ICP-MS-Based Method for Detecting Heavy Metal Content in Textiles

Abstract

The present invention provides a method for detecting heavy metal content in textiles based on ICP-MS. This technical solution improves the sample pretreatment method and adopts a brand-new detection mode. Specifically, the present invention first mixes the pulverized test materials with a high molecular polymer and adds magnesium chloride to dissolve heavy metal salts in the system; on this basis, methods such as ultrasonic oscillation and decompression extraction are used to promote the dissolution of heavy metals, laying a foundation for the subsequent digestion step; subsequently, the present invention uses a mixed solution containing potassium dichromate, calcium hypochlorite, and sodium carbonate to perform a digestion reaction, fully removing organic substances and reducing substances in the test materials, thereby reducing the influence of impurities on mass spectrometry detection; during the mass spectrometry detection process, the present invention uses neon as the carrier gas and defines specific detection modes, flow rates, atomization temperatures and other conditions, thereby optimizing the detection effect. The operation of the present invention is simple, with higher accuracy and sensitivity, and has prominent technical advantages.

Description

Technical Field

[0001] The invention relates to the technical field of analytical chemistry, and in particular to a method for detecting heavy metal content in textiles based on ICP-MS. Background Art

[0002] Heavy metals usually refer to metals with a density of 5.0 g / cm 3 The above metals, such as lead, mercury, copper, zinc, chromium, etc. As we all know, some heavy metals are essential trace elements for the human body, but their high concentrations will cause harm to the human body.

[0003] The sources of heavy metals in textiles are relatively complex. Heavy metals may be introduced at any stage of the raw materials, production and use of textiles. Most of them come from the later processing, such as various metal complexes, mordant dyes, phthalocyanine structure dyes, fixing agents, catalysts, flame retardants, finishing agents, etc., as well as various metal complexes used for softening hard water, desizing and refining, bleaching, printing and other processes. For natural fiber fabrics, heavy metals may come from environmental pollution, such as heavy metals such as lead, cadmium, mercury, and arsenic in the growth process of plant fibers, which pollute natural fibers through environmental migration and biological enrichment. For natural fiber fabrics, heavy metals may come from environmental pollution, such as heavy metals such as lead, cadmium, mercury, and arsenic in the growth process of plant fibers, which pollute natural fibers through environmental migration and biological enrichment.

[0004] Excessive intake of heavy metals can seriously harm human health. Excessive intake of mercury can cause hematuria, insomnia, mental disorders, and even life-threatening in severe cases; cadmium can cause acute pneumonia and pulmonary fibrosis; antimony can damage the liver and heart, cause anaphylactic shock, and even life-threatening in severe cases. Heavy metals are seriously harmful to the human body. They may damage human tissue cells, cause thinning of human bones, and chronic poisoning; they may damage the structure of human proteins, causing various side effects that endanger health; they may cause muscle paralysis, developmental arrest, and low fertility; and the random discharge of heavy metals accumulates in nature and may re-enter the human body through the food chain. Since various diseases caused by heavy metals have various symptoms, it is difficult to identify the cause and the symptoms will last for a long time. Therefore, the determination of heavy metal content is crucial in the quality inspection of textiles.

[0005] In the prior art, the methods used to detect heavy metal content in textiles mainly include ICP-AES, AAS, PFS, colorimetry, etc. The above methods generally have defects such as cumbersome operation and low accuracy, which is not conducive to ensuring the detection efficiency of products. Summary of the invention

[0006] The present invention aims at the technical defects of the prior art and provides a method for detecting heavy metal content in textiles based on ICP-MS to solve the technical problems of cumbersome operation and low accuracy of conventional detection methods.

[0007] To achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] The method for detecting heavy metal content in textiles based on ICP-MS includes the following steps:

[0009] 1) Take the textile sample to be tested, crush it to a particle size less than 0.5 mm, add epoxy resin to it, and then add magnesium chloride solution to the container. The volume percentage of the magnesium chloride solution is 15%, perform ultrasonic oscillation treatment for 20 min, and then perform reduced pressure extraction for 15 min under the conditions of 50 °C and 0.6 atmospheric pressure. The mass ratio of the epoxy resin to the magnesium chloride solution is 3:7; then centrifuge at a speed not higher than 4000 rpm and take the liquid phase;

[0010] 2) Prepare a mixed solution containing potassium dichromate, calcium hypochlorite, and sodium carbonate, add it to the product obtained in step 1), mix well, heat up to 80 °C within 10 min, keep it for 20 min, then heat up to 120 °C within 5 min, and pressurize to 2 atmospheric pressures, keep it for 20 min, then heat up to 180 °C within 10 min, further pressurize to 3.5 atmospheric pressures, keep it for 15 min, and return to normal pressure and naturally cool to room temperature;

[0011] 3) Take the product obtained in step 2) and enter it into the ICP-MS instrument through an injector, atomize it, mix it with neon gas, then mix it with atomized acetonitrile and methanol, and then introduce it into the plasma flame for detection in STD mode. Use helium as the collision reaction gas, the radio frequency power is 1.6 - 1.8 kW, the flow rate is 8.8 - 9.6 mL / min, and the atomization temperature is 22 - 26 °C.

