汞是温度计及多种医用仪表的重要原料,汞的纯度对医用仪表的质量有重大的影响。丁官忠曾用真空蒸馏-发射光谱法测定过高纯汞中的杂质,样品中一般含有铜、锌、镁、钙、镉、铁、铝、铅、锡、硅等杂质,在常压下它们的沸点如表1所示。可见,利用它们间沸点的较大差别,以蒸馏法可将汞与杂质元素分离,但按Kuehner亚沸蒸馏原理,若在沸腾下蒸发汞,杂质 Mercury is an important raw material for thermometers and various medical instruments. The purity of mercury has a significant impact on the quality of medical instrumentation. Ding Guanzhong has used vacuum distillation - emission spectrometry for the determination of impurities in excessively pure mercury. The samples generally contain impurities such as copper, zinc, magnesium, calcium, cadmium, iron, aluminum, lead, tin and silicon at atmospheric pressure The boiling point is shown in Table 1. Can be seen that the use of large differences between their boiling point, distillation and mercury can be separated from the impurity elements, but according to Kuehner sub-boiling distillation principle, if the boiling under the evaporation of mercury, impurities