Aromatic amine extraction method, aromatic amine detection method, aromatic amine hollow fiber membrane extraction device and aromatic amine hollow fiber membrane detection equipment

Abstract

The invention relates to an organic substance treatment method, and particularly discloses an aromatic amine extraction method, a detection method, a hollow fiber membrane extraction device and detection equipment. The extraction method comprises the following steps: S1, adjusting the pH value of a sample solution to be extracted to 5-7, and respectively putting the sample solution and an extraction agent into a solution taking container; s2, transmitting an extracting agent to the receiving chamber and completing filling; s3, the sample liquid is conveyed into the working chamber and circularly flows in one direction, the sample liquid is kept to flow outside the hollow fiber membrane during the period, the circulation rate of the sample liquid is controlled to be 0.1-5 mL / min, and the extraction lasting time is 20-60 min. According to the aromatic amine extraction method provided by the invention, a dynamic extraction process is introduced, so that the extraction efficiency is greatly improved, and compared with an original static extraction process, the use variety and consumption of chemical agents are reduced, and the influence on the environment and the health of operators is reduced while the cost is reduced.

Description

Technical Field

[0001] This invention relates to methods for treating organic matter, specifically to extraction methods for organic matter, methods for detecting the content of organic matter used in conjunction with extraction methods, and extraction apparatus and detection equipment. Background Technology

[0002] Aromatic amines are a class of organic compounds in which an amino group is directly attached to an aromatic ring. They are characterized by high boiling points or low melting points, typically have a distinctive odor, and are highly toxic; some varieties are even carcinogenic. These substances are widely used in the synthesis of dyes, pharmaceuticals, and pesticides.

[0003] In the textile industry, commonly used azo dyes can produce aromatic amines upon contact with sweat and other substances. These aromatic amines are easily absorbed through the skin, causing allergies, and long-term exposure can even lead to cancerous changes in human cells, posing a significant threat to human health. Currently, monitoring the use of banned azo dyes has become one of the most important quality control items in the textile and apparel trade. my country's national standard GB / T 17592 specifies 24 aromatic amines prohibited in textiles, such as benzidine, p-chloroaniline, and o-toluidine. Current testing methods primarily involve reacting textile samples in a citrate buffer solution to reduce the azo dyes to the potentially prohibited aromatic amines. The aromatic amines are then extracted, concentrated, and brought to a fixed volume before their content is analyzed. The extraction of aromatic amines is one of the core steps affecting the test results.

[0004] In existing technologies, the extraction methods for aromatic amines typically involve the combined use of multiple chemical reagents and are quite cumbersome. Taking the patent application number 201710012591.8, "Method for GC-MS Determination of Aromatic Amines in Cigarette Smoke Based on Liquid-Liquid Microextraction," as an example, the collected aromatic amines require the addition of sodium hydroxide aqueous solution to adjust the pH to 12-13, followed by the addition of a certain amount of extraction solvent toluene and salting-out agent anhydrous sodium sulfate, followed by shaking, centrifugation, and the removal of the upper toluene layer. This layer is then derivatized with heptafluorobutyric anhydride, purified by dispersed solid-phase extraction, and finally used for detection. The extraction methods used in other existing technologies are largely similar. In the field of textile testing, disposable diatomaceous earth columns are typically used as the dispersed solid phase, while other organic extractants are adjusted according to the detection target. Existing detection methods result in high extraction and detection costs for aromatic amines. Furthermore, the use of large amounts of chemical reagents and other consumables makes these methods environmentally unfriendly and also impacts the health of operators.

[0005] The textile and apparel industry is an important industry in my country, and the demand for textile and apparel testing is enormous. Therefore, there is an urgent need for a time-saving, efficient, and environmentally friendly aromatic amine extraction method to meet the huge demand for aromatic amine detection. Summary of the Invention

[0006] One of the objectives of this invention is to provide an aromatic amine extraction method that is more time-saving, efficient, and environmentally friendly by employing a dynamic extraction process, involving fewer types of chemical reagents and consumables.

[0007] The second objective of this invention is to provide a hollow fiber membrane extraction device for use in conjunction with the above-mentioned extraction method.

[0008] The third objective of this invention is to provide an organic matter detection device equipped with the aforementioned hollow fiber membrane extraction apparatus.

[0009] The fourth objective of this invention is to provide a method for using the aforementioned organic matter detection device.

