Ion chromatography eluent on-line control system and method

Abstract

The present application relates to the technical field of ion chromatography eluent regulation, and particularly relates to an ion chromatography eluent online regulation system and method, wherein a multi-source eluent generation unit, a dynamic mixing and gradient regulation unit, a feedback control unit and a multi-system switching unit are arranged, the actual detection signal in the chromatographic separation process is actively adjusted to eluent, dynamic closed-loop regulation of the eluent components and concentration is realized, automatic switching between different eluent systems and automatic cleaning before switching can be realized, manual intervention is not needed, tedious processes and pollution risks caused by manual operation are effectively avoided, and the adaptability and continuous operation efficiency of different detection tasks are improved.

Description

Technical Field

[0001] This invention relates to the field of ion chromatography eluent control technology, specifically to an online control system and method for ion chromatography eluents. Background Technology

[0002] Eluent is the core medium for ion chromatography separation. Its composition, concentration, pH value, and gradient precision directly determine the chromatographic separation effect, retention time stability, and detection reproducibility. With the increasingly widespread application of ion chromatography in the analysis of complex matrix samples, higher requirements are placed on the flexibility, accuracy, and intelligence of eluent control.

[0003] However, traditional eluent concentration gradients use a preset open-loop control program, which cannot be adjusted in real time according to the actual separation effect or detection signal. When the sample matrix fluctuates or the column condition changes, the preset gradient is difficult to adapt, resulting in decreased resolution and retention time drift. Automatic eluent generators are single and cannot dynamically adjust the eluent composition ratio according to the elution requirements of different ions during the separation process, which limits the separation of complex samples. When it is necessary to switch to different eluent systems, existing systems require manual replacement of eluent storage tanks and manual cleaning of pipelines, which is cumbersome, time-consuming, and prone to introducing contamination. Therefore, the current reliability of ion chromatography eluent control is low and cannot meet the actual needs of use. Summary of the Invention

[0004] The purpose of this invention is to provide an online control system and method for ion chromatography eluent, thereby solving the technical problem of low reliability in the control of ion chromatography eluents.

[0005] The solution of the present invention to the above-mentioned technical problems is as follows: An online control system for ion chromatography eluent, comprising: A multi-source eluent generation unit includes at least two eluent components; A dynamic mixing and gradient adjustment unit is connected to the multi-source eluent generation unit and is used to mix the eluent components in proportion according to the detection requirements, adjust their concentration gradient, and generate eluent. The feedback control unit is connected to the chromatographic detector and the dynamic mixing and gradient adjustment unit, respectively, and is used to acquire the detection signal output by the chromatographic detector and adjust the eluent components or concentration when the detection signal is abnormal. The multi-system switching unit is used to switch between different rinsing fluid systems and to clean the flow path of the rinsing fluid before switching systems.

[0006] Furthermore, the online control system for ion chromatography eluent also includes: The prediction and optimization module has a built-in machine learning model, which is used to predict the initial parameters of the eluent based on historical detection data and column status, and send them as feedforward values ​​to the dynamic mixing and gradient adjustment unit.

[0007] Furthermore, the prediction optimization module incorporates a random forest or reinforcement learning algorithm to generate initial parameters for the eluent based on sample type, column usage frequency, historical eluent parameters, and separation performance score.

[0008] Further specifying, the multi-source rinsing solution generating unit includes an alkaline rinsing solution tank, an acidic rinsing solution tank, a pure water tank, and an additive tank. Each of the alkaline rinsing solution tank, acidic rinsing solution tank, pure water tank, and additive tank is equipped with a metering pump and a flow sensor. The metering pump and flow sensor are all connected to the dynamic mixing and gradient adjustment unit.

[0009] Furthermore, the feedback control unit is configured to establish a mapping model between the detection signal and the eluent parameters; When the chromatographic peak width is detected to exceed the preset threshold, the eluent concentration is adjusted according to the peak width change trend. When the resolution of adjacent chromatographic peaks is detected to be lower than the set value, reduce the gradient slope of the eluent or adjust the isocratic concentration of the eluent. When a retention time drift of more than ±2% is detected, if the retention time becomes longer, the concentration or flow rate of the rinsing solution is increased; if the retention time becomes shorter, the concentration or flow rate of the rinsing solution is decreased. When baseline noise or drift exceeds the limit, increase the proportion of pure water or decrease the proportion of additives in the rinsing solution.

