Electronic grade triethyl borate gas chromatography purity analysis system

Abstract

The invention relates to the technical field of gas chromatography, in particular to a gas chromatography purity analysis system for electronic grade triethyl borate. According to the method, accurate and stable adjustment of the temperature, the speed and the flow of a sample inlet is ensured through an accurate sample injection amount and sample injection speed control model and a fuzzy PID control algorithm, and interference of temperature fluctuation on the gasification and separation process of triethyl borate is avoided; a high-precision chromatographic column separation technology and optimized flow velocity control are adopted, and a separation degree factor and the retention time of a chromatographic peak are accurately calculated, so that full separation of each component is ensured, and the resolution of impurity analysis is remarkably improved. And through noise reduction processing and wavelet transformation, the system effectively removes high-frequency noise in the signal, the recognizable degree of the target signal is enhanced, and the reliability of quantitative analysis is improved. Meanwhile, the control feedback module performs automatic adjustment according to the noise reduction demand characteristic value, and optimizes the sample introduction process to realize the optimal analysis effect.

Description

Technical Field

[0001] This invention relates to the field of gas chromatography analysis technology, specifically to a gas chromatography purity analysis system for electronic-grade triethyl borate. Background Technology

[0002] Gas chromatography (GC) is a commonly used analytical technique widely applied in the field of chemical analysis, particularly in the quantitative and qualitative analysis of the composition of gaseous, liquid, and solid compounds. The accuracy and stability of GC analysis are affected by various factors, among which injection volume, temperature control, column separation efficiency, and the sensitivity of the signal detection system are crucial factors influencing the analytical results.

[0003] In gas chromatography analysis, injection port temperature control is particularly important because for heat-sensitive compounds such as triethyl borate, even small temperature fluctuations can lead to incomplete sample vaporization, peak tailing, fragmentation, or pyrolysis, ultimately affecting separation efficiency and the accuracy of purity detection. Traditional PID (Proportional-Integral-Derivative) control algorithms are commonly used to control injection port temperature; however, because their parameters are fixed, they cannot flexibly respond to dynamic disturbances caused by temperature changes, resulting in problems such as temperature control lag and overshoot.

[0004] To address the aforementioned issues, it is necessary to propose a gas chromatographic purity analysis system for electronic-grade triethyl borate. Summary of the Invention

[0005] The purpose of this invention is to solve the problems existing in the background art and to propose an electronic-grade triethyl borate gas chromatography purity analysis system.

[0006] The objective of this invention can be achieved through the following technical solutions: An electronic-grade triethyl borate gas chromatography purity analysis system includes a gas chromatography sampling and injection module, a chromatographic column separation module, a signal detection and data acquisition module, a data processing and analysis module, and a control feedback module.

[0007] The gas chromatography sampling and injection module uses a stepper motor and valves to drive triethyl borate into the autosampler, establishing a control model for injection volume and injection speed. During injection, the injection port temperature is controlled to avoid interference from temperature fluctuations on the detection results.

[0008] The inner diameter of the injection needle, injection time, total number of steps of the stepper motor, and piston displacement corresponding to each step of the motor are obtained for the triethyl borate autosampler. An injection volume model and an injection speed model are constructed to describe their mathematical relationship with the injection volume and injection speed.

[0009] Furthermore, triethyl borate is driven into the autosampler by a stepper motor and valves, and the injection time, the total number of steps of the stepper motor, and the piston displacement corresponding to each step of the motor are set to the initial preset values.

[0010] During the injection process, the temperature error between the injection port temperature and the preset injection temperature is acquired in real time.