[0010] This invention is achieved through the following technical solution:

[0011] In a first aspect, the present invention provides an aromatic amine extraction method applicable to a hollow fiber membrane extraction device, comprising a working tube and a hollow fiber membrane arranged in the working chamber of the working tube, wherein a receiving chamber is formed in the hollow fiber membrane; the method comprises the following steps: S1. Adjusting the pH value of the sample solution to be extracted to 5-7, and placing the sample solution and extractant into separate liquid collection containers; S2. Transferring the extractant to the receiving chamber and completing the filling; S3. Transferring the sample solution to the working chamber and circulating it unidirectionally, while maintaining its flow outside the hollow fiber membrane, controlling the circulation rate of the sample solution to 0.1-5 mL / min, and the extraction duration to 20-60 min.

[0012] All aromatic amines contain hydrophobic aromatic rings and hydrophilic amino groups, which gives them surfactant-like properties, meaning the interfacial tension between the aqueous phase containing the aromatic amine and the organic phase containing the extractant is low. Therefore, it is generally believed that the relative flow between the two phases during dynamic extraction can easily lead to emulsification. Consequently, dynamic extraction, a time-saving and efficient extraction method for other substances, has not been fully utilized in the field of aromatic amine extraction.

[0013] After using the hollow fiber membrane extraction device, the inventors successfully introduced a highly efficient dynamic extraction method into the field of aromatic amine extraction.

[0014] In the prior art, patent application number 201510283101.9 discloses a device for coupling hollow fiber membrane liquid chromatography-microextraction with liquid chromatography and a method for online quantitative analysis of polysaccharide components. This involves a hollow fiber membrane extraction device, which states that "the hollow fiber membrane wall has a porous structure with selective permeability, while the extraction solvent on the membrane wall has adsorption selectivity, which can play a strong role in sample purification." The patent also demonstrates a method for extracting polysaccharide components. However, compared to the prior art, when the target to be extracted is an aromatic amine, emulsification occurs during dynamic extraction. The resulting emulsion not only clogs the micropores of the hollow fiber membrane (typically with a pore size of only 0.2 μm) but may also clog other fine tubing in the system, ultimately leading to extraction failure.

[0015] However, in this invention, by adjusting the pH value of the sample solution, controlling the circulation rate of the sample solution, and controlling the extraction duration, the inventors successfully used appropriate processing parameters to ensure good mass transfer efficiency when using a hollow fiber membrane extraction device, while also preventing emulsification and other phenomena that could hinder the smooth progress of the extraction process or even damage the equipment.

[0016] Meanwhile, the extraction targets in this invention are taken from textile test samples, which typically contain dozens of aromatic amines. The chemical activity and mass transfer efficiency of various aromatic amines differ, but the processing parameters listed in this invention ensure optimal extraction results for all dozens of aromatic amines in the extraction targets. This achieves a better range of processing parameters amidst complex and multifaceted influencing factors, thus meeting the demands of complex extraction operations.

[0017] With the introduction of the dynamic extraction method described above, the chemical reagents used in the extraction process of this invention are mainly extractants, and the requirements for dispersing solid phases are no longer necessary. This significantly reduces the reagent consumption of the extraction method in this invention and improves its environmental friendliness.

[0018] As a further improvement of the present invention, in S1, the pH value of the sample solution is adjusted to 5.5~6.5.

[0019] As a further improvement of the present invention, 3. In S3, the circulation rate is controlled to be 1~3 mL / min and the extraction duration is 30~50 min.

[0020] As a further improvement of the present invention, the extractant is any one of n-octanol, toluene, n-hexane, n-butyl acetate, and [C6MIM]PF6.

[0021] The extractant selected in this invention not only possesses high extraction and enrichment efficiency for aromatic amines, but also ensures that it has similar polarity to the hollow fiber membrane material, is insoluble in the aqueous phase, has low volatility, and a certain viscosity, thus enabling it to stably fill the pores of the hollow fiber membrane wall for extraction. Furthermore, using the aforementioned extractant can reduce or even avoid emulsification during dynamic extraction, thereby ensuring smooth extraction.

