CN117782911A - Preparation method of simulated atmospheric particulate standard filter membrane for elemental analysis - Google Patents
Preparation method of simulated atmospheric particulate standard filter membrane for elemental analysis Download PDFInfo
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- CN117782911A CN117782911A CN202410014107.5A CN202410014107A CN117782911A CN 117782911 A CN117782911 A CN 117782911A CN 202410014107 A CN202410014107 A CN 202410014107A CN 117782911 A CN117782911 A CN 117782911A
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- 239000012528 membrane Substances 0.000 title claims abstract description 52
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- 238000000921 elemental analysis Methods 0.000 title claims description 13
- 238000000034 method Methods 0.000 claims abstract description 25
- 238000000967 suction filtration Methods 0.000 claims abstract description 21
- 238000001035 drying Methods 0.000 claims abstract description 14
- 238000005303 weighing Methods 0.000 claims abstract description 11
- 238000005259 measurement Methods 0.000 claims abstract description 9
- 238000012216 screening Methods 0.000 claims abstract description 8
- 239000007788 liquid Substances 0.000 claims abstract description 7
- 239000002270 dispersing agent Substances 0.000 claims abstract description 6
- 229920000049 Carbon (fiber) Polymers 0.000 claims abstract description 5
- 239000004917 carbon fiber Substances 0.000 claims abstract description 5
- 238000000227 grinding Methods 0.000 claims abstract description 5
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000002245 particle Substances 0.000 claims abstract description 5
- 238000001132 ultrasonic dispersion Methods 0.000 claims abstract description 5
- 239000012535 impurity Substances 0.000 claims abstract description 4
- 238000009736 wetting Methods 0.000 claims abstract description 4
- 239000006185 dispersion Substances 0.000 claims description 7
- 229910021642 ultra pure water Inorganic materials 0.000 claims description 7
- 239000012498 ultrapure water Substances 0.000 claims description 7
- 238000012795 verification Methods 0.000 claims description 6
- 239000002689 soil Substances 0.000 claims description 5
- 238000005406 washing Methods 0.000 claims description 5
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 3
- 229920004890 Triton X-100 Polymers 0.000 claims description 3
- 239000013504 Triton X-100 Substances 0.000 claims description 3
- 239000000428 dust Substances 0.000 claims description 3
- 238000004806 packaging method and process Methods 0.000 claims description 3
- 239000004417 polycarbonate Substances 0.000 claims description 3
- 229920000515 polycarbonate Polymers 0.000 claims description 3
- -1 polytetrafluoroethylene Polymers 0.000 claims description 3
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 3
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 3
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 3
- 239000000523 sample Substances 0.000 claims description 3
- GCLGEJMYGQKIIW-UHFFFAOYSA-H sodium hexametaphosphate Chemical compound [Na]OP1(=O)OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])O1 GCLGEJMYGQKIIW-UHFFFAOYSA-H 0.000 claims description 3
- 235000019982 sodium hexametaphosphate Nutrition 0.000 claims description 3
- 239000001577 tetrasodium phosphonato phosphate Substances 0.000 claims description 3
- 239000007864 aqueous solution Substances 0.000 claims 3
- 238000004458 analytical method Methods 0.000 abstract description 5
- 238000012360 testing method Methods 0.000 abstract description 5
- 238000007873 sieving Methods 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 3
- 238000003892 spreading Methods 0.000 abstract 1
- 239000000126 substance Substances 0.000 description 14
- 238000012544 monitoring process Methods 0.000 description 13
- 230000029087 digestion Effects 0.000 description 10
- 239000000243 solution Substances 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 238000001391 atomic fluorescence spectroscopy Methods 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 238000009616 inductively coupled plasma Methods 0.000 description 3
- 238000001095 inductively coupled plasma mass spectrometry Methods 0.000 description 3
- 238000003908 quality control method Methods 0.000 description 3
- 206010037660 Pyrexia Diseases 0.000 description 2
- 238000011088 calibration curve Methods 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000007865 diluting Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000002203 pretreatment Methods 0.000 description 2
- 238000004611 spectroscopical analysis Methods 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 238000009210 therapy by ultrasound Methods 0.000 description 2
