(中南大學 冶金科學與工程學院，長沙 410083)
摘 要: 繪制了25℃時CaCl2-Ca(OH)2-H2O體系的c(CaCl2)—c(Ca(OH)2)圖和c(CaCl2)—pH值圖。結果表明：體系中c(Ca(OH)2)和pH值隨著c(CaCl2)的增加而不斷減小, c(Ca(OH)2)變化趨勢與Debye-Huckel計算值相符，當c(CaCl2)＜3.78 mol/L時，體系pH值＞10.4。當c(CaCl2)＞2.57mol/L時，有沉淀物CaClOH生成。經(jīng)計算，理論上CaCl2母液可以循環(huán)配制石灰水132次，研究結果為石灰水法制備氫氧化鎂工藝中CaCl2母液循環(huán)配制石灰水提供了一定的理論依據(jù)。
關鍵字: CaCl2-Ca(OH)2-H2O；石灰水；CaCl2母液；pH值；循環(huán)
（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
