Portable automatic device for measuring alkyl phenol pollutants in water

Abstract

This utility model relates to the field of chemical analytical devices, specifically a portable automatic analytical device for alkylphenol contaminants in water. It has a waste outlet and includes a selector valve, an injection valve, an online filter, an injection assembly, a container assembly, a sample processing assembly, and a detection assembly. The selector valve has one common port and ten selectable ports. The injection assembly includes an injection pump B and a buffer ring. The sample processing assembly includes an air pump, a sample tube, a metal bath base, a pretreatment valve, an extraction column, a suction valve, and an injection pump A. Injection pump A is connected to the common port of the suction valve. The output port of the suction valve, one selectable port of the selector valve, and the injection valve are connected via a mixing tee. The air pump, sample tube, pretreatment valve, extraction column, and one selectable port of the selector valve are sequentially connected. The detection assembly includes a column oven, a chromatographic column, and an LED fluorescence detector. This utility model integrates multiple functions into a single device, has a small size, and enables mobile operation and on-site analysis.

Description

Technical Field

[0001] This utility model relates to the field of chemical measuring devices, and in particular to a portable automatic measuring device for alkylphenol pollutants in water. Background Technology

[0002] Alkylphenols (APs), also known as alkylphenols, are organic compounds formed by replacing hydrogen atoms on the aromatic ring of phenol with alkyl groups. Alkylphenols are commonly used as intermediates in organic synthesis, possessing excellent wetting, penetrating, emulsifying, dispersing, solubilizing, and detergency properties, and are currently the main representatives of widely used nonionic surfactants. These compounds are also endocrine disruptors and may affect normal hormone secretion in the human body.

[0003] Currently, the detection of alkylphenols is represented by the national standard "HJ 1192—2021 Water Quality: Determination of Nine Alkylphenol Compounds and Bisphenol A by Solid Phase Extraction / High Performance Liquid Chromatography," which uses high-performance liquid chromatography (HPLC) for separation and determination using a fluorescence detector. The HPLC system consists of functional modules such as a pump, injector, and detector. After the sample is injected into the column, the eluent delivered by the pump washes different substances from the column inlet to the column outlet. Different compounds are separated according to their different migration velocities, generating fluorescence signals on the detector. Quantitative analysis of the compounds can be performed based on the intensity of the fluorescence signals.

[0004] However, conventional liquid chromatographs have the following shortcomings:

[0005] 1. Volume and weight are not suitable for mobile measurement. A typical liquid chromatograph consists of 3-6 different modules and weighs tens or even hundreds of kilograms.

[0006] 2. High testing requirements: Liquid chromatography (LC) testing requires a large number of professional personnel to perform multiple steps, including sample extraction, purification, evaporation to dryness and volume adjustment, and chromatographic analysis, according to the HJ 1192—2021 standard for the determination of alkylphenol compounds and bisphenol A. Operators need basic chemical experimental training, which inconveniences the measurement process and increases labor costs.

[0007] 3. In situations requiring field sampling, such as responding to sudden pollution incidents, liquid chromatography is not suitable for on-site testing and cannot provide timely results. Utility Model Content

[0008] The purpose of this invention is to address the problems existing in the background technology by proposing a portable automatic determination device for alkylphenol pollutants in water. The device is simplified into a portable system consisting of a pump, multiple valve switching, an excimer laser ultraviolet light source, and a fluorescence detector. It integrates multiple functions such as automatic sample extraction and purification, automatic drying and volume adjustment, automatic sample injection, and automatic chromatographic elution and quantification into a single device, all within a small body weighing approximately 10 kg. The device has its own data system and battery, enabling mobile operation and on-site analysis.