[0010] Further defined, the multi-system switching unit includes an intelligent valve group and an automatic cleaning sub-unit connected to the intelligent valve group by a signal. The inlet of the intelligent valve group is connected to the cleaning liquid source and the multi-source rinsing liquid generation unit respectively, and the outlet of the intelligent valve group is connected to the dynamic mixing and gradient adjustment unit, which is used to connect the rinsing liquid component output by the multi-source rinsing liquid generation unit or the cleaning liquid in the cleaning liquid source to the dynamic mixing and gradient adjustment unit. The automatic cleaning subunit is configured to control the intelligent valve group to switch to the cleaning path before the rinsing fluid system is switched, and to control the intelligent valve group to switch to the multi-source rinsing fluid path after the rinsing fluid system is switched.

[0011] An online control method for ion chromatography eluent, based on the above-mentioned online control system for ion chromatography eluent, includes the following steps: According to the testing requirements, the components of each rinsing solution are mixed in proportion and their concentration gradient is adjusted to generate the rinsing solution. The obtained eluent is injected into an ion chromatography system for sample separation, and a detection signal is generated during the separation process using a chromatographic detector. Acquire the detection signal output by the chromatographic detector, and adjust the eluent components or concentration when the detection signal is abnormal; Automatic switching between multiple systems: When it is necessary to switch the rinsing solution system, the rinsing solution system is switched after the flow path cleaning is completed.

[0012] Furthermore, prior to the step of mixing the various eluent components in proportion according to the detection requirements, the following step is also included: Based on historical detection data and column status, the initial parameters of the eluent are predicted and sent as feedforward values ​​to the dynamic mixing and gradient adjustment unit.

[0013] Further specifying, the predicted initial parameters of the eluent are as follows: Initial parameters for the eluent are generated based on sample type, column usage count, historical eluent parameters, and separation performance score.

[0014] Further specifying, the adjustment of the eluent composition or concentration when the detection signal is abnormal includes the following steps: When the chromatographic peak width is detected to exceed the preset threshold, the eluent concentration is adjusted according to the peak width change trend. When the resolution of adjacent chromatographic peaks is detected to be lower than the set value, reduce the gradient slope of the eluent or adjust the isocratic concentration of the eluent. When a retention time drift of more than ±2% is detected, if the retention time becomes longer, the concentration or flow rate of the rinsing solution is increased; if the retention time becomes shorter, the concentration or flow rate of the rinsing solution is decreased. When baseline noise or drift exceeds the limit, increase the proportion of pure water or decrease the proportion of additives in the rinsing solution.

[0015] The beneficial effects of this invention are as follows: 1. This invention, by setting up a multi-source eluent generation unit, a dynamic mixing and gradient adjustment unit, a feedback control unit, and a multi-system switching unit, actively adjusts the eluent in case of abnormal detection signals during the chromatographic separation process, realizing dynamic closed-loop control of eluent components and concentration. At the same time, it can realize automatic switching between different eluent systems and automatic cleaning before switching, without manual intervention, effectively avoiding the cumbersome process and pollution risk caused by manual operation, and improving the adaptability and continuous operation efficiency of different detection tasks.

[0016] 2. This invention further introduces a predictive optimization module, which uses a machine learning model to predict the optimal initial parameters based on historical data and column status, and sends these parameters as feedforward values ​​to the dynamic mixing and gradient adjustment unit. This shortens the online control time of the eluent and improves the accuracy of the control. The eluent is adjusted for abnormal situations with different detection signals. Simultaneously, an automatic cleaning subunit switches between the eluent and cleaning solutions via an intelligent valve assembly. This not only ensures the flexibility and accuracy of the dynamic eluent ratio but also guarantees the thoroughness and reliability of the eluent system switching, thereby comprehensively enhancing the adaptability to complex sample analysis. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the online control method for ion chromatography eluent of the present invention. Detailed Implementation To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0018] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0019] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0020] Example 1 This invention provides an online control system for ion chromatography eluent, comprising: A multi-source eluent generation unit includes at least two eluent components; A dynamic mixing and gradient adjustment unit is connected to the multi-source eluent generation unit and is used to mix the eluent components in proportion according to the detection requirements, adjust their concentration gradient, and generate eluent. The feedback control unit is connected to the chromatographic detector and the dynamic mixing and gradient adjustment unit, respectively, and is used to acquire the detection signal output by the chromatographic detector and adjust the eluent components or concentration when the detection signal is abnormal. The multi-system switching unit is used to switch between different rinsing fluid systems and to clean the flow path of the rinsing fluid before switching systems.