- 238000004876 x-ray fluorescence Methods 0.000 description 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004993 emission spectroscopy Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000002354 inductively-coupled plasma atomic emission spectroscopy Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000000120 microwave digestion Methods 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000010561 standard procedure Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 238000004846 x-ray emission Methods 0.000 description 1
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Abstract
The invention relates to the technical field of atmospheric particle measurement, in particular to a preparation method of a standard filter membrane simulating atmospheric particles for element analysis, which comprises the steps of removing impurities from a target sample through primary screening, grinding, sieving, drying, accurately weighing the target sample in a centrifuge tube, adding a dispersing agent, performing ultrasonic dispersion, putting the filter membrane into a suction filtration system for wetting by using carbon fiber tweezers, performing suction filtration on the dispersed sample, fully shaking a dispersing liquid by hands before suction filtration, spreading and drying after suction filtration is completed, thereby realizing the preparation method of the standard filter membrane, providing assistance for a method for measuring various elements, and simultaneously ensuring good deviation, good uniformity, wide application, flexible preparation and other good effects through test measurement.
Description
Technical Field
The invention relates to the technical field of atmospheric particle measurement, in particular to a preparation method of a simulated atmospheric particle standard filter membrane for elemental analysis.
Background
The method has the advantages of well breaking pollution control and attack, strengthening multi-pollutant cooperative control and regional cooperative treatment, basically eliminating heavy pollution weather, and being a core task of atmospheric environment monitoring and treatment. In order to achieve the aim, the chemical component monitoring of the atmospheric particulate matters becomes one of important construction directions of an ecological environment monitoring system in the next stage, and an online monitoring method with high time resolution is combined with a high-density monitoring network to be used as a construction target of the chemical component monitoring system of the atmospheric particulate matters in China.
The environmental standards for measuring the inorganic elements of the atmospheric particulates mainly include five types, and the standard methods are divided into two types according to whether pretreatment such as digestion is needed or not, wherein one type is a method which needs to be subjected to pretreatment of digestion, and the method is also a more common analysis method in a laboratory, and comprises an inductively coupled plasma mass spectrometry (HJ 657-2013), an inductively coupled plasma emission spectrometry (HJ 777-2015), an atomic fluorescence spectrometry (HJ 1133-2020) and the like; the other type is an X-ray fluorescence spectrometry which is mainly used for on-line analysis without digestion pretreatment, and is respectively an energy dispersion type (HJ 829-2017) and a wavelength dispersion type (HJ 830-2017).
At present, the calibration and check of the monitoring method for the chemical components of the particulate matters are only aimed at chemical analysis instruments, one type is to measure the repeatability and the accuracy of the chemical analysis instruments by using standard substances in the form of solutions, and the other type is to calibrate the instruments by using filter membranes of high-purity metals or metal compounds, so as to establish a standard working curve. Compared with the U.S. and European standards, the full-flow calibration and verification covering the steps of sample collection and pretreatment cannot be realized due to the lack of standard substances which are real sample matrixes and are in the form of filter membranes. And the automatic monitoring equipment of the domestic inorganic elements is calibrated and checked mainly by means of quality control samples provided by manufacturers at present, and the magnitude traceability of the automatic monitoring equipment cannot be guaranteed.
Therefore, for the above reasons, a preparation method of a simulated atmospheric particulate standard filter membrane for elemental analysis needs to be designed, so that the quality control and metering requirements of a national atmospheric particulate chemical component monitoring network are met, and the accuracy and consistency of chemical component monitoring data are met.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides a preparation method of an atmospheric particulate standard simulation filter membrane for elemental analysis, which meets the quality control and metering requirements of a national atmospheric particulate chemical component monitoring network and meets the accuracy and consistency of chemical component monitoring data.
