相转移-碳化法合成纳米轻质碳酸钙的工艺条件

Study of preparation process of light calcium carbonate via phase transfer and carbonation route

文章以氧化钙为原料,采用相转移-碳化法制备轻质碳酸钙。通过单因素条件实验和正交实验,考察了相转移剂与钙离子的摩尔比、钙离子浓度、碳化温度及碳化时间等工艺条件对碳酸钙产率的影响,记录了反应过程中体系pH值的变化,所确定较适宜的相转移-碳化反应工艺条件为:相转移剂与钙离子的摩尔比为4∶1、氧化钙浓度为0.5mol/L、碳化温度为60℃、碳化时间为2.5h,该条件下纳米碳酸钙的产率平均值为96.3%;采用XRD、TEM、FESEM、粒度分析和红外光谱等对所制得的纳米碳酸钙样品进行表征。

In this paper ,light calcium carbonate was prepared via the phase transfer and carbonization route ,using calcium oxide as the raw material .Taking the yield of the as-prepared calcium carbonate as the main index ,the carbonization conditions ,such as the ratio of phase transfer agent to calcium ion ,the concentration of calcium ion ,carbonization time and temperature ,were investigated by sin-gle-factor and orthogonal experiments .The change of the pH value in the process of reaction was ob-served .T he optimum conditions are obtained as follow s ：the ratio of phase transfer agent to calcium ion is 4∶1 ,the concentration of calcium oxide is 0.5 mol/L ,the carbonization time is 2.5 h ,the car-bonization temperature is 60 ℃ .The average yield of the calcium carbonate under optimum reaction conditions can reach to 96.3% .The as-prepared light calcium carbonate was characterized by X-ray diffraction（XRD） ,transmission electron microscope （TEM ） ,field emission scanning electron micro-scope（FESEM ） ,laser particle size analyzer and Fourier transform infrared spectroscopy （FT-IR） .