[0021] Specifically, the multi-source rinsing fluid generation unit includes multiple independently controlled rinsing fluid sources. Each rinsing fluid source includes a storage tank for storing the corresponding rinsing fluid components, a metering pump connected to the storage tank, and a flow sensor. The metering pump can independently control the output of each component from the storage tank, and the flow sensor is used for flow confirmation and correction to ensure accurate and reliable control of the metering pump output, with a mixing accuracy of ±0.5%. Both the metering pump and the flow sensor are connected to the dynamic mixing and gradient adjustment unit, and mixing is performed according to the rinsing fluid parameters obtained from the dynamic mixing and gradient adjustment unit.

[0022] The storage tanks include, for example, an alkaline rinsing solution tank, an acidic rinsing solution tank, a pure water tank, and an additive tank. The alkaline rinsing solution tank contains, for example, KOH or NaOH solution, the acidic rinsing solution tank contains, for example, HNO3 or H2SO4 solution, and the additive tank contains, for example, an organic solvent or a complexing agent.

[0023] Preferably, in order to improve the control efficiency of the eluent, the online control system for ion chromatography eluent provided in this embodiment also includes a prediction and optimization module with a built-in machine learning model, which is used to predict the initial parameters of the eluent based on historical detection data and column status, and send them as feedforward values ​​to the dynamic mixing and gradient adjustment unit.

[0024] Specifically, the prediction and optimization module incorporates random forest or reinforcement learning algorithms to continuously record historical detection data, such as sample type, column usage frequency, eluent parameters, and separation performance scores. A machine learning algorithm is used to establish a correlation model between separation performance and eluent parameters. This allows the module to predict initial eluent parameters, such as concentration, component ratio, and pH, based on the current column status and sample characteristics before each ion chromatography detection. These initial parameters are then sent as feedforward setpoints to the dynamic mixing and gradient control unit, enabling the unit to control the metering pump on the corresponding storage tank to prepare the eluent. The metering pump employs a dual-plunger tandem structure, achieving a flow rate accuracy of ±0.1%.

[0025] To further explain, the dynamic mixing and gradient adjustment unit includes a static mixer, a concentration sensor, a pH sensor, and a multi-channel switching valve assembly. The multi-channel switching valve assembly is used to draw liquid from a designated storage tank into the static mixer for mixing. In conjunction with the concentration sensor and pH sensor, the concentration and pH of the mixed eluent are monitored in real time, realizing the dynamic proportioning and concentration gradient generation of the eluent, ensuring the efficient and reliable preparation of the eluent.

[0026] First, the eluent prepared according to the initial eluent parameters is injected into the ion chromatography separation system to elute and separate the sample. The output signal is acquired in real time using a chromatographic detector, such as a conductivity detector and a mass spectrometer to acquire conductivity and response values. The acquired detection signal is then input to the feedback control unit.

[0027] The feedback control unit is configured to establish a mapping model between the detection signal and the eluent parameters. When the detection signal shows abnormal fluctuations, such as an increase in peak width, a decrease in separation, or baseline drift, the feedback control unit automatically determines whether the current eluent concentration deviates from the optimal value. If so, it adjusts the parameters of the dynamic mixing and gradient adjustment unit in conjunction with the preset separation target to achieve real-time closed-loop correction of the eluent concentration.

