A method for detecting heavy metal content in polymeric materials

Abstract

The invention relates to a method for detecting content of heavy metal in a polymeric material. The method includes the following steps: pretreating a sample, namely (1), adding a sufficient or excessive amount of concentrated sulfuric acid in a to-be-detected polymeric material sample, heating until sulfuric acid smoke is generated, and enabling the sample to be decomposed and carbonized; (2), adding a sufficient or excessive amount of concentrated nitric acid in the sample after being treated in the step (1) until carbide disappears and a solution is clear so as to enable the heavy metal to fully exist in the solution in a sulfate manner; (3), adding a sufficient or excessive amount of hydrochloric acid solution in the sample after being treated in the step (2), heating till boiling and maintaining reaction until the sulfate of the heavy metal is completely converted into corresponding chloride, cooling the chloride to obtain a to-be-detected sample solution, and then adopting a detection instrument to detect the content of the heavy metal in the to-be-detected sample solution. By the method, adsorption and volatilization loss of the heavy metal can be avoided, and detection results are high in accuracy; the method is supportive of large-scale operation and visual reaction phenomenon, and low in experiment cost.

Description

technical field

[0001] The invention relates to a method for detecting heavy metal content in polymeric materials by an open digestion method and a method for processing samples of the polymeric material, belonging to the technical field of heavy metal analysis and testing. Background technique

[0002] Polymer material is a kind of high molecular polymer, which refers to the general term of high molecular material formed by polymerization reaction of small molecular compounds. Due to its unique properties, it is widely used in consumer electronics, toys, tools, daily necessities, etc. In the manufacture of plastics, it has become a medium that people frequently come into contact with every day, and polymeric materials that may contain heavy metals such as Pb, Hg, Cd, and Cr have also become potential hidden dangers that threaten human health. After the product is discarded, it is more likely to cause soil, air, water pollution and other pollution, and further affect human h...

Examples

Embodiment 1

[0062] The sample of polymeric material containing heavy metals lead, cadmium, chromium and mercury described in this embodiment, select ERM-EC681k as "blind sample" for detection, the detection method of heavy metal lead, cadmium, chromium and mercury content in the polymeric material, Specifically include the following steps:

[0063] a. Pretreatment of the sample, specifically including the following steps:

[0064] (1) Weigh 0.3g of ERM-EC681k into a beaker, add 5mL of concentrated sulfuric acid with a mass concentration of 98%, place the beaker on a heating plate, and heat it to 350°C to emit sulfuric acid fumes. All the heavy metals contained will generate their corresponding sulfates, and the organic components will be completely carbonized into black substances;

[0065] (2) Add concentrated nitric acid with a mass concentration of 68% dropwise to the sample that has been carbonized in step (1) and emits sulfuric acid fumes until the black carbonized substance disappe...

Embodiment 2

[0074] The polymeric material sample containing lead, cadmium, chromium, and mercury described in this embodiment, selects ERM-EC680k as a "blind sample" for detection, and the detection method for the content of lead, cadmium, chromium, and mercury in the polymeric material specifically includes the following step:

[0075] a. Pretreatment of the sample, specifically including the following steps:

[0076] (1) Weigh 0.5g of ERM-EC680k into a beaker, add 5mL of concentrated sulfuric acid with a mass concentration of 98%, place the beaker on a heating plate, and heat it to 350°C to emit sulfuric acid fumes. All the heavy metals contained will generate their corresponding sulfates, and the organic components will be completely carbonized into black substances;

[0077] (2) Add concentrated nitric acid with a mass concentration of 65% dropwise to the sample that has been carbonized in step (1) and emits sulfuric acid fumes until the black carbonized substance disappears complete...