[0009] The present invention provides a portable automatic determination device for alkylphenol contaminants in water, comprising a waste outlet, a selection valve, an injection valve, an online filter, an injection assembly, a container assembly, a sample processing assembly, and a detection assembly. The selection valve has a common port and ten selectable ports, each individually connected to the common port via adjustment. The injection valve is a two-position six-way valve with six ports, two phases, and a built-in quantitative loop. The online filter is connected between one selectable port of the selection valve and the injection valve. The injection assembly includes an injection pump B and a buffer ring, with the injection pump B, the buffer ring, and the common port of the selection valve sequentially connected. The container assembly is connected to the six selectable ports of the selection valve. The sample processing assembly includes… The system includes an air pump, sample tube, metal bath base, pretreatment valve, extraction column, aspiration valve, and syringe pump A. Syringe pump A is connected to the common terminal of the aspiration valve. The input terminal of the aspiration valve is connected to container seven. The output terminal of the aspiration valve, one selection port of the selector valve, and the injection valve are connected via a mixing tee. The sample tube is inserted into the metal bath base. The air pump, sample tube, pretreatment valve, extraction column, and one selection port of the selector valve are connected in sequence. The detection assembly includes a column oven, chromatographic column, and LED fluorescence detector. The chromatographic column is installed inside the column oven. The injection valve, chromatographic column, and LED fluorescence detector are connected in sequence. The remaining selection port of the selector valve, the pretreatment valve, the injection valve, and the LED fluorescence detector are all connected to the waste port.

[0010] Preferably, the buffer ring is an inert tubing with an internal volume matching the range of the syringe pump B.

[0011] Preferably, the selector valve includes a first valve body, a first stator located inside the first valve body, and a first rotor rotating around the outer circumference of the first stator. The first rotor has a slot, and a common port and ten selector ports are located on the first valve body. When one of the slots faces a selector port, the selector port is connected to the common port.

[0012] Preferably, the injection valve includes a second valve body, a second stator located within the second valve body, and a second rotor rotating around the outer circumference of the second stator.

[0013] Preferably, both the selector valve and the injection valve are made of stainless steel or polyetheretherketone.

[0014] Preferably, the column oven has heating elements for heating and thermocouples for temperature detection.

[0015] Preferably, it also includes a battery for power supply.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects:

[0017] This invention simplifies the device and successfully integrates multiple functions, including automatic sample purification and concentration, automatic sample injection, and automatic chromatographic elution and quantification. The equipment is integrated into a compact unit weighing approximately 10 kg. It features a built-in data system and battery, enabling mobile operation and on-site analysis. The entire measurement process is fully automated, automatically executing all pretreatment, analysis, and self-cleaning steps. The measured results are automatically compared with those obtained from built-in standards. No human intervention is required during the process; operators do not need experimental experience or specialized training to use it conveniently, meeting the requirements for rapid response and on-site testing in the field. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model;

[0019] Figure 2 Exploded view of the structure of the fluorescence detector of the excimer laser ultraviolet light source;

[0020] Figure 3 To simulate the test results of the water sample, 20 ng / mL of 4-hexylphenol was added to the standard.

[0021] Figure reference numerals: 1. Syringe pump B; 2. Buffer ring; 3. Selector valve; 4. Container 1; 5. Container 2; 6. Container 3; 7. Container 4; 8. Container 5; 9. Container 6; 10. Air pump; 11. Sample tube; 12. Metal bath base; 13. Pretreatment valve; 14. Extraction column; 15. Container 7; 16. Aspiration valve; 17. Syringe pump A; 18. Injection valve; 19. In-line filter; 20. Column oven; 21. Chromatographic column; 22. LED fluorescence detector; 220. Excimer laser source; 221. Focusing lens 1; 222. Quartz flow cell; 2221. Cell inlet; 2222. Cell outlet; 223. Filter; 224. Focusing lens 2; 225. Phototube; 23. Battery; 24. Data system. Detailed Implementation

[0022] like Figures 1-3As shown in this embodiment, a portable automatic determination device for alkylphenol contaminants in water is provided. It includes a waste outlet, a selection valve 3, an injection valve 18, an online filter 19, a battery 23, an injection assembly, a container assembly, a sample processing assembly, and a detection assembly. The battery 23 powers the device to ensure its portability and field operation capability; for example, a 24V adapter or a lithium battery can be used as the system power source. An external data system 24 integrates and controls the entire determination device.

