( 1. 中南大學(xué) 冶金科學(xué)與工程學(xué)院，長(zhǎng)沙 410083；
2. 湖南冶金職業(yè)技術(shù)學(xué)院 冶金系， 株洲 412000)
摘 要: 采用等溫溶解平衡法， 研究了Mn2+-NH＋4-SO2-4-H2O三元體系在298 K下的相平衡及其平衡液相的主要物理化學(xué)性質(zhì)（密度和pH值）， 繪制了溶解度平衡相圖及物化性質(zhì)組成圖。結(jié)果表明： 在三元體系Mn2+-NH＋4-SO2-4-H2O相圖中存在3條飽和曲線、 2個(gè)共飽和點(diǎn)及3個(gè)純鹽結(jié)晶區(qū)。根據(jù)經(jīng)驗(yàn)公式對(duì)平衡液相的密度進(jìn)行了計(jì)算， 計(jì)算值與實(shí)驗(yàn)測(cè)定結(jié)果的變化趨勢(shì)相一致， 但少數(shù)計(jì)算值的相對(duì)誤差較大。
關(guān)鍵字: 水鹽體系; 溶解度; 相平衡
Mn2+-NH＋4SO2-4-H2O system
（ 1. School of Metallurgical Science and Engineering,
Central South University, Changsha 410083, China;
2. Metallurgical Department, Hunan Metallurgical and
Professional Institute, Zhuzhou 412000, China）
Abstract: The solubility and physicochemical properties of solution, such as density and pH value, were studied in the ternary system of Mn2+-NH＋4-
SO2-4-H2O at 298 K by isothermal equilibrium method. According to the experimental data and calculated ones, the phase diagram and density-composition and pH-composition curves of the system were plotted. The results show that in the ternary system of Mn2+-NH＋4-SO2-4-H2O, there exist three saturated curves, two co-saturated points and three purity salt crystal areas. The density values were calculated by the experimental formulas and were also measured. The calculated values are not all in agreement with the experimental results.
Key words: salt-water system; solubility; phase equilibrium
