Micro-plastic quantification method
By combining ultraviolet irradiation and copper complex adsorption with electrified fiber bundles, the problem of quantification of microplastics in water was solved, and efficient and low-cost microplastic detection was achieved with an error of less than 5%.
Patent Information
- Application Number
- CN202510827345.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-19
- Publication Date
- 2025-10-21
AI Technical Summary
Existing technologies make it difficult to efficiently and accurately detect and quantify the content of microplastics in water, especially when treating wastewater containing trace amounts of microplastics, as there are limitations in detection efficiency and accuracy.
The concentrated microplastic solution was irradiated with ultraviolet light to generate more active functional groups, and then a copper complex solution was added. The copper ions were adsorbed using an energized fiber bundle. The microplastic concentration was obtained by weighing and simple calculation, and the copper ion content was determined by combining UV-visible spectrophotometry.
It achieves efficient and accurate quantification of microplastics in water, reduces detection costs, does not require complex operations and expensive instruments and equipment, and has an error of less than 5%.
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of pollutant detection, and in particular to a microplastic quantification method. Background Art
[0002] Microplastics are plastic particles smaller than 5 mm in diameter found in the environment. They can be formed by the gradual fragmentation of larger pieces of plastic, or they can be tiny particles from the moment they are manufactured. Due to their tiny size, microplastics are easily ingested by organisms and subsequently enter the food chain, posing a potential threat to ecosystems and human health. Studies have found that frequent use of single-use plastic products increases the risk of heart failure by 13%. Animal studies in mice have also shown that long-term use of plastic products increases myocardial damage and inflammation.
[0003] Microplastics are difficult to detect and remove due to their small size and relatively stable properties. Common methods for detecting microplastics in water include microscopic observation, spectral analysis, and staining with special chemical reagents. However, these methods have limitations in detection efficiency and accuracy, especially when dealing with wastewater containing trace amounts of microplastics. Therefore, accurate and efficient detection of microplastic content in wastewater is of great significance for assessing the degree of environmental pollution and formulating environmental protection strategies. Summary of the Invention
[0004] To address the difficulty in detecting and quantifying microplastics in water, the present invention provides a microplastic quantification method, comprising the following steps: 1. Accurately weigh a certain amount of the solution to be tested, heat it, and slowly concentrate it to the required volume. Seal the concentrate in a glass container and irradiate it with ultraviolet light. 2. Accurately prepare a copper complex solution of a certain concentration. According to the approximate content of microplastics in the concentrate in step 1, take an excess of the copper complex solution and add it to the concentrate. Stir slowly under heating and set aside. 3. Distribute the copper wire evenly in the fine-denier fiber bundle, cut the fiber bundle into a certain length, fix the two ends, and accurately weigh the mass of the fixed fiber bundle; 4. Connect the fiber bundle weighed in step 3 to the negative electrode of the original battery, and the solution in step 2 to the positive electrode of the original battery. Slowly stir the fiber bundle in the solution until the color of the solution no longer changes; 5. Slowly dry the fiber bundle after adsorption in step 4, subtract the mass weighed in step 3 from the weight, calculate the weight adsorbed by the fiber bundle, use UV-visible spectrophotometry to determine the content of copper ions in the solution in step 4, calculate the weight of copper ions adsorbed by the fiber bundle, and subtract the weight of the adsorbed copper ions from the weight of the fiber bundle to obtain the weight of microplastics adsorbed by the fiber bundle, and the concentration of microplastics in the tested solution can be calculated.
[0005] The smaller the volume of microplastics, the more functional groups are exposed on the surface. Under the action of ultraviolet rays and microorganisms, active functional groups such as hydroxyl, carboxyl, and amino groups are generated. The present invention uses ultraviolet rays to irradiate concentrated microplastics to oxidize more active functional groups on the surface of the microplastics, and then adds an excess of copper complex to the concentrated solution. The released copper ions will complex with the microplastics after ultraviolet irradiation, and finally will be adsorbed by the electrified fiber bundles. The content of microplastics in the water can be accurately obtained by calculation.