[0023] Selector valve 3 is used to select different liquid pathways. A typical configuration conforming to standard HJ 1192—2021 is a ten-way selector valve, having one common port and ten selector ports (numbered A, B, C, D, E, F, G, H, I, and J) that can be individually connected to the common port by adjustment. Selector valve 3 includes a first valve body, a first stator located inside the first valve body, and a first rotor rotating around the outer circumference of the first stator. The first rotor has slots. Both the common port and the ten selector ports are located on the first valve body. As the first rotor rotates, when a slot connects the common port and a numbered selector port, that pathway is connected to the common port; conversely, when a slot faces a selector port, that selector port is connected to the common port. Selector valve 3 is made of stainless steel or polyetheretherketone (PEEK), an inert material that does not react with the analyte or the reagents used.

[0024] The injection valve 18 is a quantitative loop with a defined internal volume, used to contain the analyte according to the internal volume of the loop and introduce it into a high-pressure liquid chromatography flow path. The injection valve 18 is a two-position six-way valve with ports 1, 2, 3, 4, 5, and 6, offering two selectable phases. In one phase, ports 1-2, 3-4, and 5-6 are connected in pairs; in the other phase, ports 1-6, 2-3, and 4-5 are connected in pairs. The internal volume is typically 30 μL according to standard HJ1192—2021. The injection valve 18 includes a second valve body, a second stator located within the second valve body, and a second rotor rotating around the outer circumference of the second stator. The injection valve 18 is made of stainless steel or polyetheretherketone (PEEK), an inert material that does not react with the analyte or reagents used.

[0025] The in-line filter 19 is connected between the selection port I of the selection valve 3 and the injection valve 18. The in-line filter 19 is used to filter out small amounts of particulate matter that may be present in the sample, preventing system clogging. The in-line filter 19 typically uses a sieve plate or filter element with micropores as the filter material. The filter element and corresponding sleeve are made of inert materials that do not react with the analyte or reagents used, such as sintered stainless steel sieve plates.

[0026] The injection assembly includes a syringe pump B1 and a buffer ring 2, configured according to the required reagent volume. A typical configuration suitable for standard HJ1192—2021 is a syringe pump paired with a 50mL high-pressure syringe, with infusion volume increments of 0.01mL and a buffer tube volume of 10mL. Smaller or larger syringes can be used as needed. The common port of syringe pump B1, buffer ring 2, and selector valve 3 are connected sequentially. Buffer ring 2 is an inert tubing with an internal volume matching the flow rate of syringe pump B1, ensuring that when syringe pump B1 draws a specific amount of liquid, the drawn liquid only enters buffer ring 2 and does not enter syringe pump B1, thus preventing syringe contamination. Syringe pump B1 and selector valve 3 are pressure-resistant to the 20MPa required for column 21 operation.

[0027] The container assembly is connected to the six selection ports of the selector valve 3. Specifically, the container assembly includes container 4, container 5, container 6, container 7, container 8, and container 9. The six containers are used in sequence to hold the sample to be tested, n-hexane, dichloromethane, methanol, pure water, and alkylphenol standard mixture, respectively. Containers 4, 5, 6, 7, 8, and 9 are connected in sequence to selection ports A, B, C, D, E, and F of the selector valve 3, respectively.