In order to achieve the above purpose, the invention provides a preparation method of a simulated atmospheric particulate standard filter membrane for elemental analysis, which comprises the following steps:
s1, primarily screening a target sample to remove impurities, grinding, screening and drying for later use;
s2, accurately weighing a target sample in a centrifuge tube by using an analytical balance calibrated by verification, adding a dispersing agent, and performing ultrasonic dispersion;
s3, placing the filter membrane into a suction filtration system by using carbon fiber tweezers for wetting, performing suction filtration on the dispersed sample, fully shaking the dispersion liquid by hands before suction filtration, and washing the inner walls of the centrifuge tube and the suction filtration funnel with a small amount of ultrapure water for many times after the sample is completely transferred, so that the sample is completely transferred onto the filter membrane;
s4, after suction filtration is completed, tiling and drying are carried out;
s5, placing the dried sample in a clean filter membrane sample box, numbering and packaging for later use.
The sample is a truly collected atmospheric particulate sample or soil or dust.
Sieving requires controlling the mesh size and standard mesh number to ensure that the size of the sieved particulate is no more than 100 microns.
The sample weighing amount in S2 is (0.01-0.1) g, and the sample weighing amount is controlled to be within 1+/-3% of the weighing value in batch preparation.
The dispersing agent in S2 is ultrapure water, triton X-100 water solution, sodium hexametaphosphate water solution and polyvinyl alcohol water solution, the volume of the dispersing liquid is (10-40) mL, and the dispersing time is (20-60) min.
And S3, the filter membrane with low background element content is a polytetrafluoroethylene hydrophilic filter membrane, a polycarbonate filter membrane or ashless filter paper.
The drying temperature in S4 is not higher than 50 ℃.
The standard value of the element content of the filter membrane is finally determined by the method of different principles and the combined measurement of a plurality of laboratories.
The beneficial technical effects of the invention are as follows:
after element measurement, the filter membrane prepared by the method has the relevant linear coefficients superior to 0.999, the deviation of the filter membrane is not more than 4%, and the uniformity is good, so that the filter membrane can be used for verification of accuracy of a digestion pretreatment method required by an inductively coupled plasma mass spectrometry (HJ 657-2013), an inductively coupled plasma fever spectrometry (HJ 777-2015), an atomic fluorescence spectrometry (HJ 1133-2020) and the like.
Meanwhile, the method can prepare standard filter membranes with different element contents, can prepare standard filter membranes with element concentration gradients, and is used for establishing a calibration curve of a measuring instrument in an X-ray fluorescence spectrum method (HJ 829-2017 and HJ 830-2017) and verifying the accuracy of the measuring method.
Drawings
FIG. 1 is a schematic diagram of the results of the uniformity test for sample A according to the present invention.
FIG. 2 is a graph showing the results of the uniformity test for sample B according to the present invention.
Detailed Description
Referring to fig. 1-2, the invention provides a preparation method of a simulated atmospheric particulate standard filter membrane for elemental analysis, which comprises the following steps:
s1, primarily screening a target sample to remove impurities, grinding, screening and drying for later use;
s2, accurately weighing a target sample in a centrifuge tube by using an analytical balance calibrated by verification, adding a dispersing agent, and performing ultrasonic dispersion;
s3, placing the filter membrane into a suction filtration system by using carbon fiber tweezers for wetting, performing suction filtration on the dispersed sample, fully shaking the dispersion liquid by hands before suction filtration, and washing the inner walls of the centrifuge tube and the suction filtration funnel with a small amount of ultrapure water for many times after the sample is completely transferred, so that the sample is completely transferred onto the filter membrane;
s4, after suction filtration is completed, tiling and drying are carried out;
s5, placing the dried sample in a clean filter membrane sample box, numbering and packaging for later use.
The target sample is an actually collected atmospheric particulate sample or soil or dust.