[0006] The present microplastic quantification method does not require complex and precise manipulations or chemical reactions; instead, it can determine the concentration of trace gold ions in wastewater through weighing and simple calculations. Furthermore, the method is simple to operate and does not require expensive instrumentation or complex pretreatment steps, significantly reducing testing costs.
[0007] Furthermore, in step 1 of the present method, the ultraviolet irradiation intensity is 90-120 μW / cm², and the irradiation time is 1-3 hours; the copper complex is an EDTA-copper ammonia complex or a copper-PAN complex. In step 3, the fine denier fiber is selected from one of PA, PP, or PET, with a specification of 3-10 denier, and the fiber bundle is 5-10 cm long and 0.3-1 cm in diameter. DETAILED DESCRIPTION
[0008] The present invention is described below with reference to examples, which are only used to explain the present invention and are not used to limit the scope of the present invention.
[0009] Example 1 A microplastic quantification method comprising the following steps: 1. Accurately weigh 10L of the test solution, heat it, and slowly concentrate it to 1L. Seal the concentrate in a glass container and irradiate it with 100μW / cm² ultraviolet light for 2 hours. 2. Accurately prepare a certain concentration of EDTA-copper ammonia complex solution. According to the approximate content of microplastics in the concentrate in step 1, take an excess of EDTA-copper ammonia complex solution and add it to the concentrate. Stir slowly under heating and set aside. 3. Distribute the copper wire evenly in an 8D fine-denier PA66 fiber bundle. Cut the fiber bundle into pieces with a length of 7 cm and a diameter of 0.6 cm, then fix the two ends and accurately weigh the mass of the fixed fiber bundle. 4. Connect the fiber bundle weighed in step 3 to the negative electrode of the original battery, and the solution in step 2 to the positive electrode of the original battery. Slowly stir the fiber bundle in the solution until the color of the solution no longer changes; 5. Slowly dry the fiber bundle after adsorption in step 4, subtract the mass weighed in step 3 from the weight, calculate the weight adsorbed by the fiber bundle, use UV-visible spectrophotometry to determine the content of copper ions in the solution in step 4, calculate the weight of copper ions adsorbed by the fiber bundle, and subtract the weight of the adsorbed copper ions from the weight of the fiber bundle to obtain the weight of microplastics adsorbed by the fiber bundle, and the concentration of microplastics in the tested solution can be calculated.
[0010] The microplastic concentration measured using the method of Example 1 was 112 ppm, and the concentration measured using spectral analysis was 115 ppm, with an error of 2.68%.
[0011] Example 2 A microplastic quantification method comprising the following steps: 1. Accurately weigh 10L of the test solution, heat it, and slowly concentrate it to 1L. Seal the concentrate in a glass container and irradiate it with 120μW / cm² ultraviolet light for 1 hour. 2. Accurately prepare a copper-PAN complex solution of a certain concentration. Based on the approximate content of microplastics in the concentrate in step 1, take an excess of the copper-PAN complex solution and add it to the concentrate. Stir slowly under heating and set aside. 3. Disperse the copper wire evenly in a 10D fine denier PET fiber bundle. Cut the fiber bundle into pieces with a length of 10 cm and a diameter of 1 cm, then fix the two ends and accurately weigh the mass of the fixed fiber bundle. 4. Connect the fiber bundle weighed in step 3 to the negative electrode of the original battery, and the solution in step 2 to the positive electrode of the original battery. Slowly stir the fiber bundle in the solution until the color of the solution no longer changes; 5. Slowly dry the fiber bundle after adsorption in step 4, subtract the mass weighed in step 3 from the weight, calculate the weight adsorbed by the fiber bundle, use UV-visible spectrophotometry to determine the content of copper ions in the solution in step 4, calculate the weight of copper ions adsorbed by the fiber bundle, and subtract the weight of the adsorbed copper ions from the weight of the fiber bundle to obtain the weight of microplastics adsorbed by the fiber bundle, and the concentration of microplastics in the tested solution can be calculated.