[0028] The sample processing assembly includes an air pump 10, a sample tube 11, a metal bath base 12, a pretreatment valve 13, an extraction column 14, a suction valve 16, and a syringe pump A17. The suction valve 16 is a two-position three-way valve. The syringe pump A17 is connected to the common terminal of the suction valve 16. The input terminal (NO terminal) of the suction valve 16 is connected to a container 15, which is an acetonitrile storage tank containing acetonitrile. The output terminal (NC terminal) of the suction valve 16, the selection port J of the selector valve 3, and the port 1 of the injection valve 18 are connected via a mixing tee. The selection port J is the mobile phase output port. The suction valve 16 is a 50mL high-pressure syringe used to draw the mobile phase A (acetonitrile) used in chromatographic gradient elution according to standard HJ 1192—2021, with an infusion volume step of 0.01mL. The air pump 10, sample tube 11, the COM port of the pretreatment valve 13, the extraction column 14, and the selection port G of the selector valve 3 are connected sequentially. Extraction column 14 is used to extract the target substance from the sample. According to section 6.5 of standard HJ 1192—2021, it has a specification of 250 mg / 6 ml, is made of polypropylene or glass, and uses a styrene-divinylbenzene copolymer or other equivalent extraction column as the packing material. The pretreatment valve 13 downstream of extraction column 14 is a two-position three-way solenoid valve used to switch between the eluent and waste liquid during pretreatment, ensuring automatic execution of the pretreatment process.

[0029] Sample tube 11 is a disposable syringe, which is inserted into the metal bath base 12. The metal bath base 12 is made of metal and uses a PT100 thermocouple for temperature feedback and a PTC ceramic heating element to heat the sample tube 11. The metal bath base 12 has an opening at the top for inserting the sample tube 11, with a through hole at the bottom, connected to the NC port of the pretreatment valve 13 via a pipeline. When it is necessary to extract or inject liquid into the sample tube 11, the liquid is drawn or injected through the bottom of the sample tube 11 via the selection port G of the selection valve 3. Both the metal bath base 12 and the sample tube 11 are made of inert materials that do not react with the analyte or reagents used. The base material is stainless steel, and the sample tube is a disposable polypropylene syringe. A Luer connector is used for the insertion interface. In order to dry the solid-phase extraction eluent to remove solvent as required in section 7.2.3 of standard HJ 1192—2021, this measuring device has a separate air pump 10 that can provide compressed air to the sample tube 11 to dry the solvent in the eluent under the auxiliary conditions of heating.

[0030] The detection assembly includes a column oven 20, a chromatographic column 21, and an LED fluorescence detector 22. The column oven 20 is a heating container with temperature feedback control, which maintains the chromatographic column 21 within it at a stable separation temperature according to method requirements. The temperature is set to 40℃ according to section 12.3 of standard HJ 1192—2021. The column oven 20 has a PTC ceramic heating element for heating and a PT100 thermocouple for temperature detection. The chromatographic column is the core component for separation; its stainless steel shell is filled with powdered packing material to provide separation capability. The chromatographic column 21 is selected as a C18 packed column and is installed inside the column oven 20. Port 6 of the injection valve 18 is connected to the inlet of the chromatographic column 21, and the chromatographic column 21 and LED fluorescence detector 22 are connected in sequence.

[0031] LED fluorescence detector 22 is used to measure the real-time fluorescence emission of the effluent from chromatographic column 21. It uses a 222nm excimer laser ultraviolet light source as the light source and a dedicated fluorescence detector with a 315nm filter is installed in front of the photocell used for detection. Figure 2 As shown, the LED fluorescence detector 22 includes an excimer laser source 220, a first focusing lens 221, a quartz flow cell 222, a filter 223, a second focusing lens 224, and a phototube 225. The quartz flow cell 222 has a cell inlet 2221 and a cell outlet 2222. The positions and connections between the relevant structures are based on existing fluorescence detectors. The syringe pump A17 and the suction valve 16 are pressure-resistant enough to meet the 20 MPa operating requirements of the chromatographic column 21. After the chromatographic effluent is introduced into the quartz flow cell 222, a photocell is used to measure the absorption of the effluent by the excimer laser ultraviolet light source, and the efflux amount of alkylphenols is measured.

[0032] The selection port H of the selector valve 3, the NO port of the pretreatment valve 13, the injection valve 18, and the LED fluorescence detector 22 are all connected to the waste liquid port. The selection port H is connected to an open pipeline, which can be used as an air inlet when the syringe pump draws in air and as a waste liquid outlet when the syringe pump exits.