[0022] As a further improvement of the present invention, the sample solution contains at least one or more of the following: 4-aminobiphenyl, 2-methoxy-5-methylaniline, benzidine, 4,4'-methylene-di-(2-chloroaniline), 4-chloro-o-toluidine, 4,4'-diaminodiphenyl ether, 2-naphthylamine, 4,4'-diaminodiphenyl sulfide, p-chloroaniline, o-toluidine, 2,4-diaminoanisole, 2,4-diaminotoluene, 4,4'-diaminodiphenylmethane, 2,4,5-trimethylaniline, 3,3'-dichlorobenzidine, o-aminoanisole, 3,3'-dimethoxybenzidine, 2,4-dimethylaniline, 3,3'-dimethylbenzidine, 2,6-dimethylaniline, and 3,3'-dimethyl-4,4'-diaminodiphenylmethane.

[0023] Secondly, the present invention provides a hollow fiber membrane extraction device, characterized in that it is adapted to any of the above-mentioned aromatic amine extraction methods, comprising a sample container, an extractant container, a working tube, a hollow fiber membrane arranged in the working chamber of the working tube, a receiving line, and a working line, wherein a receiving chamber is formed in the hollow fiber membrane; the receiving line sequentially connects the extractant container and the receiving chamber; the working line starts from the sample container, connects to the working chamber, and then connects back to the sample container to form a circulation route.

[0024] As a further improvement of the present invention, the aperture of the receiving chamber is 550~650μm, the wall thickness of the hollow fiber membrane is 150~250μm, and the aperture of the screening holes arranged on the wall surface of the hollow fiber membrane is 0.15~0.25μm.

[0025] The dimensions of each structure in the aforementioned hollow fiber membrane achieve a balance between extraction efficiency and the prevention of emulsification during dynamic extraction. Specifically, the dimensions of the receiving chamber and the pore size of the screening holes are used to fill the extractant. This ensures that the hollow fiber membrane can hold sufficient extractant to achieve the extraction of as many aromatic amines as possible, while preventing extractant leakage due to excessively large pore sizes. Furthermore, the pore size of the screening holes effectively controls the contact area between the extractant and the phase to be extracted, thereby reducing the possibility of emulsification occurring when the two phases come into contact during dynamic extraction.

[0026] As a further improvement of the present invention, a delivery pump is provided on both the receiving line and the working line, and the delivery pump is electrically connected to the control device.

[0027] Thirdly, the present invention provides an organic matter detection device, which includes at least a six-way valve, a liquid eluent kit and a liquid chromatography column kit connected to the six-way valve; and further includes any of the above-mentioned hollow fiber membrane extraction devices, wherein the receiving chamber of the hollow fiber membrane extraction device is connected to the six-way valve.

[0028] Fourthly, the present invention provides a method for detecting aromatic amines, which is adapted to the above-mentioned organic matter detection equipment; comprising the following steps: S1. Keeping the six-way valve in the first state so that the hollow fiber membrane extraction device is disconnected from the quantitative loop in the six-way valve, and performing extraction in the hollow fiber membrane extraction device according to any of the above-mentioned aromatic amine extraction methods; S2. After extraction, the six-way valve is switched to the second state, and the extractant is delivered to the quantitative loop; S3. Switching the six-way valve back to the first state, the liquid eluent output from the liquid phase eluent kit enters the liquid chromatography column kit for detection after passing through the quantitative loop, wherein the liquid phase eluent contains a first mobile phase and a second mobile phase. At the start of detection, 15% of the first mobile phase and 85% of the second mobile phase are used, and within 45 minutes, the concentration is linearly changed to 80% of the first mobile phase and 20% of the second mobile phase, and this concentration is maintained for 5 minutes.

[0029] Typically, after extraction, the target amine is directly added to the detection step to determine its content, etc. Therefore, this invention also provides a method for detecting aromatic amines, which completes the preliminary work using the aforementioned aromatic amine extraction method, and then proceeds to determine the content of the aromatic amine. In this method, because the extraction method involved is time-saving, efficient, and has good extraction effects on various types of aromatic amines, the overall efficiency of the detection method is greatly improved, and the content of the target aromatic amine in the sample can be measured more accurately.

[0030] The beneficial effects of this invention are as follows:

[0031] (1) The aromatic amine extraction method provided by the present invention introduces a dynamic extraction process, which greatly improves the extraction efficiency. Compared with the original static extraction process, it reduces the types and consumption of chemical reagents, thereby reducing the detection cost and the impact on the environment and the health of operators.