[0011] Furthermore, the temperature error is analyzed using a fuzzy PID control algorithm to calculate the temperature control quantity and adjust the injection port temperature accordingly. The specific process is as follows: At preset time intervals, the rate of change of temperature error is calculated, and fuzzification is performed based on the temperature error and its rate of change. The fundamental universes of discourse are obtained, including the fundamental universe of discourse for temperature error and the fundamental universe of discourse for the rate of change of temperature error, i.e., the data distribution range. The quantization factor and quantization value of the temperature error are calculated based on the quantization domain, and the quantization factor and quantization value of the temperature change rate error are also calculated based on the quantization domain.

[0012] The proportional gain, derivative gain, and integral gain corrections are matched based on the quantized values ​​of temperature error and temperature change rate error. The proportional gain, derivative gain, and integral gain of the PID control are then adjusted in real time based on these corrections.

[0013] Set upper and lower limits for proportional gain, derivative gain, and integral gain in real-time adjustment to prevent integral saturation or runaway.

[0014] The system acquires the proportional gain, derivative gain, and integral gain at the current moment, calculates the real-time PWM duty cycle adjustment value for the injection port temperature, and sends it to the injection port temperature adjustment module to perform temperature adjustment.

[0015] The column separation module optimizes the gas sample flow rate and performs column separation using the gas sample retention time versus temperature curve. It separates different components in the gas sample by controlling the stationary phase, optimizes the chromatographic peak resolution, and calculates the resolution factor.

[0016] The carrier gas flow rate of the gas sample is calculated using the van der Munte equation.

[0017] Furthermore, the temperature relationship curve is calculated, the retention time of the gas sample in the stationary phase is controlled, and column separation is performed. The specific process is as follows: Calculate the retention time of the gas sample in the stationary phase; Access the chromatographic column with methyl polysiloxane as the stationary phase, obtain the baseline length of the chromatographic peaks in the column corresponding to each component, and calculate the resolution factor between any two adjacent chromatographic peaks and their corresponding components.

[0018] Access the flame photometric detector to capture the characteristic spectrum generated when free radicals produced by electronic-grade triethyl borate in a hydrogen-rich flame transition from the excited state back to the ground state. Then, convert the intensity of the flame photometric detector into an electrical signal and send it to the data processing and analysis module.

[0019] The signal detection and data acquisition module acquires the concentration data of the separated electronic-grade triethyl borate and its byproducts, and converts them into chromatographic column data.

[0020] The data processing and analysis module performs noise removal and smoothing on the collected concentration data of electronic-grade triethyl borate and its byproducts, and calculates the noise reduction requirement characteristic value. The component content of each element in the sample is calculated and analyzed using the peak area calculation method to obtain the concentration data of electronic-grade triethyl borate and each byproduct, including the characteristic values ​​of the main peak area ratio and the main peak retention time ratio.

[0021] Wavelet transform is used to denoise the electrical signal, filtering out the high-frequency components and retaining the low-frequency components. The energy spectral density of the high-frequency and low-frequency components is calculated. The characteristic value required for denoising is obtained by calculating the difference between the energy spectral densities of the high-frequency and low-frequency components.

[0022] Furthermore, the retention times and peak areas of each chromatographic peak are obtained in the low-frequency range. The retention time and peak area of ​​the main peak corresponding to triethyl borate are obtained, and the characteristic values ​​of the main peak area ratio and retention time ratio are calculated.

[0023] The control feedback module adjusts the injection volume and injection speed of the autosampler based on the noise reduction requirement characteristics. The adjusted injection volume and speed are sent to the control model for these parameters, along with the total number of steps of the reverse-propulsion stepper motor and the piston displacement corresponding to each step, which are then sent to the forward-propulsion motor. The purity of the triethyl borate product is determined based on the resolution factor, the concentration data of electronic-grade triethyl borate, and the concentrations of various byproducts.

[0024] If the noise reduction requirement value exceeds the preset threshold, it is determined that the gas chromatographic purity data for triethyl borate has excessive noise, and the injection volume and injection speed of the autosampler should be reduced. The injection volume and injection speed are adjusted to 50% of the current values ​​and sent to the gas chromatographic sampling and injection module. Based on the injection volume model and injection speed model, the injection time, the total number of steps of the advance motor, and the piston displacement corresponding to each step of the motor are reversed.

