Based on the isothermal solution equilibrium method, a systematic study of the quaternary (Li⁺, NH₄⁺//Cl⁻, SO₄²⁻-H₂O) and its subsystems ((NH₄)₂SO₄-NH₄Cl-H₂O, NH₄Cl-LiCl-H₂O and (NH₄)₂SO₄-Li₂SO₄-H₂O) at 288.15 K were undertaken. The phase diagrams of these systems were drawn by the experimental solubility data. The ternary system (NH₄)₂SO₄-NH₄Cl-H₂O is a simple system at 288.15 K while solid solution (LiCl•2H₂O)_x(NH₄Cl)_1-x was formed in the ternary system NH₄Cl-LiCl-H₂O. The compound salt LiNH₄SO₄ and solid solution (Li₂SO₄•H₂O)_x(LiNH₄SO₄)_1-x were produced in the system (NH₄)₂SO₄-Li₂SO₄-H₂O. The phase diagram of the quaternary system (Li⁺, NH₄⁺//Cl⁻, SO₄²⁻-H₂O) include seven solid phase crystallization regions (NH₄Cl, LiCl•2H₂O, (LiCl•2H₂O)_x(NH₄Cl)_1-x, Li₂SO₄•H₂O, (NH₄)₂SO₄, LiNH₄SO₄ and (Li₂SO₄•H₂O)_x(LiNH₄SO₄)_1-x).

基于等温溶液平衡的方法，所述季铵的系统研究（栗⁺，NH ₄ ⁺ //氯^-，SO ₄ ^2- -H ₂ O）及其子系统（（NH ₄）₂ SO ₄ -NH ₄氯在288.15K下进行-H ₂ O，NH ₄ Cl-LiCl-H ₂ O和（NH ₄）₂ SO ₄ -Li ₂ SO ₄ -H ₂ O）。这些系统的相图是通过实验溶解度数据绘制的。三元体系（NH ₄）₂ SO ₄ -NH ₄ Cl-H ₂ O是在288.15 K下的简单系统，而固溶（LiCl•2H ₂ O）_x（NH ₄ Cl）_1-x在三元体系NH ₄ Cl-LiCl-中形成ħ ₂ O的化合物的盐灵₄ SO ₄和固体溶液（栗₂ SO ₄ •水平₂ O）_X（灵₄ SO ₄）_1-x中的系统制作（NH ₄）₂ SO ₄ -Li ₂SO ₄ -H ₂的四元体系的O的相图（李⁺，NH ₄ ⁺ //氯^-，SO ₄ ^2- -H ₂ O）包括七个固相结晶化区域（NH ₄氯，氯化锂•2H ₂ O，（LiCl•2H ₂ O）_x（NH ₄ Cl）_1-x，Li ₂ SO ₄ •H ₂ O，（NH ₄）₂ SO ₄，LiNH ₄ SO ₄和（Li ₂ SO ₄ •H₂ O）_x（LiNH ₄ SO ₄）_1-x）。