[0033] The assay requires the use of water and an organic solvent (a mixture of 50% methanol and 50% acetonitrile). Calibration of the apparatus requires the use of standards containing known concentrations of alkylphenols. All reagents should be stored in appropriate containers. All tubing should be inert and suitable for liquid chromatography systems, and should be made of 1 / 16-inch stainless steel or polyetheretherketone (PEEK) tubing.

[0034] This measuring device can perform the following four functions: 1. Liquid aspiration and infusion with self-cleaning function; 2. Automatic solid-phase extraction purification pretreatment of samples; 3. Column rinsing and elution; 4. Liquid chromatography sample filtration, injection and tubing self-cleaning.

[0035] Function 1: Features self-cleaning function, allowing for aspiration and infusion of fluids at specified volumes and rates.

[0036] If a liquid of volume V needs to be drawn from port M and discharged to port N, followed by cleaning of the pipeline, and the ports M and N are arbitrarily set according to application requirements, then the specific process is as follows:

[0037] Selector valve 3 switches to selector port H, discharging all remaining liquid and bringing the piston to its furthest point. Then, full-scale air is drawn in from selector port H, and syringe pump B1 is purged several times to ensure that the liquid is emptied from the common port to the outlet of selector port H.

[0038] Selector valve 3 is switched to selector port D, and syringe pump B1 draws 10 mL of methanol. Then, selector valve 3 is switched to selector port H, drawing in 0.1-0.2 mL of air. Afterward, it is switched to any designated suction port M, drawing in volume V at a specified rate. The drawn-in air separates the 10 mL of methanol from volume V of a certain liquid, preventing the two zones from mixing.

[0039] Then, the syringe pump B1 is switched to any desired output port N, and at a specified speed, the piston is pushed out by a volume V, drawing in a volume V of liquid from the buffer ring 2 through port M and pushing it to port N. After the infusion is complete, the selector valve 3 is switched to selector port H, expelling the remaining air and 10 mL of methanol. The expelled methanol flushes away any remaining liquid from port M within the buffer ring 2, achieving self-cleaning of the tubing.

[0040] Function 2: Automated solid-phase extraction purification pretreatment of samples:

[0041] After the solid-phase extraction column 14 and sample tube 11 are installed in the system, if automatic sample pretreatment is required according to sections 7.2.2-7.2.3 of standard HJ 1192—2021, it can be achieved through the following process:

[0042] Insert the empty sample tube 11, which has a Luer interface at the lower end and an opening at the upper end, into the metal bath base 12. The volume of the sample tube 11 should be 10 mL. Use a 10 mL polypropylene syringe with the piston removed as the sample tube.

[0043] S1. Activation and Sample Loading: After installing the solid-phase extraction column 14 in the system, the syringe pump A17 sequentially draws in 10 ml of n-hexane, 10 ml of dichloromethane, 10 ml of methanol, and 10 ml of experimental water from the corresponding solvent storage containers and pushes them out to select port G to activate the solid-phase extraction column. Then, the water sample awaiting solid-phase extraction purification is loaded into the sample vial (container 4) connected to select port A. Selector valve 3 is switched to select port A, and syringe pump B1 draws in the sample solution. Then, switch to select port G, and syringe pump B1 pushes the sample to be purified onto the solid-phase extraction column 14 at a flow rate of 5 mL / min, according to the flow rate requirements in standard HJ 1192—2021, until all the sample solution has been drawn in and injected into the solid-phase extraction column 14. In this step, the NO port of the pretreatment valve 13 is opened, and the effluent is discharged to the waste port.

[0044] S2. Cleaning: After loading all samples, switch selector valve 3 to selector port D, aspirate 3 mL of methanol, then switch to selector port E, aspirate 7 mL of water. Next, switch to selector port G and push 10 mL of water onto the solid-phase extraction column 14 at a flow rate of 5 mL / min, as required in section 7.2.2 of standard HJ 1192—2021, to clean the solid-phase extraction column 14 and remove interfering substances. At this time, the NO port of pretreatment valve 13 opens, and the effluent is discharged to the waste port.