[0028] Specifically, when the chromatographic peak width is detected to exceed a preset threshold, the eluent concentration is adjusted according to the peak width change trend; When the resolution of adjacent chromatographic peaks is detected to be lower than the set value, reduce the gradient slope of the eluent or adjust the isocratic concentration of the eluent. When a retention time drift of more than ±2% is detected, if the retention time becomes longer, the concentration or flow rate of the rinsing solution is increased; if the retention time becomes shorter, the concentration or flow rate of the rinsing solution is decreased. When baseline noise or drift exceeds the limit, increase the proportion of pure water or decrease the proportion of additives in the rinsing solution.

[0029] To further explain, for the separation requirements of ions with different properties in complex samples, the feedback control unit can dynamically adjust the proportion of each component in the eluent according to the types of ions eluted at different time points during the chromatographic separation process; for example: When separating strongly retained ions, the proportion of organic solvents such as acetonitrile or methanol is automatically increased to enhance elution capacity; When separating easily hydrolyzable ions, the pH value is automatically adjusted to inhibit ion hydrolysis; When separating transition metal ions, a complexing agent is automatically added to improve peak shape.

[0030] The proportion of each component in the eluent is dynamically adjusted using a model predictive control algorithm to predict the elution window in advance and achieve feedforward-feedback composite control of the component proportion. At this time, the feedback control unit adopts a strategy that combines PID control and model predictive control (MPC) to balance response speed and control accuracy.

[0031] To further explain, when the detection requirement necessitates switching between different eluent systems, such as switching from anion detection to cation detection, or switching from a conventional system to a dedicated system, a multi-system switching unit can be used to switch the eluent system.

[0032] The multi-system switching unit includes an intelligent valve group and an automatic cleaning subunit connected to the intelligent valve group via signals. The inlet of the intelligent valve group is connected to the cleaning fluid source and the multi-source rinsing fluid generation unit, respectively. The outlet of the intelligent valve group is connected to the dynamic mixing and gradient adjustment unit, which is used to connect the rinsing fluid components output by the multi-source rinsing fluid generation unit or the cleaning fluid in the cleaning fluid source to the dynamic mixing and gradient adjustment unit for rinsing fluid mixing and preparation or internal pipeline cleaning. The cleaning fluid source can be pure water in a pure water tank.

[0033] The automatic cleaning subunit is configured to control the intelligent valve group to switch to the cleaning path before the rinsing fluid system is switched, and use pure water to clean the internal pipeline, while simultaneously cleaning the static mixer and each sensor in the pipeline; after the rinsing fluid system is switched, the intelligent valve group is controlled to switch to the multi-source rinsing fluid path, and the initial parameters of the rinsing fluid under the current system are solved according to the detection requirements and the corresponding rinsing fluid is prepared.

[0034] Example 2 refer to Figure 1 Based on the online control system for ion chromatography eluent provided in Example 1, this example provides an online control method for ion chromatography eluent, comprising the following steps: Based on historical detection data and column status, the initial parameters of the eluent are predicted and sent as feedforward values ​​to the dynamic mixing and gradient control unit. According to the testing requirements, the components of each rinsing solution are mixed in proportion and their concentration gradient is adjusted to generate the rinsing solution. The obtained eluent is injected into an ion chromatography system for sample separation, and a detection signal is generated during the separation process using a chromatographic detector. Acquire the detection signal output by the chromatographic detector, and adjust the eluent components or concentration when the detection signal is abnormal; Automatic switching between multiple systems: When it is necessary to switch the rinsing solution system, the rinsing solution system is switched after the flow path cleaning is completed.

[0035] To further explain, the specific initial parameters of the predicted eluent are as follows: Initial parameters for the eluent are generated based on sample type, column usage count, historical eluent parameters, and separation performance score.

[0036] To further explain, adjusting the eluent composition or concentration when an abnormal detection signal occurs includes the following steps: When the chromatographic peak width is detected to exceed the preset threshold, the eluent concentration is adjusted according to the peak width change trend. When the resolution of adjacent chromatographic peaks is detected to be lower than the set value, reduce the gradient slope of the eluent or adjust the isocratic concentration of the eluent. When a retention time drift of more than ±2% is detected, if the retention time becomes longer, the concentration or flow rate of the rinsing solution is increased; if the retention time becomes shorter, the concentration or flow rate of the rinsing solution is decreased. When baseline noise or drift exceeds the limit, increase the proportion of pure water or decrease the proportion of additives in the rinsing solution.