[0032] In particular, this invention controls key parameters such as sample solution pH, circulation rate and extraction duration, effectively avoiding emulsification in the dynamic extraction process. This ensures that when using the hollow fiber membrane extraction device, it not only guarantees good mass transfer efficiency but also prevents problems such as pipeline blockage caused by emulsification, thereby ensuring that the extraction work can be carried out smoothly and efficiently.

[0033] The improved extraction method described above can also be applied to the simultaneous extraction of various aromatic amines with different chemical activities and mass transfer efficiencies.

[0034] In summary, the extraction method of this invention can meet the complex extraction needs in large-scale textile testing, and ensures high extraction efficiency and relatively low cost.

[0035] (2) The hollow fiber membrane extraction device of the present invention has a reasonable structural design. The working line forms a circulating flow of sample liquid, which is combined with the receiving line to transport the extractant, thus realizing a dynamic extraction process. At the same time, the receiving chamber pore size, hollow fiber membrane wall thickness and screening pore size have been optimized in the present invention. While ensuring stable filling of extractant and high extraction efficiency, the contact area between the two phases is effectively controlled, further reducing the probability of emulsification. The cooperation between the delivery pump and the control device also makes the parameter control of the extraction process more precise and automated.

[0036] (3) The organic matter detection equipment provided in this invention combines the extraction and detection processes. By switching the six-way valve, efficient extraction and subsequent rapid and accurate detection can be achieved. In the corresponding aromatic amine detection method, by optimizing the ratio of the liquid phase rinsing solution and the gradient elution program, the various aromatic amine substances after extraction can be accurately separated and quantitatively analyzed, further improving the accuracy and reliability of the detection. This makes the aromatic amine detection method in this invention applicable to the aromatic amine detection needs in textiles and has good potential for widespread use. Attached Figure Description

[0037] The accompanying drawings are provided below to illustrate the preferred embodiments of the invention and to aid in understanding the objectives and advantages of the invention, wherein:

[0038] Figure 1 This is a schematic diagram showing the connection relationships between components in a hollow fiber membrane extraction device;

[0039] Figure 2 This is a schematic diagram showing the connection relationships between components in an organic matter detection device. Detailed Implementation

[0040] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0042] Example 1:

[0043] This embodiment provides an aromatic amine extraction method, which is applicable to hollow fiber membrane extraction devices.

[0044] like Figure 1 As shown, the hollow fiber membrane extraction device includes a sample container A01, an extractant container A02, a working tube A03, a hollow fiber membrane A04, a receiving circuit A05, and a working circuit A06. The hollow fiber membrane A04 mainly comprises a wall, a receiving chamber A04-1 enclosed by the wall, and screening holes formed on the wall. Multiple hollow fiber membranes A04 are arranged within the working chamber A03-1 of the working tube A03. Sealing plugs A03-2 are arranged at both ends of the working tube A03. The ends of the multiple hollow fiber membranes A04 are inserted into and fixed to the sealing plugs A03-2. Epoxy resin is filled in the contact gap between the sealing plugs A03-2 and the hollow fiber membranes A04 to further enhance the sealing effect. Simultaneously, a flow channel is provided on the sealing plugs A03-2 for the sample liquid to flow into the working chamber A03-1. In this embodiment, the receiving line A05 starts from the extractant container A02 and connects it to the receiving chamber A04-1; while the working line A06 starts from the sample container A01, connects to the working chamber A03-1 and then back to the sample container A01 to form a circulation route; the flow channel on the sealing plug A03-2 ensures that the working route can input the sample liquid into the working chamber A03-1, while the sealing measures on the sealing plug A03-2 ensure that the sample liquid will not seep into the hollow fiber membrane A04.

[0045] Based on the hollow fiber membrane extraction device described above, the aromatic amine extraction method in this embodiment mainly includes the following steps:

[0046] S1. Adjust the pH of the sample solution to be extracted to 6. At this pH value, the substances to be extracted in the sample solution can be kept in molecular state, which makes it easier for them to be extracted by the extractant. Then, put the sample solution and the extractant into the respective liquid collection containers. In this embodiment, the sample solution used is derived from textile testing samples, obtained using the reaction method in the national standard "Determination of Banned Azo Dyes in Textiles" (GB / T 17592-2024). Exemplarily, in this embodiment, the sample is obtained through the following steps: a representative textile sample is taken and cut into 5mm × 5mm pieces; 1.0g is weighed into a reaction tube, and 17mL of citrate buffer solution preheated to 70±2℃ is added. The reactor is sealed, and the sample is vigorously shaken to immerse all samples in the liquid; then, it is kept in a (70±2)℃ water bath for 30min; next, the reactor is opened, and 3.0mL of sodium dithionite solution is accurately added, immediately sealed, and shaken. The reactor is then kept in a (70±2)℃ water bath for 30min; the reactor is removed and cooled to room temperature within 2min to obtain the sample solution. In this process, the textile testing sample is first reduced in the citrate buffer solution medium. Testing shows that the pH value of the sample solution after the reaction is approximately 6, which directly meets the required pH conditions, further reducing the pH adjustment work required for the sample solution.

[0047] S2. Transfer the extractant [C6MIM]PF6 to the receiving chamber A04-1 and complete the filling.

[0048] S3. Transfer the sample solution into the working chamber A03-1 and circulate it unidirectionally, while maintaining its flow outside the hollow fiber membrane A04. Control the circulation rate of the sample solution at 2 mL / min and the extraction duration at 40 min; wherein, the sample solution is mainly composed of... Figure 1 Taking the perspective of the sample liquid as an example, the sample liquid enters the working chamber A03-1 from the upper flow channel of the right sealing plug A03-2, and finally flows out from the lower flow channel of the left sealing plug A03-2 and flows back into the sample container A01, thereby achieving unidirectional circulation.

[0049] Preferably, in this embodiment, the receiving chamber A04-1 of the hollow fiber membrane A04 has a pore size of 600 μm and a wall thickness of 200 μm, and the screening holes arranged on the wall surface of the hollow fiber membrane A04 have a pore size of 0.2 μm.

[0050] Preferably, such as Figure 1 As shown, both receiving line A05 and working line A06 are equipped with conveying pumps A07. The conveying pumps A07 are electrically connected to the control device A08. That is, after the control device A08 outputs an electrical signal, it can control the switching on and off of the conveying pumps A07, the output flow rate, etc., thereby realizing precise control of parameters such as flow rate and the start and stop of conveying work.

[0051] Example 2:

[0052] This embodiment provides a method for detecting aromatic amines, which is applicable to organic matter detection equipment.

[0053] like Figure 2 As shown, the organic matter detection device includes a six-way valve B01, a quantitative ring B01-1 disposed within the six-way valve B01, a liquid phase eluent kit B02, a liquid phase column kit B03, and the hollow fiber membrane extraction device described in Example 1, wherein the liquid phase eluent kit B02, the liquid phase column kit B03, and the hollow fiber membrane extraction device are all connected to the six-way valve B01.

[0054] The detection method mainly includes the following steps:

[0055] S1. Before formally carrying out content detection, extraction work is carried out first; therefore, the six-way valve B01 needs to be kept in the first state. During this period, the hollow fiber membrane extraction device is disconnected from the quantitative loop B01-1, while the liquid eluent output from the liquid eluent kit B02 flows through the quantitative loop B01-1 and is continuously input into the liquid chromatography column kit B03 to maintain the state of being ready for detection. At the same time, the extraction work is carried out independently in the hollow fiber membrane extraction device according to the extraction method in Example 1.

[0056] S2. After the extraction is completed, switch the six-way valve B01 to the second state. The liquid eluent kit B02 is directly connected to the liquid chromatography column kit B03 to continuously supply liquid eluent. The receiving chamber A04-1 is connected to the quantitative loop B01-1 in the six-way valve B01. Therefore, the extractant containing the target analyte can directly enter the quantitative loop B01-1, and the original liquid eluent in the quantitative loop B01-1 is discharged accordingly, so that the extractant containing the target analyte fills the quantitative loop B01-1.

[0057] S3. After the filling of the quantitative loop B01-1 is completed, the six-way valve B01 is switched back to the first state. The liquid eluent kit B02 is connected to the liquid chromatography column kit B03 after passing through the quantitative loop B01-1. During this period, the liquid eluent will carry the analyte in the quantitative loop B01-1 into the liquid chromatography column kit B03 for detection. In this embodiment, the liquid eluent contains methanol as the first mobile phase and sodium acetate (pH=3.6) at 0.01 mol / L as the second mobile phase. At the start of detection, 15% of the first mobile phase and 85% of the second mobile phase are used. Within 45 minutes, the first mobile phase and 20% of the second mobile phase are linearly converted to 80% and 20% of the first mobile phase and maintained at this amount for 5 minutes to carry out the detection of aromatic amine content.