[0045] S3, Drying the extraction column 14: The syringe pump B1 draws air from the selection port H, then switches to the selection port G to discharge air, drying the solid-phase extraction column 14. At this time, the NO port of the pretreatment valve 13 opens, and the effluent is discharged to the waste liquid port.

[0046] S4. Elution of the target compound: Starting from this step, the NC port of pretreatment valve 13 is opened, and the effluent is delivered to sample tube 11. Hydraulic pump B1 draws 2 mL of methanol from selection port D, then switches to selection port G, pushing the mixture to be mixed into the solid-phase extraction column 14 at a rate of 2 mL / min. Next, syringe pump B1 draws air from selection port H, then switches to selection port G to purge the liquid in the solid-phase extraction column 14 with air, thus purgeing all the eluent into sample tube 11. Hydraulic pump B1 again draws 5 mL of dichloromethane from selection port C, then switches to selection port G, pushing the mixture to be mixed into the solid-phase extraction column 14 at a rate of 2 mL / min. Then, selection valve 3 switches to selection port H, syringe pump B1 draws air from selection port H, then switches to selection port G to purge the liquid in the solid-phase extraction column 14 with air. The solid-phase extraction column 14 was washed sequentially with 2 mL of methanol and 5 mL of dichloromethane in accordance with the requirements of HJ 1192—2021, and the eluent was transferred to an intermediate container to be dried and diluted to a final volume.

[0047] S5. Sample Concentration: After the previous step, sample tube 11 will contain 7 mL of eluent purified by solid-phase extraction. The system will, according to HJ 1192—2021, control the metal bath temperature to 60°C to accelerate drying, and turn on air pump 10 to blow air into sample tube 11, causing the eluent to evaporate completely. After the programmed evaporation time, selector valve 3 will switch to port D and draw 1.0 mL of methanol. Then, selector valve 3 will switch to port G to expel all drawn solvent. Next, selector valve 3 will switch to port H, and syringe pump B1 will draw air from port H. Selector valve 3 will then switch to port G, blowing gas into sample tube 11. Bubbling from below will allow the purified and dried sample to be reconstituted and thoroughly mixed with the aforementioned 1 mL of solvent.

[0048] S6. After the above steps are completed, 1 mL of sample is prepared and stored in sample tube 11.

[0049] Function 3: Column washing and elution:

[0050] In accordance with standard HJ 1192—2021, to achieve the binary gradient elution of acetonitrile (mobile phase A) and water (mobile phase B) as shown in Table 1, before the method begins, syringe pump A17 switches suction valve 16 to port NO to draw 50 mL of acetonitrile from container 15, then switches to port NC, ready to dispense. Selector valve 3 switches to selector port E to draw 50 mL of water, then switches to selector port J, ready to dispense. During elution, syringe pumps A and B work together to deliver the binary gradient solvent according to the ratio required by the method.

[0051] Table 1. Gradient Elution Program Table

[0052]

[0053] During elution, the column oven 20 is used to maintain the column 21 at the separation temperature specified by the method. The column temperature is set to 40°C. During rinsing and elution, the injection valve 18 is in the phase where the three sets of ports 1-2, 3-4, and 5-6 are connected in pairs. The liquid injected into port 1 flows through the flow path 1→2→quantitative loop→5→6→column into the column 21. Ports 3 and 4 are not in the flow path.

[0054] Function 4: Liquid chromatography sample filtration, injection, and tubing self-cleaning.

[0055] After the aforementioned sample purification steps are completed, the sample to be tested, retained in sample tube 11, is filtered and injected into chromatographic column 21. The specific method for achieving self-cleaning of the sample flow through the pipeline is as follows:

[0056] Selector valve 3 is switched to selector port D, and syringe pump B1 draws 10 mL of methanol. Then, selector valve 3 is switched to selector port G, drawing in 0.1-0.2 mL of air. Afterward, it is switched back to selector port G, and a volume of Vs of sample is drawn from the bottom of sample tube 11. The drawn-in air acts as a separator, preventing mixing of the two zones. The volume of the quantitative loop is Vloop, and the sample volume Vs > Vloop.

