Abstract: The solubilites of H3BO3-MgSO4-MgC12-H2O systems at 25°and 100℃ determined and the phase diagrams are plotted.On the basis of these diagrams,in evaporation of the aqueous solution of H3BO3-MgSO4,with MgC12 as salting out agent,MgSO4·H2O can be precipitated.On cooling down the MgSO4 mother liquor,boric acid can be crystallized out.The H3BO3 mother liquor can be recycled and used as salting out sgent againn,thus H3BO3 and MgSO4 can be throughly separated.In this paper,the optimum concentration of MgCl2 is also discussed.

摘要： 测定了25℃、100℃H_3BO_3-MgSO_4-MgCl_2-H_2O体系的溶解度并绘成相图.根据相图，H_3BO_3-MgSO_4溶液可以MgCl_2为盐析剂，在100℃下蒸发析出一水硫酸镁，其母液冷至25℃析出H_3BO_3，硼酸母液循环用作盐析剂，使H_3BO_3和MgSO_4完全分离．文中并讨论了MgCl_2的最适用量.