Sieving requires controlling the mesh size and standard mesh number to ensure that the size of the sieved particulate is no more than 100 microns.
The sample weighing amount in S2 is (0.01-0.1) g, and the sample weighing amount is controlled to be within 1+/-3% of the weighing value in batch preparation.
The agent separating liquid in S2 is ultrapure water, triton X-100 water solution, sodium hexametaphosphate water solution and polyvinyl alcohol water solution, the volume of the dispersion liquid is (10-40) mL, and the dispersing time is (20-60) min.
And S3, the filter membrane with low background element content is a polytetrafluoroethylene hydrophilic filter membrane, a polycarbonate filter membrane or ashless filter paper.
The drying temperature in S4 is not higher than 50 ℃. The standard value of the element content of the filter membrane is finally determined by the method of different principles and the combined measurement of a plurality of laboratories.
Examples:
the soil national standard substance after grinding, sieving (200 meshes), drying and the like is respectively prepared and weighed into 0.05g (sample A) and 0.07g (sample B) by an analytical balance (the sample is required to be kept to be accurate to 0.00001 g) and placed in a 50mL centrifuge tube.
After 40mL of ultrapure water is added, ultrasonic treatment is carried out for 40min, after ultrasonic treatment is finished, the mixture is transferred into a filtering system with ashless filter paper with the aperture of 20 microns for suction filtration, and a small amount of washing is carried out for many times to ensure that no residual soil sample exists in the centrifuge tube. Drying after the filtration is finished, and storing and numbering in a filter box.
Samples a and B in this example were each prepared in 300 pieces, and 12 pieces were randomly drawn from each sample for pretreatment and testing.
The element measuring method comprises the following steps:
step 1, carefully folding a filter membrane sample by using carbon fiber tweezers, putting the filter membrane sample into a quartz digestion tank, and adding 4mL of reverse aqua regia (HNO) 3 Hcl=3:1), and the lid is closed and left to stand until no bubbles emerge.
And 2, placing the digestion tank in a microwave digestion instrument, and running a digestion program (heating at 260 ℃ for 20min and maintaining at 260 ℃ for 60 min).
And 3, after digestion is finished, filtering and transferring the digestion solution into a centrifuge tube, washing with pure water for a plurality of times, diluting to about 50mL, accurately weighing the mass of the solution (accurate to 0.00001 g), and uniformly mixing with a vortex mixer to be measured.
Step 4, using 2% HNO for the standard substance of the 29 elements mixed solution of the nitric acid matrix 3 Gradually diluting to 0 mug/kg, 5 mug/kg, 10 mug/kg, 50 mug/kg, 100 mug/kg, 500 mug/kg, 1000 mug/kg, 1500 mug/kg, 3000 mug/kg, 5000 mug/kg and the like, and uniformly mixing by a vortex mixer to be measured.
And 5, measuring the content of each element by ICP-OES, wherein the measuring wavelength is divided into Al (396.152 nm), as (189.042 nm), be (313.042 nm), bi (223.061 nm), cd (228.802 nm), co (228.616 nm), cr (267.716 nm), fe (259.94 nm), ga (294.364 nm), mn (257.610 nm), ni (231.604 nm), pb (220.353 nm), V (309.311 nm) and Zn (213.856 nm), the measuring wavelength is divided into different concentration sections according to the concentration of a sample, the linear correlation coefficient is better than 0.999, and the unit of the measuring result is mug.
As shown in the sample measurement results of fig. 1 and 2, the relative standard deviation of the element content in the randomly chosen 12 films in the samples A and B with different element concentrations is not more than 4%, so that the filter film prepared by the method has good uniformity, and can be used for verification of accuracy of a digestion pretreatment method required by an inductively coupled plasma mass spectrometry (HJ 657-2013), an inductively coupled plasma fever spectrometry (HJ 777-2015), an atomic fluorescence spectrometry (HJ 1133-2020) and the like.
