高校化学工程学报2026，Vol.40Issue(3)：418-431,14.DOI:10.3969/j.issn.1003-9015.2025.00.064
无水硫酸镁在H2O-乙二醇二元体系中的结晶热力学
Crystallization thermodynamics of anhydrous magnesium sulfate in H2O-ethylene glycol binary system
摘要
Abstract
For understanding the microscopic interactions of electrolytes in mixed aqueous environments,this study systematically investigated the crystallization thermodynamics of anhydrous magnesium sulfate(MgSO4)in a water-ethylene glycol(H2O/EG)binary solvent system.The solubility,supersolubility,and metastable zone width(MSZW)were determined using the dynamic laser method across varying temperatures(303.15-333.15 K)and solvent compositions(H2O∶EG molar ratios ranging from 9∶1 to 1∶9).Key findings revealed that MgSO4 solubility increases with temperature but decreases with rising EG content.Adsorption of EG on crystal surfaces creates steric hindrance,significantly broadening the metastable zone.Among five evaluated thermodynamic models(Apelblat,Van't Hoff,Redlich-Kister,polynomial,Jouyban-Acree-Van't Hoff),the polynomial model exhibited optimal correlation(R2＞0.99),while the Jouyban-Acree-Van't Hoff(JAVH)model enabled precise full-condition prediction.Thermodynamic analysis confirms an endothermic process(ΔdisH0＞0)dominated by enthalpy changes and non-spontaneous dissolution(ΔdisG0＞0).A surface entropy factor(f＞5)indicated a spiral growth mechanism,consistent with the decreasing interfacial tension(γ)trend at lower temperatures.Density and apparent molar volume data confirmed weakened solute-solvent interactions at elevated temperatures.Agitation narrows the metastable zone by enhancing mass transfer,whereas rapid cooling broadens it due to localized supersaturation.The 3D classical nucleation model demonstrated superior accuracy in predicting MSZW.These findings deepen fundamental insights into MgSO4 behavior in mixed solvents and provide critical data for optimizing industrial crystallization processes and designing functional materials.关键词
无水硫酸镁/溶解度/结晶热力学/介稳区/水-乙二醇体系Key words
anhydrous magnesium sulfate/solubility/crystallization thermodynamics/metastable zone/water-ethylene glycol mixtures分类
化学化工引用本文复制引用
吕豪,刘曦悦,谭晶晶,李路云,郑雅元,邢波,杜怀明..无水硫酸镁在H2O-乙二醇二元体系中的结晶热力学[J].高校化学工程学报,2026,40(3):418-431,14.基金项目
四川省科技教育联合基金(2025NSFSC2070) （2025NSFSC2070）
四川省科技计划项目(2020YFG0163) （2020YFG0163）
精细化工应用技术泸州市重点实验室(HYJH-2305-B) （HYJH-2305-B）
四川省研究生创新基金(Y2024103) （Y2024103）
钒钛资源综合利用四川省重点实验室项目(2018FTSZ13). （2018FTSZ13）