Embodiment 3

[0084] The sample of the polymeric material containing lead, cadmium, chromium and mercury described in this embodiment, selects BW3079 as a "blind sample" for detection. The detection method for the content of lead, cadmium, chromium and mercury in the polymeric material specifically includes the following steps:

[0085] a. Pretreatment of the sample, specifically including the following steps:

[0086] (1) Weigh 0.2g of BW3079 into a beaker, add 3mL of concentrated sulfuric acid with a mass concentration of 95%, place the beaker on a heating plate, heat to 300°C and emit sulfuric acid fumes, the sample is decomposed and carbonized, so that the heavy metal contained in the polymer material All generate their corresponding sulfates, and the organic components in them are completely carbonized into black substances;

[0087] (2) Add concentrated nitric acid with a mass concentration of 68% dropwise to the sample that has been carbonized in step (1) and emits sulfuric acid fume...

technical field

[0001] The invention relates to a method for detecting heavy metal content in polymeric materials by an open digestion method and a method for processing samples of the polymeric material, belonging to the technical field of heavy metal analysis and testing. Background technique

[0002] Polymer material is a kind of high molecular polymer, which refers to the general term of high molecular material formed by polymerization reaction of small molecular compounds. Due to its unique properties, it is widely used in consumer electronics, toys, tools, daily necessities, etc. In the manufacture of plastics, it has become a medium that people frequently come into contact with every day, and polymeric materials that may contain heavy metals such as Pb, Hg, Cd, and Cr have also become potential hidden dangers that threaten human health. After the product is discarded, it is more likely to cause soil, air, water pollution and other pollution, and further affect human h...

Examples

Embodiment 1

[0062] The sample of polymeric material containing heavy metals lead, cadmium, chromium and mercury described in this embodiment, select ERM-EC681k as "blind sample" for detection, the detection method of heavy metal lead, cadmium, chromium and mercury content in the polymeric material, Specifically include the following steps:

[0063] a. Pretreatment of the sample, specifically including the following steps:

[0064] (1) Weigh 0.3g of ERM-EC681k into a beaker, add 5mL of concentrated sulfuric acid with a mass concentration of 98%, place the beaker on a heating plate, and heat it to 350°C to emit sulfuric acid fumes. All the heavy metals contained will generate their corresponding sulfates, and the organic components will be completely carbonized into black substances;

[0065] (2) Add concentrated nitric acid with a mass concentration of 68% dropwise to the sample that has been carbonized in step (1) and emits sulfuric acid fumes until the black carbonized substance disappe...

Embodiment 2

[0074] The polymeric material sample containing lead, cadmium, chromium, and mercury described in this embodiment, selects ERM-EC680k as a "blind sample" for detection, and the detection method for the content of lead, cadmium, chromium, and mercury in the polymeric material specifically includes the following step:

[0075] a. Pretreatment of the sample, specifically including the following steps:

[0076] (1) Weigh 0.5g of ERM-EC680k into a beaker, add 5mL of concentrated sulfuric acid with a mass concentration of 98%, place the beaker on a heating plate, and heat it to 350°C to emit sulfuric acid fumes. All the heavy metals contained will generate their corresponding sulfates, and the organic components will be completely carbonized into black substances;

[0077] (2) Add concentrated nitric acid with a mass concentration of 65% dropwise to the sample that has been carbonized in step (1) and emits sulfuric acid fumes until the black carbonized substance disappears complete...

Embodiment 3

[0084] The sample of the polymeric material containing lead, cadmium, chromium and mercury described in this embodiment, selects BW3079 as a "blind sample" for detection. The detection method for the content of lead, cadmium, chromium and mercury in the polymeric material specifically includes the following steps:

[0085] a. Pretreatment of the sample, specifically including the following steps:

[0086] (1) Weigh 0.2g of BW3079 into a beaker, add 3mL of concentrated sulfuric acid with a mass concentration of 95%, place the beaker on a heating plate, heat to 300°C and emit sulfuric acid fumes, the sample is decomposed and carbonized, so that the heavy metal contained in the polymer material All generate their corresponding sulfates, and the organic components in them are completely carbonized into black substances;

[0087] (2) Add concentrated nitric acid with a mass concentration of 68% dropwise to the sample that has been carbonized in step (1) and emits sulfuric acid fume...

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