[0058] Method evaluation:

[0059] In this embodiment, the extraction method in Example 1 and the detection method in Example 2 are evaluated. For experimental methods where specific conditions are not specified, they are generally determined according to national standards. If no corresponding national standard exists, they are performed according to generally accepted international standards, standard conditions, or conditions recommended by the manufacturer.

[0060] Firstly, this embodiment provides an evaluation of the detection method based on aromatic amine standard working solutions. In this example, five groups of 20 mL aromatic amine standard working solutions with different gradient concentrations were obtained. The concentration ranges of different components in the aromatic amine standard working solutions are shown in Table 1. The detection method described in Example 2 was used to perform parallel measurements three times for each aromatic amine standard working solution at different concentrations. The detection results were then statistically analyzed, and the linear range, correlation coefficient, limit of quantitation, and enrichment factor of each component in the aromatic amine standard working solution were calculated to verify the detection capability of the method. The final test results are shown in Table 2.

[0061] Table 1 Initial Concentration Range of Aromatic Amine Standard Working Solutions .

[0062] Table 2 Summary of Test Results ...

[0063] As can be seen from the test results in Table 2, the detection method of this invention covers a wide linear range when dealing with different concentrations of the test objects. At the same time, the correlation coefficients of various aromatic amines in the standard working solution within the linear range are all greater than 0.99, indicating that when the concentration of the aromatic amines used as test objects changes, the concentration detected after extraction and enrichment will also change accordingly, and this change is linear and corresponds to the change in the initial concentration. This shows that the detection method of this invention can distinguish the concentration changes of the test objects and respond accordingly, and has good accuracy.

[0064] Furthermore, as shown in Table 2, the enrichment factor for each detection object in this method reached between 6 and 192 times. The enrichment factor refers to the ratio between the instrument response signal after the aromatic amine is extracted and injected through a hollow fiber membrane and the instrument response signal after direct injection without extraction. The high enrichment factor under this method indicates that this method can amplify and measure the small concentration changes of the aromatic amine to be detected, thus demonstrating that this scheme has high sensitivity.

[0065] Finally, in this embodiment, the detection method provided by the present invention was repeatedly measured 6 times with any intermediate concentration in the linear range in Table 1. After statistical analysis of the detection results, the relative standard deviation was calculated to be less than 10%, indicating that the method has high accuracy.

[0066] Secondly, this embodiment provides an evaluation of the detection method based on actual samples extracted from textiles.

[0067] First, after converting the results obtained from the above-mentioned testing methods, it was found that, using actual samples, the limits of quantitation for all the aromatic amines to be tested in textiles were less than 2 mg / kg, which is far below the relevant limits in the national standard "Determination of Prohibited Azo Dyes in Textiles" (GB / T 17592-2024).

[0068] Secondly, in this embodiment, two positive samples were selected and pretreated using both the method described herein and the method provided in the national standard "Determination of Banned Azo Dyes in Textiles" (GB / T 17592-2024), and then determined by liquid chromatography. The detection results are shown in Table 3.

[0069] Table 3 Summary of Sample Test Results .

[0070] As shown in Table 3, the qualitative test results are consistent, indicating that the sample is positive based on the test results of this invention. Furthermore, the detection method of this invention avoids the use of diatomaceous earth columns and eliminates the need for rotary evaporation concentration after extraction, thus further reducing the loss of aromatic amines in the sample. This results in test results slightly higher than the national standard method, indirectly demonstrating that the detection method of this invention has higher sensitivity and accuracy.

[0071] Overall, the detection method provided in this invention is a detection method that can meet the needs of actual textile sample testing, has practical application value, and is worth promoting.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An aromatic amine extraction method, applicable to a hollow fiber membrane extraction device, comprising a working tube (A03) and a hollow fiber membrane (A04) disposed in a working chamber (A03-1) of the working tube (A03), wherein a receiving chamber (A04-1) is formed in the hollow fiber membrane (A04). Its features are, It includes the following steps: S1. Adjust the pH value of the sample solution to be extracted to 5-7, and put the sample solution and extractant into separate liquid collection containers; S2. Transfer the extractant to the receiving chamber (A04-1) and complete the filling; S3. The sample solution is transferred to the working chamber (A03-1) and circulated in one direction, while maintaining its flow outside the hollow fiber membrane (A04). The circulation rate of the sample solution is controlled to be 0.1~5 mL / min, and the extraction duration is 20~60 min.