[0025] Furthermore, the concentration of triethyl borate product was determined using the separation factor, electronic grade triethyl borate, and concentration data of each byproduct. The specific process is as follows: If both the peak area ratio and retention time ratio are greater than their preset thresholds, and the resolution factor between any two adjacent peaks is greater than the preset threshold, then it is determined that electronic-grade triethyl borate and its reaction byproducts (ethanol, boric anhydride, organic solvent), hydrolysis byproducts (boric acid, ethanol, water), and reaction byproducts (organoborate ester polymers, cyclic compounds, or complex derivatives of boric acid) are sufficiently separated, and the concentration ratio of triethyl borate in the gas sample meets the standard. The peak area ratio characteristic value is then output as the detection concentration of triethyl borate. Otherwise, the concentration ratio of triethyl borate in the gas sample is determined to be insufficient.

[0026] Compared with the prior art, the beneficial effects of the present invention are: This invention utilizes a precise injection volume and injection rate control model, combined with real-time temperature error feedback and a fuzzy PID control algorithm, to ensure accurate and stable adjustment of the injection port temperature. This effectively avoids the interference of temperature fluctuations on the vaporization and separation process of triethyl borate, thereby improving the accuracy of analytical results. Employing high-precision chromatographic column separation technology and optimized flow rate control, and precisely calculating the resolution factor and retention time of chromatographic peaks, it ensures thorough separation of each component, significantly improving the resolution of impurity analysis. Through noise reduction processing and wavelet transform, the system effectively removes high-frequency noise from the signal, enhancing the discernibility of the target signal and improving the reliability of quantitative analysis. Simultaneously, the control feedback module automatically adjusts based on the noise reduction requirement characteristics, optimizing the injection process to achieve the best analytical results. Attached Figure Description

[0027] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings: Figure 1 This is a system block diagram of the present invention. Detailed Implementation

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Please see Figure 1 As shown, an electronic-grade triethyl borate gas chromatography purity analysis system includes a gas chromatography sampling and injection module, a chromatographic column separation module, a signal detection and data acquisition module, a data processing and analysis module, and a control feedback module.

[0030] The gas chromatography sampling and injection module uses a stepper motor and valves to drive triethyl borate into the autosampler, establishing a control model for injection volume and injection speed. During injection, the injection port temperature is controlled to avoid interference from temperature fluctuations on the detection results.

[0031] Obtain the inner diameter of the injection needle of the triethyl borate autosampler Injection time Total number of steps of the progressive motor The piston displacement corresponding to each step of the motor Construct injection volume model and injection rate model: in This is the injection volume. This refers to the injection speed.

[0032] Furthermore, triethyl borate is driven into the autosampler via a progressive motor and valve, and the injection time is set. Total number of steps of the progressive motor The piston displacement corresponding to each step of the motor These are the initial preset values.

[0033] During the injection process, the temperature at the injection port is acquired in real time. With preset injection temperature Temperature error Where t represents the data acquisition time, and the preset injection temperature is... The specific value is 280℃.

[0034] Furthermore, the temperature error e(t) is analyzed using a fuzzy PID control algorithm to calculate the temperature control quantity and provide feedback adjustment to the injection port temperature. The specific process is as follows: Calculate the rate of change of temperature error e(t) at preset time intervals: Fuzzification is performed based on the temperature error e(t) and its rate of change ec(t). The fundamental universes of discourse are obtained, including the fundamental universe of discourse for the temperature error and the fundamental universe of discourse for the rate of change of the temperature error, i.e., the data distribution range. The fundamental universe of discourse for the temperature error is [-5℃, 5℃], representing the tolerance of ±5℃ temperature error for fuzzy PID control; the fundamental universe of discourse for the rate of change of the temperature error is [-1℃ / s, 1℃ / s], representing the tolerance of ±1℃ temperature change error per second for fuzzy PID control.

