is the best process for potassium resource recovery in the mother liquor of reaction of picromerite.The experimental results provide relevant basis and reference for the further improvement of utilization of potassium resource in the resource-type potassium sulfate production process.

关 键 词：硫酸钾 软钾镁矾 反应母液 蒸发结晶 钾资源回收 

分 类 号：TQ443.2[化学工程—化学肥料工业]