2. The aromatic amine extraction method according to claim 1, characterized in that, In S1, the pH of the sample solution is adjusted to 5.5~6.

5.

3. The aromatic amine extraction method according to claim 1, characterized in that, In S3, the circulation rate is controlled at 1~3 mL / min, and the extraction duration is 30~50 min.

4. The aromatic amine extraction method according to claim 1, characterized in that, The extractant is any one of n-octanol, toluene, n-hexane, n-butyl acetate, and [C6MIM]PF6.

5. The aromatic amine extraction method according to claim 1, characterized in that, The sample solution contains at least one or more of the following: 4-aminobiphenyl, 2-methoxy-5-methylaniline, benzidine, 4,4'-methylene-di-(2-chloroaniline), 4-chloro-o-toluidine, 4,4'-diaminodiphenyl ether, 2-naphthylamine, 4,4'-diaminodiphenyl sulfide, p-chloroaniline, o-toluidine, 2,4-diaminoanisole, 2,4-diaminotoluene, 4,4'-diaminodiphenylmethane, 2,4,5-trimethylaniline, 3,3'-dichlorobenzidine, o-aminoanisole, 3,3'-dimethoxybenzidine, 2,4-dimethylaniline, 3,3'-dimethylbenzidine, 2,6-dimethylaniline, and 3,3'-dimethyl-4,4'-diaminodiphenylmethane.

6. A hollow fiber membrane extraction device, characterized in that, An aromatic amine extraction method adapted to any one of claims 1 to 5 comprises a sample container (A01), an extractant container (A02), a working tube (A03), a hollow fiber membrane (A04) disposed in a working chamber (A03-1) of the working tube (A03), a receiving line (A05), and a working line (A06), wherein a receiving chamber (A04-1) is formed in the hollow fiber membrane (A04); The receiving line (A05) is connected in sequence to the extractant container (A02) and the receiving chamber (A04-1). The working line (A06) starts from the sample container (A01), connects to the working chamber (A03-1), and then connects back to the sample container (A01) to form a loop route.

7. The hollow fiber membrane extraction device according to claim 6, characterized in that, The receiving chamber (A04-1) has a pore size of 550~650μm, the hollow fiber membrane (A04) has a wall thickness of 150~250μm, and the screening holes arranged on the wall surface of the hollow fiber membrane (A04) have a pore size of 0.15~0.25μm.

8. The hollow fiber membrane extraction device according to claim 6, characterized in that, Both the receiving line (A05) and the working line (A06) are equipped with conveying pumps (A07), and the conveying pumps (A07) are electrically connected to the control device (A08).

9. An organic matter detection device, comprising at least a six-way valve (B01), a liquid phase eluent kit (B02) and a liquid phase column kit (B03) connected to the six-way valve (B01); characterized in that, It also includes a hollow fiber membrane extraction device according to any one of claims 6 to 8, wherein the receiving chamber (A04-1) in the hollow fiber membrane extraction device is connected to the six-way valve (B01).

10. A method for detecting aromatic amines, characterized in that, Adapted to the organic matter detection device as described in claim 9; comprising the following steps: S1. Keep the six-way valve (B01) in the first state so that the hollow fiber membrane extraction device is disconnected from the metering ring (B01-1) in the six-way valve, and carry out extraction work in the hollow fiber membrane extraction device according to the aromatic amine extraction method according to any one of claims 1 to 5; S2. After extraction is completed, the six-way valve (B01) switches to the second state to deliver the extractant into the metering loop (B01-1); S3. Switch the six-way valve (B01) back to the first state. The liquid eluent output from the liquid eluent kit (B02) enters the liquid chromatography column kit (B03) for detection after passing through the quantitative loop (B01-1). The liquid eluent contains a first mobile phase and a second mobile phase. At the start of detection, 15% of the first mobile phase and 85% of the second mobile phase are used. Within 45 minutes, the concentration is linearly changed to 80% of the first mobile phase and 20% of the second mobile phase, and this concentration is maintained for 5 minutes.

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