[0035] Calculate the quantization factor Ke and quantization value Ee of the temperature error e(t) based on the quantization domain: The quantization factor Kec and quantization value Eec of the temperature change rate error ec(t) are calculated based on the quantization domain: The round operator is used for rounding. The numerical ranges of the temperature error quantization value Ec and the temperature change rate error quantization value Eec are both {-2, -1, 0, 1, 2}.

[0036] Based on the quantized value of temperature error Ec and the quantized value of temperature change rate error Eec, the correction amounts ΔKp, ΔKi, and ΔKd of the proportional gain, the matching relationship is as follows: The proportional gain, derivative gain, and integral gain of the PID control are adjusted in real time based on the corrections ΔKp, ΔKi, and ΔKd for the proportional gain, derivative gain, and integral gain. The adjustment formula is as follows: Among them , and These are the proportional gain, differential gain, and integral gain at the current time t, respectively. Among them , and These represent the proportional gain, differential gain, and integral gain at the previous time t-1, respectively.

[0037] Set the upper and lower limits for proportional gain, derivative gain, and integral gain in real-time adjustment: , and To prevent integral saturation or runaway.

[0038] Obtain the proportional gain, derivative gain, and integral gain at the current time. , and By using a preset formula: The real-time PWM duty cycle adjustment value u(t) of the injection port temperature is calculated and sent to the injection port temperature adjustment module to perform temperature adjustment.

[0039] It should be noted that triethyl borate is extremely sensitive to temperature changes. Excessively high injection port temperature may cause partial thermal decomposition of triethyl borate, generating new impurity peaks and resulting in lower purity detection values. Conversely, excessively low temperature may lead to incomplete sample vaporization, causing peak tailing or splitting, reducing quantitative accuracy. Furthermore, inaccurate temperature ramp-up rates in the column oven can directly deteriorate the resolution of key impurity pairs, and may even lead to co-elution, rendering the qualitative and quantitative analysis of trace impurities ineffective. Ultimately, this will fail to meet the precise requirements for ultra-high purity detection of electronic-grade chemicals.

[0040] It should be further explained that traditional PID control uses fixed proportional parameters. However, triethyl borate, as a heat-sensitive compound, places far more stringent demands on the accuracy and stability of temperature control for gas chromatographic purity analysis than for conventional samples. During the instantaneous vaporization at the injection port and the programmed temperature rise separation process on the column, even minute temperature fluctuations directly affect not only the vaporization efficiency and chromatographic behavior of triethyl borate itself, but also significantly impact its separation from key byproducts (such as diethyl borate and ethanol). If a traditional PID control algorithm is used, its reliance on fixed control parameters makes it difficult to effectively handle nonlinear and time-varying disturbances such as drastic changes in heat load during injection, cooling effects caused by changes in carrier gas flow rate, and fluctuations in ambient temperature, leading to overshoot or lag in temperature control.

[0041] The column separation module optimizes the gas sample flow rate and performs column separation using the gas sample retention time versus temperature curve. It separates different components in the gas sample by controlling the stationary phase, optimizes the chromatographic peak resolution, and calculates the resolution factor.

[0042] By the van Dimme equation: Calculate the carrier gas velocity HETP of the gas sample. Here, u is the linear velocity of the carrier gas in the gas sample; A is a preset eddy diffusion term, representing the stationary phase particle size and filling uniformity, with a preset value of 0; B is a preset molecular diffusion term; and C is a preset mass transfer resistance term.

[0043] Furthermore, the temperature relationship curve is calculated, the retention time of the gas sample in the stationary phase is controlled, and column separation is performed. The specific process is as follows: By using a preset formula: Calculate the retention time of the gas sample in the stationary phase. ; Where k is the capacity factor, and These represent the retention time of the gas sample in the stationary phase and the preset over-limit time, respectively, where R is the preset ideal gas constant and T is the Kelvin temperature of the gas sample; β represents the adsorption / dissolution entropy change of the solute on the stationary phase; where β is the volume ratio of the gas phase to the stationary phase in the chromatographic column.