[0012] Preferably, in step 1), the particle size of the sample is crushed to 0.1 - 0.2 mm.

[0013] Preferably, in step 1), the final concentration of the epoxy resin is 0.2 mol / L.

[0014] Preferably, in step 1), the final concentration of the magnesium chloride solution is 0.05 g / mL.

[0015] Preferably, in step 1), the frequency of the ultrasonic oscillation is 28 KHz.

[0016] Preferably, in step 1), the centrifugation speed is 3500 rpm and the centrifugation time is 8 min.

[0017] Preferably, in step 2), the molar ratio of potassium dichromate, calcium hypochlorite, and sodium carbonate is 1:2:2.3.

[0018] Preferably, the duration of natural cooling to room temperature is not more than 30 min.

[0019] Preferably, in step 3), the molar ratio of acetonitrile to methanol is 1:2.

[0020] Preferably, in step 3), the radio frequency power is 1.7 kW, the flow rate is 9.2 mL / min, the atomization temperature is 24 °C, and the residence time is 0.22 s.

[0021] The present invention provides a method for detecting heavy metal content in textiles based on ICP-MS. This technical solution improves the sample pretreatment method and adopts a new detection mode, thereby improving the detection accuracy. Specifically, the present invention first mixes the pulverized test material with a high molecular polymer and adds magnesium chloride to dissolve the heavy metal salts in the system; on this basis, ultrasonic oscillation, decompression extraction and other methods are used to promote the dissolution of heavy metals, laying a foundation for the subsequent digestion step; subsequently, the present invention uses a mixed solution containing potassium dichromate, calcium hypochlorite, and sodium carbonate to perform a digestion reaction to fully remove organic substances and reducing substances in the test material, thereby reducing the influence of impurities on mass spectrometry detection; during the mass spectrometry detection process, the present invention uses neon as the carrier gas and defines specific detection modes, flow rates, atomization temperatures and other conditions, thereby optimizing the detection effect. The operation of the present invention is simple, with higher accuracy and sensitivity, and has prominent technical advantages. Detailed Embodiments

[0022] The following will describe the detailed embodiments of the present invention in detail. To avoid excessive unnecessary details, well-known structures or functions will not be described in detail in the following embodiments. Approximating language used in the following embodiments may be used for quantitative descriptions, indicating that certain variations in quantity are permissible without changing the basic function. Unless otherwise defined, the technical and scientific terms used in the following embodiments have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0023] Example 1

[0024] A method for detecting heavy metal content in textiles based on ICP-MS, comprising the following steps:

[0025] 1) Take the textile sample to be tested, crush it to a particle size less than 0.5 mm, add epoxy resin to it, then add magnesium chloride solution to the container. The volume percentage of the magnesium chloride solution is 15%, perform ultrasonic oscillation treatment for 20 min, then perform reduced-pressure extraction at 50 °C and 0.6 atmospheric pressure for 15 min. The mass ratio of the epoxy resin to the magnesium chloride solution is 3:7; then centrifuge at a speed not higher than 4000 rpm and take the liquid phase;

[0026] 2) Prepare a mixed solution containing potassium dichromate, calcium hypochlorite, and sodium carbonate, add it to the product obtained in step 1), mix well, heat it to 80 °C within 10 min, hold for 20 min, then heat it to 120 °C within 5 min and pressurize to 2 atmospheric pressures, hold for 20 min, then heat it to 180 °C within 10 min and further pressurize to 3.5 atmospheric pressures, hold for 15 min, restore to normal pressure and naturally cool to room temperature;

[0027] 3) Take the product obtained in step 2) and enter it into an ICP-MS instrument through an injector, atomize it and mix it with neon gas, then mix it with atomized acetonitrile and methanol, and then introduce it into the plasma flame, and perform detection in STD mode. Use helium as the collision reaction gas, the radio frequency power is 1.6 - 1.8 kW, the flow rate is 8.8 - 9.6 mL / min, and the atomization temperature is 22 - 26 °C.

