基于水溶性探针法测镁的高纯碳酸锂快速质检

碳酸锂生产过程及最终产品中，微量镁的掺杂会直接影响碳酸锂的产品品质及其下游产品的加工应用，而高纯碳酸锂中微量镁的快速检测仍是一个难点。研究提出利用水溶性荧光探针检测碳酸锂中微量镁的方法，以水溶性极强的三(羟甲基)氨基甲烷对2-(2-羟基苯基)苯并噁唑进行修饰，构建了具有高灵敏度和高选择性的水溶性Mg²⁺荧光探针A。该方法可实现对碳酸锂溶液中Mg²⁺的快速荧光检测，并确定了探针A被Mg²⁺所激发的荧光信号强度与Mg²⁺浓度之间的定量关系。结果表明在水溶条件下检测含镁杂质的碳酸锂时，该方法对微量镁的检出限为2.014 9μmol/L，检测工作曲线相关系数达到0.991 5，检测灵敏度高，对高纯碳酸锂中微量镁的检测时间为3.666 s，可实现对Mg²⁺的快速质检。

Rapid quality inspection of high-purity lithium carbonate based on determination of magnesium by water-soluble probe method

In the production process of lithium carbonate and the final product，the doping of trace magnesium will directly affect the product quality of lithium carbonate and the processing and application of downstream products，and the rapid detection of trace magnesium in high-purity lithium carbonate is still a difficulty.In this study，a method for detecting trace amounts of magnesium in lithium carbonate using a water-soluble fluorescent probe was proposed.The highly water-soluble tris（hydroxy） methyl aminomethane was used to modify 2-（2-hydroxyphenyl） benzoxazole.Water-soluble Mg²⁺ fluorescent probe A with high sensitivity and selectivity was constructed.This method could realize the rapid fluorescence detection of Mg²⁺ in lithium carbonate solution，and determine the quantitative relationship between the fluorescence signal intensity of probe A excited by Mg²⁺ and the concentration of Mg²⁺.The results showed that the detection limit of this method for trace magnesium was 2.014 9 μmol/L when the lithium carbonate containing magnesium impurities was detected under water-soluble conditions，and the correlation coefficient of the detection working curve reached 0.991 5，and the detection sensitivity was high.The detection time of magnesium was 3.666 s，which could realize the rapid quality inspection of Mg²⁺.