What are the detection methods of heavy metals?

Atomic absorption spectrometry is a new instrumental analysis method founded in 1950s. It supplements atomic emission spectrometry, which is mainly used for qualitative analysis of inorganic elements, and becomes the main means for quantitative analysis of inorganic compounds.

Second, ultraviolet-visible spectrophotometry

The detection principle is that heavy metals and chromogenic agents-usually organic compounds-can complex with heavy metals to form colored molecular groups, and the color depth of the solution is directly proportional to the concentration. At a specific wavelength, colorimetric detection is carried out.

Three, atomic fluorescence spectrometry

Atomic fluorescence spectrometry (AFS) is a method to determine the content of the elements to be measured by measuring the fluorescence emission intensity of atomic vapor of the elements to be measured under the excitation of radiation energy at a specific frequency.

Fourth, electrochemical method-anodic stripping voltammetry

Electrochemical method is a method that has developed rapidly in recent years. It relies on classical polarography, and on this basis, it derives polarography, anodic stripping voltammetry and other methods. Electrochemical method has low detection limit and high sensitivity, which is worth popularizing and applying. For example, the fifth method for determining lead and the second method for determining chromium in the national standard are oscillopolarography.

Verb (abbreviation of verb) X-ray fluorescence spectrometry

X-ray fluorescence spectrometry is a method for qualitative or quantitative determination of components in a sample by using the X-ray absorption of the sample to change with the change and quantity of components in the sample.

It has the characteristics of fast analysis speed, simple sample pretreatment, wide range of analyzable elements, simple spectral lines, less spectral interference, diverse sample forms and nondestructive determination. It can be used not only for qualitative and quantitative analysis of major elements, but also for the determination of trace elements. The detection limit is 10-6.

The above contents refer to Baidu Encyclopedia-Heavy Metal Detection.