分光光度法快速测定碳化液中钙离子的含量

Rapid Determination of Content of Calcium Ions in Carbonated Solution by Spectrophotometry

在570 nm波长处,钙离子与偶氮氯膦(Ⅰ)生成1∶1红色络合物,钙离子质量浓度在0～50μg/mL范围内符合比尔定律,工作曲线的回归方程为y=0.384 9x-0.006 8,相关系数R2=0.999 6,从工作曲线计算的此法的表观摩尔吸光系数ε570 nm=1.54×104L/(mol.cm)。该法可用于测定硝酸钙溶液制备轻质碳酸钙产品工艺过程中碳化后溶液中钙离子的含量,以确定产品中碳酸钙的含量,具有操作简单、可行性强的特点,可以满足实时监控的要求。

At a wavelength of 570 nm calcium ions and chlorophosphonazo （ I ） form a 1：1 red complex, the mass concentration of calcium ions is in the range of 0 - 50 μg/mL, conforming to the Beer＇s law, the regression equation of the working curve is y = 0. 384 9x -0. 006 8, the correlation coefficient R2 = 0.999 6, and calculated from the working curve, the apparent molar absorptivity of this method ε270nm = 1.54× 10^4 L/（mol·cm）. This method can be used to determine the content of calcium ions in the carbonated solution in the process of the preparation of light calcium carbonate product from calcium nitrate solution, so as to ascertain the calcium carbonate content in the product, and the method is simple in operation and highly feasible, meeting the requirement for real-time monitor.