(中南大学 冶金科学与工程学院，长沙 410083)
摘 要: 绘制了25℃时CaCl2-Ca(OH)2-H2O体系的c(CaCl2)—c(Ca(OH)2)图和c(CaCl2)—pH值图。结果表明：体系中c(Ca(OH)2)和pH值随着c(CaCl2)的增加而不断减小, c(Ca(OH)2)变化趋势与Debye-Huckel计算值相符，当c(CaCl2)＜3.78 mol/L时，体系pH值＞10.4。当c(CaCl2)＞2.57mol/L时，有沉淀物CaClOH生成。经计算，理论上CaCl2母液可以循环配制石灰水132次，研究结果为石灰水法制备氢氧化镁工艺中CaCl2母液循环配制石灰水提供了一定的理论依据。
关键字: CaCl2-Ca(OH)2-H2O；石灰水；CaCl2母液；pH值；循环
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The c(CaCl2)—c(Ca(OH)2) chart and c(CaCl2)—pH value chart in CaCl2-Ca(OH)2-H2O system under 25 ℃ were plotted. The results represent that c(Ca(OH)2) and pH value decrease with the increase of c(CaCl2), the trend of c(Ca(OH)2) is supported by the calculation results of Debye-Huckel. When c(CaCl2)＜3.78 mol/L, the pH value of the system is bigger than 10.4, and CaClOH is preciptated while c(CaCl2)＞2.57 mol/L. Through calculation, the CaCl2 mother liquor can reuse 132 times for collocating lime water in theory. The research results provide a theoretical basis for the treatment and reuse of calcium chloride mother liquor for collocating lime water which is the precipitant in the process of synthesizing magnesium hydroxide.
Key words: CaCl2-Ca(OH)2-H2O; lime water; CaCl2 mother liquor; pH value; recycling
