A method for the determination of dioxins in sediments and a rapid pretreatment method for sediments

Abstract

The invention provides a precipitate rapid pretreatment method, and a dioxin measuring method. The precipitate rapid pretreatment method comprises following steps: sample extraction; sample purification; and nitrogen blow concentration. According to the precipitate rapid pretreatment method and the dioxin measuring method, the performance of adopted silver ion-modified amino silica gel is excellent;, problems of common silver nitrate silica gel that silver ion stability is poor, and falling of silver ions is easily caused are solved; one-step process is adopted for sample purification, the pertinence of the filling sequence of filling materials in one-step silica gel column is high, filling sequence is reasonable, complex matrix effect is avoided, a plurality of impurities in dioxin organic pollutants are removed, and influences on subsequent detection on dioxin compounds are avoided; and above all, it is shown by experiments that detection result accuracy and reproducibility of the precipitate rapid pretreatment method and the dioxin measuring method is high, and recovery rate is high.

Description

technical field [0001] The invention relates to the technical field of pollutant monitoring, in particular to a method for measuring dioxins in sediments and a rapid pretreatment method for sediments. Background technique [0002] The environmental toxicity of dioxin-like substances has been widely concerned by people all over the world. At present, there are more and more types of organic pollutants in the environment, such as dioxins, and the matrix in which such organic pollutants are located is also very complex. The matrix often contains various acidic compounds, basic compounds, aromatic compounds, Containing impurities such as sulfides and hydrated compounds, if these impurities are not treated, they will cause great interference to the detection results of subsequent organic pollutants and affect the detection results. At present, the quantitative detection of dioxins in the environment is a difficult point in the field of organic ultra-trace analysis. For environme...

AI Technical Summary

Problems solved by technology

At present, there are more and more types of organic pollutants in the environment, such as dioxins, and the matrix in which such organic pollutants are located is also very complex. The matrix often contains various acidic compounds, basic compounds, aromatic compounds, Contains impurities such as sulfides and hydrated compounds. If these impurities are not treated, they will greatly interfere with the detection results of subsequent organic pollutants and affect the detection results.

At present, the quantitative detection of dioxins in the environment is a difficult point in the field of organic ultra-trace analysis. For environmental samples, liquid-liquid extraction is often used to extract samples at home and abroad, and the purification process refers to the US EPA method for multi-stage column purification. ,, but there are the following disadvantages: the entire purification process is long, the steps are cumbersome, it takes a long time (about three to four days), the purification method is complicated, the requirements for analysts are high, and the requirements for laboratory conditions are high.

The above problems limit the rapid development of dioxin detection

[0003] Moreover, silica gel is a kind of good adsorption. Although the silica gel chromatography column prepared by the ordinary silica gel chromatography column preparation method can remove some impurities in the matrix, when the matrix is ​​complicated and the dioxin organic pollutants in the matrix are detected, the ordinary silica gel chromatography column is used. The silica gel column prepared by the silica gel chromatography column preparation method is difficult to remove various acidic compounds, basic compounds, aromatic compounds, sulfide-containing compounds and water-containing compounds in the matrix. The interference to the subsequent detection of dioxins is still It is very large and directly affects the final test result

Therefore, silica gel chromatographic columns prepared by common silica gel chromatographic column preparation methods cannot be used to detect dioxin organic pollutants in complex matrices

Images