[0037] The first implementation process involves a high concentration of Cl... - SO4² - Anion detection was performed on industrial wastewater containing organic pollutants. Based on the sample information and column status, the prediction and optimization module obtained the initial parameters of the eluent as follows: KOH concentration 0.05 mol / L, flow rate 1.0 mL / min, and isocratic elution.

[0038] The dynamic mixing and gradient adjustment unit prepares the eluent according to the initial parameters of the eluent and then performs testing.

[0039] When the detection reached the 6th minute, the feedback control unit detected Cl. - The peak width increased abnormally, exceeding the set threshold by 15%, which was determined to be insufficient elution strength. The KOH concentration was dynamically increased to 0.07 mol / L, and the peak width returned to normal within 30 seconds.

[0040] SO4² in the 10th-14th minute - During the elution stage, the feedback control unit detected peak tailing and needed to add 5% acetonitrile to the eluent to improve peak symmetry. Subsequently, the tailing factor decreased from 1.5 to 1.1.

[0041] The final resolution R≥2.0, retention time RSD=0.25%, and the accuracy of the detection results improved by 25%.

[0042] The second implementation process involves continuously analyzing anions F in water samples. - Cl - and SO4² - With cation Na + K + and Mg² + Detection: If the first real-time process is completed, the rinsing solution system needs to be switched. At this time, the automatic cleaning subunit controls the intelligent valve group to switch to the cleaning path and clean for 3 minutes, so that the conductivity monitored by the concentration sensor drops to below 1μS / cm.

[0043] Subsequently, the automatic cleaning subunit controls the intelligent valve group to switch to the multi-source rinsing solution path, preparing to start cation detection.

[0044] Similarly, the initial parameters of the eluent for cation detection are first determined and the corresponding HNO3 eluent is prepared. After the pH sensor confirms that the pH value is stable at 2.5±0.1 and the background conductivity is stable, cation detection is automatically started. No manual intervention is required throughout the process. The total switching time is 4 minutes and 20 seconds, which is more than 60% more efficient than the traditional manual switching.

[0045] The third implementation process involves testing the retention time stability of the chromatographic column after 100 consecutive runs: During the 95th test, the feedback control unit detected F - The retention time drifted by +4.2% from the initial value, exceeding the set threshold of ±2%. At this point, the column aging caused a decrease in retention capacity. The feedback control unit dynamically adjusted the eluent concentration, gradually increasing the KOH concentration from 0.05 mol / L to 0.058 mol / L. After adjustment, the retention time recovered to within ±1% of the initial value in the 96th detection. At this point, the current eluent adjustment parameters were recorded and the correlation model between the separation effect and the eluent parameters in the prediction and optimization module was updated.

[0046] Compared to traditional open-loop control, it achieves adaptive calibration, effectively extending the effective lifespan of the chromatographic column by approximately 40%.

[0047] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0048] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

[0049] 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 or all of the technical features; and these 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 online control system for ion chromatography eluent, characterized in that, include: A multi-source eluent generation unit includes at least two eluent components; A dynamic mixing and gradient adjustment unit is connected to the multi-source eluent generation unit and is used to mix the eluent components in proportion according to the detection requirements, adjust their concentration gradient, and generate eluent. The feedback control unit is connected to the chromatographic detector and the dynamic mixing and gradient adjustment unit, respectively, and is used to acquire the detection signal output by the chromatographic detector and adjust the eluent components or concentration when the detection signal is abnormal. The multi-system switching unit is used to switch between different rinsing fluid systems and to clean the flow path of the rinsing fluid before switching systems.

2. The online control system for ion chromatography eluent according to claim 1, characterized in that, The online control system for ion chromatography eluent also includes: The prediction and optimization module has a built-in machine learning model, which is used to predict the initial parameters of the eluent based on historical detection data and column status, and send them as feedforward values ​​to the dynamic mixing and gradient adjustment unit.

