中南大学学报（自然科学版）2013，Vol.44Issue(7)：2681-2687,7.
乙醇结晶法提取硼铁矿酸浸液中的硫酸镁
Extracting magnesium sulfate from acid-leaching solution of ludwigite by ethanol crystallization
摘要
Abstract
A new method that magnesium sulfate crystal extracted from acid-leaching solution of ludwigite using ethanol was proposed,and the feasibility of this method was discussed by calculating the enthalpy change (△Hs) and Gibbs free energy change (△Gs) of dissolving process and the solvation energy of magnesium sulfate both in water and water-ethanol.The effects of pH,crystallization temperature,the amount of ethanol and the initial concentration of magnesium sulfate on the crystallization rate of magnesium sulfate in ethanol-water were also discussed.The results show that the optimum processing parameters of magnesium sulfate crystallization in water-ethanol mixture are that the pH of solution is between 1.5 and 2.0,the volume ratio of solution to ethanol is 1∶1.5,the crystallization temperature is room temperature and the initial concentration of magnesium sulfate is greater than 1.5 mol/L.Under this condition,the crystallization rate of magnesium sulfate can reach 97.73％.The product is determined as magnesium sulfate heptahydrate by XRD and TG,and the purity of it is 99.10％,which fits the first grade of class Ⅰ industrial products under the chemical industrial standard of China (HG/T 2680-2009) for magnesium sulfate heptahydrate.关键词
硼铁矿/水-乙醇相/溶剂化/溶剂化能/七水硫酸镁Key words
ludwigite/ water-ethanol/ solvation/ solvation energy/ magnesium sulfate heptahydrate分类
矿业与冶金引用本文复制引用
张丽清,袁本福,周华锋,刘志国..乙醇结晶法提取硼铁矿酸浸液中的硫酸镁[J].中南大学学报（自然科学版）,2013,44(7):2681-2687,7.基金项目
辽宁省教育厅科学研究计划基金资助项目(05L336) （05L336）
辽宁省高校硼资源生态化综合利用与硼材料重点实验室资助项目(200602) （200602）