[0028] Example 2

[0029] The method for detecting heavy metal content in textiles based on ICP-MS includes the following steps:

[0030] 1) Take the textile sample to be tested, crush it to a particle size less than 0.5 mm, add epoxy resin to it, then add magnesium chloride solution to the container. The volume percentage of the magnesium chloride solution is 15%, perform ultrasonic oscillation treatment for 20 min, then perform reduced-pressure extraction at 50 °C and 0.6 atmospheric pressure for 15 min. The mass ratio of the epoxy resin to the magnesium chloride solution is 3:7; then centrifuge at a speed not higher than 4000 rpm and take the liquid phase;

[0031] 2) Prepare a mixed solution containing potassium dichromate, calcium hypochlorite, and sodium carbonate, add it to the product obtained in step 1), mix well, heat it to 80 °C within 10 min, hold for 20 min, then heat it to 120 °C within 5 min and pressurize to 2 atmospheric pressures, hold for 20 min, then heat it to 180 °C within 10 min and further pressurize to 3.5 atmospheric pressures, hold for 15 min, restore to normal pressure and naturally cool to room temperature;

[0032] 3) The product obtained in step 2) is introduced into the ICP-MS instrument through an injector, atomized and mixed with neon gas, then mixed with atomized acetonitrile and methanol, and then introduced into the plasma flame for detection in STD mode. Helium gas is used as the collision reaction gas, the radio frequency power is 1.6 - 1.8 kW, the flow rate is 8.8 - 9.6 mL / min, and the atomization temperature is 22 - 26 °C. Among them, the particle size of the sample in step 1) is crushed to 0.1 - 0.2 mm. The final concentration of the epoxy resin in step 1) is 0.2 mol / L. The final concentration of the magnesium chloride solution in step 1) is 0.05 g / mL. The frequency of the ultrasonic oscillation in step 1) is 28 KHz. The rotation speed of centrifugation in step 1) is 3500 rpm, and the duration of centrifugation is 8 min. In step 2), the molar ratio of potassium dichromate, calcium hypochlorite, and sodium carbonate is 1∶2∶2.3. The duration of natural cooling to room temperature is not higher than 30 min. In step 3), the molar ratio of acetonitrile and methanol is 1∶2. In step 3), the radio frequency power is 1.7 kW, the flow rate is 9.2 mL / min, the atomization temperature is 24 °C, and the residence time is 0.22 s.

[0033] The above has described the embodiments of the present invention in detail, but the content described is only the preferred embodiments of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the scope of the application of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for detecting the heavy metal content in textiles based on ICP-MS, characterized in that It includes the following steps: 1) Take the textile sample to be tested, crush it to a particle size less than 0.5 mm, add epoxy resin to it, then add magnesium chloride solution to the container. The volume percentage of the magnesium chloride solution is 15%, perform ultrasonic oscillation treatment for 20 min, then carry out reduced pressure extraction for 15 min under the conditions of 50 °C and 0.6 atmospheric pressure. The mass ratio of the epoxy resin to the magnesium chloride solution is 3:7; then centrifuge at a speed not higher than 4000 rpm and take the liquid phase; 2) Prepare a mixed solution containing potassium dichromate, calcium hypochlorite, and sodium carbonate, add it to the product obtained in step 1), mix well, heat up to 80 °C within 10 min, keep it for 20 min, then heat up to 120 °C within 5 min, and pressurize to 2 atmospheric pressures, keep it for 20 min, then heat up to 180 °C within 10 min, further pressurize to 3.5 atmospheric pressures, keep it for 15 min, restore to normal pressure and naturally cool to room temperature; 3) Take the product obtained in step 2) and enter it into an ICP-MS instrument through an injector, mix it with neon gas after atomization, then mix it with atomized acetonitrile and methanol, and then introduce it into the plasma flame, and perform detection in STD mode. Use helium as the collision reaction gas, the radio frequency power is 1.6 - 1.8 kW, the flow rate is 8.8 - 9.6 mL / min, and the atomization temperature is 22 - 26 °C.

2. The method for detecting the heavy metal content in textiles based on ICP-MS according to claim 1, wherein In step 1), the particle size of the sample is crushed to 0.1 - 0.2 mm.

3. The method for detecting the heavy metal content in textiles based on ICP-MS according to claim 1, wherein, In step 1), the final concentration of the epoxy resin is 0.2 mol / L.

4. The method for detecting heavy metal content in textiles based on ICP-MS according to claim 1, wherein In step 1), the final concentration of the magnesium chloride solution is 0.05 g / mL.

5. The method for detecting heavy metal content in textiles based on ICP-MS according to claim 1, wherein, In step 1), the frequency of the ultrasonic oscillation is 28 KHz.

6. The method for detecting the heavy metal content of textiles based on ICP-MS according to claim 1, wherein In step 1), the centrifugation speed is 3500 rpm and the centrifugation time is 8 min.

7. The method for detecting heavy metal content in textiles based on ICP-MS according to claim 1, characterized in that, In step 2), the molar ratio of potassium dichromate, calcium hypochlorite, and sodium carbonate is 1:2:2.

3.

8. The method for detecting heavy metal content in textiles based on ICP-MS according to claim 1, characterized in that, The time for natural cooling to room temperature is not higher than 30 min.

9. The method for detecting heavy metal content in textiles based on ICP-MS according to claim 1, wherein, In step 3), the molar ratio of acetonitrile to methanol is 1:

2.

10. The method for detecting heavy metal content in textiles based on ICP-MS according to claim 1, wherein, In step 3), the radio frequency power is 1.7 kW, the flow rate is 9.2 mL / min, the atomization temperature is 24 °C, and the residence time is 0.22 s.