[0057] Then, switch selector valve 3 to selector port 1, and simultaneously connect injection valve 18 to each of the three sets of ports 1-6, 2-3, and 4-5 in pairs. Push syringe pump B1 out a volume slightly more than Vloop, but not greater than Vs. The previously aspirated sample zone will first be filtered through online filter 19, then injected into port 3, and flow through the sequence 3→2→quantitative loop→5→4 into the quantitative loop. The original liquid in the quantitative loop, as well as the extra injected sample, will be discharged through port 4.

[0058] Then, switch the injection valve 18 to the phase where ports 1-2, 3-4, and 5-6 are connected in pairs. The liquid injected into port 1 will flow through the flow path 1→2→quantitative loop→5→6→column into column 21. Ports 3 and 4 are not in the flow path. Expel all remaining liquid in syringe pump B1 from selector port I. The previously drawn 10 mL of methanol will clean the online filter 19 and injection line, and then be discharged through port 4. At this time, the quantitative loop is filled with the purified sample. Syringe pump B1 again follows the steps in C, drawing 50 mL of water from selector port E, and then using selector port I at the required flow rate and ratio of 1 mL / min in conjunction with syringe pump A17 for chromatographic elution.

[0059] In this embodiment, the quantitative loop volume is 30 μL. During injection, 10 mL of water and 0.2 mL of air are first drawn in, followed by 0.5 mL of sample. After ejecting 0.5 mL of sample to fill the quantitative loop, the injection valve 18 is switched, and the remaining liquid is ejected to clean the injection tubing. Then, 50 mL of water is drawn in and, according to the set ejection selection port J, gradient elution is performed in conjunction with the syringe pump A17. The chromatographic effluent passes through the LED fluorescence detector 22 and is excited by 222 nm ultraviolet light. The 315 nm fluorescence emitted by alkylphenol compounds is filtered by the filter 223 to remove interference from other wavelengths and then focused onto the phototube 225. The resulting signal intensity is proportional to the elution concentration of the alkylphenol compound.

[0060] The following is the detailed procedure for fully automated purification and separation determination, which achieves the same effect as manual solid-phase extraction as described in HJ 1192—2021 and chromatographic elution performed on conventional chromatography:

[0061] Each syringe pump is equipped with a 50mL high-pressure injector, a 10mL buffer loop, a 30μL metering loop, a 222nm excimer laser ultraviolet excitation source, and a fluorescence detector with a 315nm emission filter. Column temperature setting: 40℃. Pretreatment gas drying rate: 8L / min; Pretreatment evaporation temperature: 60℃. Container 2 (5): n-hexane; Container 3 (6): dichloromethane; Container 4 (7): methanol; Container 5 (8): pure water; Container 6 (9): alkylphenol standard: 50ng / mL alkylphenol standard sample.

[0062] As a quantitative basis, after the sample has undergone automated solid-phase extraction and drying to a fixed volume as described above, and the chromatogram is obtained by injection, the standard sample is then determined.

[0063] 1. Following the steps in function 4 above, the system draws the sample from reagent vial F through selection port F and pushes it through selection port I into the metering loop, with a volume of 30 μL. Excess sample is discharged through the waste port. The injection line is then cleaned.

[0064] 2. Following the steps in function 3 above, wash column 21 with acetonitrile-water gradient elution buffer at a flow rate of 1 mL / min for a total elution time of 45 min, and record the fluorescence signal. The data system automatically integrates the peak areas generated by the sample to obtain the peak area As of the sample.

[0065] After the above steps, the system automatically completes the sample pretreatment and determination. The sample in sample tube 11 is then diluted to 1 mL, with the alkylphenol content C = 50As / Astd ng / mL. The pre-extraction concentration is then calculated based on the sample concentration factor. The linear range of this method is 0.1-5 ng / mL, and the reproducibility is based on a 10 ng / mL sample, with RSD < 5% (N = 5).

