Direct sample introduction type method and instrument for simultaneously measuring mercury and cadmium

Abstract

The invention relates to a direct sample introduction type method and a direct sample introduction type instrument for simultaneously measuring mercury and cadmium, which do not need to digest a sample. The direct sample introduction type method for simultaneously measuring mercury and cadmium comprises the steps of heating a sample in an aerobic environment, controlling the temperature in the scope from 120 DEG C to 500 DEG C, and separating most Hg and a decomposer out from the sample; loading Hg (mercury) and the decomposer into a catalytic furnace by an air flow to be further decomposed, absorbing Hg with Au, and keeping Cd (cadmium) be in the sample; putting the processed sample into a cracking furnace to be further thermally decomposed, and vaporizing Cd and residual H in the sample at a high temperature; loading the vaporized Cd and residual Hg into a Cd atom trap by argon, selectively trapping the Cd by a tungsten filament, and absorbing the residual Hg by a Hg trap; and heating the tungsten filament or a molybdenum filament and gold amalgamation in the argon and hydrogen gas to release Cd and Hg, and carrying Cd and Hg into an atomic fluorescence spectrometer by the argon and the hydrogen. On the basis of realizing the function of simultaneously measuring Hg and Cd, the direct sample introduction type method and direct sample introduction type instrument for simultaneously measuring mercury and cadmium have the advantages that the structure of the entire measurement instrument is simplified so as to miniaturize the instrument, so that the instrument can conveniently meet the requirements of the conventional analysis and emergencies, and can be carried to the field by a vehicle. Moreover, the direct sample introduction type method and the direct sample introduction type instrument for simultaneously measuring mercury and cadmium have application prospect in the field detection.

Description

technical field [0001] The invention relates to heavy metal determination technology, in particular to a method and an instrument for direct sample injection without digestion and simultaneous determination of mercury and cadmium. Background technique [0002] With the development of industry, agriculture, and mining, more and more heavy metals pollute the living environment, daily necessities, food, and medicines, seriously polluting the environment and endangering human health. This is especially true for mercury (Hg) and cadmium (Cd), because they accumulate in the human body and animals and have carcinogenic, teratogenic and mutagenic effects. Therefore, the pollution caused by them has always been paid attention to, and the corresponding detection technology is also being developed by researchers. important areas. [0003] At present, detection techniques include ultraviolet-visible spectrophotometry, atomic absorption spectrometry, atomic fluorescence spectrometry, pl...

AI Technical Summary

Problems solved by technology

The commercial instruments for separate analysis of Hg and Cd are based on atomic absorption spectrometry (AAS) and atomic fluorescence spectrometry (AFS) as the ultimate detection means. Although both have high sensitivity, they cannot be realized.

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