[0012] The microplastic concentration measured using the method of Example 2 was 120 ppm, and the concentration measured using spectral analysis was 115 ppm, with an error of 4.17%.
[0013] Example 3 A microplastic quantification method comprising the following steps: 1. Accurately weigh 10L of the test solution, heat it, and slowly concentrate it to 1L. Seal the concentrate in a glass container and irradiate it with 90μW / cm² ultraviolet light for 3 hours. 2. Accurately prepare a copper-PAN complex solution of a certain concentration. Based on the approximate content of microplastics in the concentrate in step 1, take an excess of the copper-PAN complex solution and add it to the concentrate. Stir slowly under heating and set aside. 3. Disperse the copper wire evenly in the 3D fine denier PP fiber bundle, cut the fiber bundle into 5 cm long and 0.3 cm in diameter, and fix the two ends. Accurately weigh the mass of the fixed fiber bundle; 4. Connect the fiber bundle weighed in step 3 to the negative electrode of the original battery, and the solution in step 2 to the positive electrode of the original battery. Slowly stir the fiber bundle in the solution until the color of the solution no longer changes; 5. Slowly dry the fiber bundle after adsorption in step 4, subtract the mass weighed in step 3 from the weight, calculate the weight adsorbed by the fiber bundle, use UV-visible spectrophotometry to determine the content of copper ions in the solution in step 4, calculate the weight of copper ions adsorbed by the fiber bundle, and subtract the weight of the adsorbed copper ions from the weight of the fiber bundle to obtain the weight of microplastics adsorbed by the fiber bundle, and the concentration of microplastics in the tested solution can be calculated.
[0014] The microplastic concentration measured using the method of Example 3 was 117 ppm, and the concentration measured using spectral analysis was 115 ppm, with an error of 1.71%.
[0015] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A microplastic quantification method, characterized in that: The following steps are involved:
1. Accurately weigh a certain amount of the solution to be tested, heat it, and slowly concentrate it to the required volume. Seal the concentrate in a glass container and irradiate it with ultraviolet light.
2. Accurately prepare a copper complex solution of a certain concentration. According to the approximate content of microplastics in the concentrate in step 1, take an excess of the copper complex solution and add it to the concentrate. Stir slowly under heating and set aside.
3. Evenly disperse the copper wire in the fine-denier fiber bundle, cut the fiber bundle into a certain length, fix the two ends, and accurately weigh the mass of the fixed fiber bundle; 4. Connect the fiber bundle weighed in step 3 to the negative electrode of the original battery, and the solution in step 2 to the positive electrode of the original battery. Slowly stir the fiber bundle in the solution until the color of the solution no longer changes; 5. Slowly dry the fiber bundle after adsorption in step 4, subtract the mass weighed in step 3 from the weight, calculate the weight adsorbed by the fiber bundle, use UV-visible spectrophotometry to determine the content of copper ions in the solution in step 4, calculate the weight of copper ions adsorbed by the fiber bundle, and subtract the weight of the adsorbed copper ions from the weight of the fiber bundle to obtain the weight of microplastics adsorbed by the fiber bundle, and the concentration of microplastics in the tested solution can be calculated.
2. The method according to claim 1, characterized in that In step 1, the UV irradiation intensity is 90~120μW / cm², and the irradiation time is 1~3h.
3. The method according to claim 1, characterized in that In step 2, the copper complex is an EDTA-copper ammonia complex or a copper-PAN complex.
4. The method according to claim 1, wherein In step 3, the fine denier fiber is selected from one of PA, PP or PET, and the specification is 3~10D.
5. The method according to claim 4, characterized in that The fiber bundle has a length of 5 to 10 cm and a diameter of 0.3 to 1 cm.