3. The online control system for ion chromatography eluent according to claim 2, characterized in that, The prediction and optimization module incorporates a random forest or reinforcement learning algorithm to generate initial parameters for the eluent based on sample type, column usage count, historical eluent parameters, and separation performance score.

4. The online control system for ion chromatography eluent according to claim 1, characterized in that, The multi-source rinsing solution generating unit includes an alkaline rinsing solution tank, an acidic rinsing solution tank, a pure water tank, and an additive tank. Each of the alkaline rinsing solution tank, acidic rinsing solution tank, pure water tank, and additive tank is equipped with a metering pump and a flow sensor. The metering pump and flow sensor are all connected to the dynamic mixing and gradient adjustment unit.

5. The online control system for ion chromatography eluent according to claim 1, characterized in that, The feedback control unit is configured to establish a mapping model between the detection signal and the parameters of the rinsing solution. When the chromatographic peak width is detected to exceed the preset threshold, the eluent concentration is adjusted according to the peak width change trend. When the resolution of adjacent chromatographic peaks is detected to be lower than the set value, reduce the gradient slope of the eluent or adjust the isocratic concentration of the eluent. When a retention time drift of more than ±2% is detected, if the retention time becomes longer, the concentration or flow rate of the rinsing solution is increased; if the retention time becomes shorter, the concentration or flow rate of the rinsing solution is decreased. When baseline noise or drift exceeds the limit, increase the proportion of pure water or decrease the proportion of additives in the rinsing solution.

6. The online control system for ion chromatography eluent according to claim 1, characterized in that, The multi-system switching unit includes an intelligent valve group and an automatic cleaning sub-unit connected to the intelligent valve group via a signal. The inlet of the intelligent valve group is connected to the cleaning fluid source and the multi-source rinsing fluid generation unit, respectively. The outlet of the intelligent valve group is connected to the dynamic mixing and gradient adjustment unit, which is used to connect the rinsing fluid components output by the multi-source rinsing fluid generation unit or the cleaning fluid in the cleaning fluid source to the dynamic mixing and gradient adjustment unit. The automatic cleaning subunit is configured to control the intelligent valve group to switch to the cleaning path before the rinsing fluid system is switched, and to control the intelligent valve group to switch to the multi-source rinsing fluid path after the rinsing fluid system is switched.

7. A method for online control of ion chromatography eluent, characterized in that, The online control system for ion chromatography eluent according to any one of claims 1 to 6 includes the following steps: According to the testing requirements, the components of each rinsing solution are mixed in proportion and their concentration gradient is adjusted to generate the rinsing solution. The obtained eluent is injected into an ion chromatography system for sample separation, and a detection signal is generated during the separation process using a chromatographic detector. Acquire the detection signal output by the chromatographic detector, and adjust the eluent components or concentration when the detection signal is abnormal; Automatic switching between multiple systems: When it is necessary to switch the rinsing solution system, the rinsing solution system is switched after the flow path cleaning is completed.

8. The online control method for ion chromatography eluent according to claim 7, characterized in that, Before the step of mixing the various eluent components in proportion according to the detection requirements, the following steps are also included: Based on historical detection data and column status, the initial parameters of the eluent are predicted and sent as feedforward values ​​to the dynamic mixing and gradient adjustment unit.

9. The online control method for ion chromatography eluent according to claim 8, characterized in that, The specific initial parameters of the predicted eluent are as follows: Initial parameters for the eluent are generated based on sample type, column usage count, historical eluent parameters, and separation performance score.

10. The method for online control of ion chromatography eluent according to claim 7, characterized in that, The step of adjusting the eluent composition or concentration when an abnormal detection signal is detected includes the following steps: When the chromatographic peak width is detected to exceed the preset threshold, the eluent concentration is adjusted according to the peak width change trend. When the resolution of adjacent chromatographic peaks is detected to be lower than the set value, reduce the gradient slope of the eluent or adjust the isocratic concentration of the eluent. When a retention time drift of more than ±2% is detected, if the retention time becomes longer, the concentration or flow rate of the rinsing solution is increased; if the retention time becomes shorter, the concentration or flow rate of the rinsing solution is decreased. When baseline noise or drift exceeds the limit, increase the proportion of pure water or decrease the proportion of additives in the rinsing solution.

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