[0066] This automated analytical apparatus employs a similar structure to liquid chromatography, but simplifies the design and successfully integrates multiple functions such as automated sample purification and concentration, automated injection, automated chromatographic elution, and quantification. All of these functions are integrated into a compact unit weighing approximately 10 kg. The apparatus includes a built-in data system 24 and a battery 23, enabling easy portability and on-site analysis. It combines metering pumps from different locations in the automated injection and infusion modules of a general-purpose liquid chromatograph, achieving a single metering pump for the entire process with a minimal configuration. The entire analytical process is fully automated. After the filtered water sample to be tested is added to the sample tube 11, the system automatically executes all pretreatment, analysis, and self-cleaning steps. The measured results are automatically obtained by comparing them with the results of the built-in standard. No human intervention is required during the process; operators do not need experimental experience or specialized training to use it conveniently, resulting in low labor costs. This automated analytical apparatus is suitable for field testing, meeting the requirements of rapid response and on-site detection, and providing a simple and easy-to-use analytical method for rapid on-site response to emergencies.

[0067] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A portable in-situ automatic measuring device for alkylphenol pollutants, characterized in that, It has a waste liquid outlet, including: Selector valve (3) has a common port and ten selector ports that can be individually connected to the common port by adjustment; The injection valve (18) is a two-position six-way valve with six ports, two phases, and a built-in quantitative loop; An online filter (19) is connected between a selection port of the selection valve (3) and the injection valve (18); The injection assembly includes an injection pump B (1) and a buffer ring (2), and the common port of the injection pump B (1), the buffer ring (2) and the selector valve (3) are connected in sequence; The container assembly is connected to the six selection ports of the selection valve (3); The sample processing assembly includes an air pump (10), a sample tube (11), a metal bath base (12), a pretreatment valve (13), an extraction column (14), a suction valve (16), and a syringe pump A (17). The syringe pump A (17) is connected to the common end of the suction valve (16). The input end of the suction valve (16) is connected to a container (15). The output end of the suction valve (16), a selection port of the selection valve (3), and the injection valve (18) are connected through a mixing tee. The sample tube (11) is inserted into the metal bath base (12). The air pump (10), the sample tube (11), the pretreatment valve (13), the extraction column (14), and a selection port of the selection valve (3) are connected in sequence. The detection assembly includes a column oven (20), a chromatographic column (21), and an LED fluorescence detector (22). The chromatographic column (21) is installed inside the column oven (20), and the injection valve (18), the chromatographic column (21), and the LED fluorescence detector (22) are connected in sequence. The remaining selection port of the selection valve (3), the pretreatment valve (13), the injection valve (18), and the LED fluorescence detector (22) are all connected to the waste liquid port.

2. The portable in-situ alkylphenol contaminant automatic measuring device according to claim 1, characterized in that, The buffer ring (2) is an inert pipeline with an internal volume that matches the range of the syringe pump B (1).

3. The portable automatic detection device for alkylphenol pollutants in water according to claim 1, characterized in that, The selector valve (3) includes a first valve body, a first stator located inside the first valve body, and a first rotor rotating on the outer circumference of the first stator. The first rotor has a slot, and a common port and ten selector ports are located on the first valve body. When the slot is oriented towards a selector port, the selector port is connected to the common port.

4. The portable automatic detection device for alkylphenol pollutants in water according to claim 3, characterized in that, The injection valve (18) includes a second valve body, a second stator located inside the second valve body, and a second rotor rotating around the outer circumference of the second stator.

5. The portable automatic detection device for alkylphenol pollutants in water according to claim 4, characterized in that, The selector valve (3) and the injection valve (18) are both made of stainless steel or polyether ether ketone.

6. The portable in-situ alkylphenol contaminant measurement device of claim 1, wherein, The column oven (20) has heating elements for heating and thermocouples for temperature detection.

7. The portable in-situ alkylphenol contaminant measurement device of claim 1, wherein, It also includes a battery (23) for power supply.

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