In addition, the method can prepare standard filter membranes with different element contents, can prepare standard filter membranes with element concentration gradients, and is used for establishing a calibration curve of a measuring instrument in an X-ray fluorescence spectrum method (HJ 829-2017 and HJ 830-2017) and verifying the accuracy of the measuring method.
The above is only a preferred embodiment of the present invention, only for helping to understand the method and the core idea of the present application, and the protection scope of the present invention is not limited to the above examples, and all technical solutions belonging to the concept of the present invention belong to the protection scope of the present invention. It should be noted that modifications and adaptations to the present invention may occur to one skilled in the art without departing from the principles of the present invention and are intended to be within the scope of the present invention.
The invention fundamentally solves the problems that the prior art lacks standard substances in the form of a filter membrane compared with foreign standards, and cannot realize the whole-flow calibration and check covering the links of sample collection and pretreatment, and realizes the preparation method of the standard filter membrane through the steps of dispersing samples, completely carrying out suction filtration, tiling, drying and the like, thereby providing help for the method for measuring various elements, and simultaneously ensuring the good effects of small deviation, good uniformity, wide application, flexible preparation and the like through test measurement.
Claims (6)
1. The preparation method of the simulated atmospheric particulate standard filter membrane for elemental analysis is characterized by comprising the following steps of:
s1, primarily screening a target sample to remove impurities, grinding, screening and drying for later use, wherein the screening requires controlling the size of a screen hole and the standard mesh number, and the size of screened particles is ensured not to exceed 100 microns;
s2, accurately weighing a target sample in a centrifuge tube by using an analytical balance after verification and calibration, adding a dispersing agent, and performing ultrasonic dispersion, wherein the ultrasonic dispersion time is 40min;
s3, placing the filter membrane into a suction filtration system by using carbon fiber tweezers for wetting, performing suction filtration on the dispersed sample, fully shaking the dispersion liquid by hands before suction filtration, and washing the inner walls of the centrifuge tube and the suction filtration funnel with a small amount of ultrapure water for many times after the sample is completely transferred, so that the sample is completely transferred onto the filter membrane;
s4, after suction filtration is completed, tiling and drying are carried out, wherein the drying temperature is not higher than 50 ℃;
s5, placing the dried sample in a clean filter membrane sample box, numbering and packaging for later use.
2. The method for preparing a simulated atmospheric particulate standard filter membrane for elemental analysis according to claim 1, wherein said sample is a truly collected atmospheric particulate sample or soil or dust.
3. The method for preparing a simulated atmospheric particulate standard filter membrane for elemental analysis according to claim 1, wherein the sample weight in S2 is 0.01g to 0.1g, and the sample weight is controlled to be within 1±3% of the weight value in mass preparation.
4. The method for preparing a simulated atmospheric particulate standard filter membrane for elemental analysis according to claim 1, wherein the dispersant in S2 is ultrapure water, a triton X-100 aqueous solution, a sodium hexametaphosphate aqueous solution, a polyvinyl alcohol aqueous solution, the volume of the dispersion is 10mL to 40mL, and the dispersing time is 20min to 60min.
5. The method for preparing the simulated atmospheric particulate standard filter membrane for elemental analysis according to claim 1, wherein the filter membrane in S3 is a filter membrane with low background element content, and the filter membrane is a polytetrafluoroethylene hydrophilic filter membrane, a polycarbonate filter membrane or an ashless filter paper.
6. The method for preparing the standard filter membrane simulating the atmospheric particulates for elemental analysis according to claim 1, wherein the standard value of the element content of the filter membrane is finally determined by a method of different principles and combined measurement of a plurality of laboratories.
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| CN202410014107.5A CN117782911A (en) | 2024-01-04 | 2024-01-04 | Preparation method of simulated atmospheric particulate standard filter membrane for elemental analysis |
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| CN202410014107.5A CN117782911A (en) | 2024-01-04 | 2024-01-04 | Preparation method of simulated atmospheric particulate standard filter membrane for elemental analysis |
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