Mn^(2+)-Dipy-SCN^-共沉淀分离—拉曼光谱法测定水中镉的研究

Research on fast determination of heavy metal Cd using the Mn^(2+)-Dipy-SCN^-co-precipitation separation and Raman spectroscopy

人体饮用水的同时会摄入水中的重金属。使用拉曼光谱技术,并采用Mn2+-Dipy(2-2’联吡啶)-SCN-共沉淀分离的方法,能检测水中重金属镉。根据对比不同光谱数据预处理方法,并结合偏最小二乘法建立定量模型。实验结果为,光谱信息经过二阶微分处理后的建模效果较理想,其外部验证相关系数为0.915 6,预测均方根误差为0.011 9。采用HM—5000P重金属分析仪测定共沉淀前后重金属镉离子的含量,发现Mn2+-Dipy-SCN-络合体系对水中镉离子的回收率超过90%,最高可达99.781%。实验表明,Mn2+-Dipy-SCN-三元络合物共沉淀体系对重金属镉有很好的分离效果,Mn2+-Dipy-SCN-共沉淀分离拉曼光谱法用于重金属镉的检测具有可行性。

The important way that heavy metal enters the human body is drinking water.The heavy metal enters the body is another important way for drinking water.For fast determination of Cd,the Mn^2＋-Dipy-SCN^-co-precipitation separation is used,combined with confocal microscope Raman spectroscopy.Different preprocessing methods were compared,combined with partial least squares（PLS）,and the quantitative model was established.The result showed that the best model was obtained by PLS with the preprocessing method of second-order differential,external validation correlation coefficient（r）and root mean square error of prediction（RMSEP）was 0.915 6and 0.011 9.The HM—5000Pheavy metals analyzer was used to determine the content of Cd before and after the Mn^2＋-Dipy-SCN^-co-precipitation separation,and observed that recovery rate of Cd2＋range from 90%to 99.781%.The experiment shows that the Mn^2＋-Dipy-SCN^-ternary complex co-precipitation systems have good concentration effects for Cd2＋,the fast determination of Heavy Metal Cd using the Mn^2＋-Dipy-SCN^-co-precipitation separation and Raman spectroscopy is feasible.