三元体系MgSO4-FeSO4-H2O的相平衡研究.pdf

第45卷第1期
化学工程
2017年1月
CHEMICAL ENGINEERING( CHINA
Jan.2017
元体系 Mgso4-FeSO4-H2O的相平衡研究
张宁婕,朱家文,陈荽,范先国,周晚荽
(1.华东理工大学化工学院,上海200237;2.四川龙蟒集团,四川I绵竹618200)
摘要:从钛白废酸与磷矿浮选尾矿中提取的铁、镁反应制备硫酸亚铁镁,反应主要涉及Mg2-,Fe2~//S
体
系,因此开展该体系相平衡研究对综合利用工业废料,并使其转化成环保且具有经济价值的复合肥料意义重大
文中采用等温溶解平衡法测定了三元体系MgSO4-FeS02-H20在293.15,303.15,313.15K下的溶解度数据以及平
衡溶液液相的密度,采用化学分析和X射线衍射法对结品湿渣进行了分析,并依据相乎衡数据绘制了相图。实验
发现:在293.15,303.15,313.15K下,该三元体系不存在单盐区和复盐区,固溶体[(Fe,Mg)SO4?7H12O]古据了整
个相区。在固溶体[(Fe,Mg)SO,?7H2?]中,Mg3与Fe:在晶体中可以任意比例互換,形成完全类质同像系列
物。因此,在293.15,303.15,313.15K下很难采用单一的发结晶方法从硫酸亚铁镁溶液中分离出硫酸镁和硫酸
亚铁晶体:同时,若要获得单一配比的硫酸亚铁镁晶体,需要严格控制原料液中的Mg/Fe比例。
关键词:水盐相图;溶解度;结晶;固溶体
中图分类号:0642文献标识码:A文章编号:1005-9954(2017)01-03604
DOI:10.3969/j.iss.-1005954.2017.01.008
Metastable phase equilibrium in the aqueous ternary system
Mgso. -Feso4
ZHANG Yu jie ZHU Jia-wen CHEN Kui , FAN Xian- uo ZHOU Xiaokui
(1. College of Chemical Engineerin East China University of Scicnce and Technology, Shanghai 200237, China
2. Sichuan Lomon Corporation, Mianzhu 618200, Sichuan Province, China
Abstract: The titanium white waste acid and phosphate rock flotation tailings were changed into M, Fe.//S.
ternary system after the iron and magnesium were crystallized and separated, and the phase equilibrium research on
the ternary system Mgso, -Feso, -, O was essential to convert industrial wastes to environmentally friendly
conpound fertilizer which also had significant economic value. The metastable phase equilibrium in the temary
stem Mgs0-fes0-h,0 was investigated at 293. 15 K, 303. 15 K and 313. 15 K using an isothermal evaporation
method. The solubilities and densities of the equilibrated solution were measured. The crystalloid forms of the solid
ase were determined using chemical analysis and an X-ray diffraction method. The results show that the ternary
system belongs to the complete isomorphous series, and double salls are not found at the investigated temperature
The crystallization region of the solid solution [(Fe, Mg)SO.7H20] occupies the entire phase region. In the
solid solution, Mg2"and Fe?"can be interchanged in any proportion. Thus, it is difficult to separate epsomite fro
ferrous sulfate solution by only using evaporation and crystallization methods at 293. 15 K, 303.15 K and 313.15
K. During the preparation of a fixed ratio of ferrous sulfate magnesium crystals, the Mg/ Fe ratio in raw material
liquid should be strictly controlled
Key words: water-salt system phase diagram; solubility; crystallization; solid solution
中国磷矿资源丰富,但多数属于中低品位礫矿,选后将会产生大量的浮选尾矿,尾矿中u(P2O。)≤
通常采用化学浮选方法富集磷矿。憐矿经过化学浮10%,c(MIgO)≥15%。日前,这些磷矿浮选尾矿人
收稿日期:2016-04-1
基金项目:上海市科学委员会资功项目(151958000
作者简介:张宇婕(191-),女,硬土研究生,研究方向为水盐相图与结晶:陈,副教授,通信联系人,E, mail. shenkui ecust.n
万方数据