[0044] Access a chromatographic column with a stationary phase of methylpolysiloxane. The stationary phase has a length × inner diameter × film thickness specification of 0m × 0.32mm × 1.0μm. Obtain the baseline length Wi of the chromatographic peaks corresponding to each component in the chromatographic column, where i is the chromatographic peak sequence number, i=1, 2, ..., n; n is the total number of chromatographic peaks. By using a preset formula: Calculate the resolution factor between the components corresponding to any two adjacent chromatographic peaks i and i+1. Among them and These represent the retention times of the components corresponding to any two adjacent chromatographic peaks i and i+1, respectively.

[0045] It should be noted that a higher separation factor indicates a more thorough separation of the two adjacent components.

[0046] The signal detection and data acquisition module accesses the flame photometric detector to obtain the concentration of electronic-grade triethyl borate and its byproducts, and converts their respective gas chromatographic concentration data into electrical signals, which are then sent to the data processing and analysis module.

[0047] Access the flame photometric detector to capture the characteristic spectrum (545nm wavelength) of free radicals generated by electronic-grade triethyl borate in a hydrogen-rich flame environment when they transition from the excited state back to the ground state. The intensity of the flame photometric detector is then converted into an electrical signal I and sent to the data processing and analysis module.

[0048] The data processing and analysis module performs noise removal and smoothing on the collected concentration data of electronic-grade triethyl borate and its byproducts, and calculates the noise reduction requirement characteristic value. The component content of each element in the sample is calculated and analyzed using the peak area calculation method to obtain the concentration data of electronic-grade triethyl borate and each byproduct, including the characteristic values ​​of the main peak area ratio and the main peak retention time ratio.

[0049] The electrical signal I is denoised using wavelet transform, filtering out the high-frequency component Da and retaining the low-frequency component De. The energy spectral density P(Da) of the high-frequency component and the energy spectral density P(De) of the low-frequency component are calculated. The denoising requirement characteristic value E(a / e) is obtained by calculating the difference between the energy spectral densities of the high-frequency and low-frequency components.

[0050] It should be noted that the noise reduction requirement eigenvalue quantifies the relative intensity ratio of noise to effective signal in the original signal. A larger eigenvalue indicates a stronger energy spectral density (ESD) in the high-frequency region compared to the low-frequency region, meaning a higher proportion of invalid information such as random noise and spike interference in the signal. Therefore, the urgency and intensity of noise reduction processing are also higher. Specifically, in terms of spectral components, the high-frequency region typically corresponds to random noise, baseline spikes, and rapid transient interference in the signal. These components can mask the true chromatographic peak shape, affecting the accurate determination of peak start and end points. The low-frequency region, on the other hand, carries the core characteristics of the signal—the main body of chromatographic peaks with a certain width and smooth variation, generated by the target analyte and impurity components—which forms the basis for subsequent qualitative and quantitative analysis.

[0051] Furthermore, in the low-frequency region De, the retention times ti and peak areas Ai of each chromatographic peak are obtained. The retention time of the main peak corresponding to triethyl borate is also obtained. and chromatographic peak area .

[0052] By using a preset formula: Calculate the characteristic value C1 of the main peak area ratio and the characteristic value C2 of the main peak retention time ratio.

[0053] The control feedback module adjusts the injection volume and injection speed of the autosampler based on the noise reduction requirement characteristics. The adjusted injection volume and speed are sent to the control model for these parameters, along with the total number of steps of the reverse-propulsion stepper motor and the piston displacement corresponding to each step, which are then sent to the forward-propulsion motor. The purity of the triethyl borate product is determined based on the resolution factor, the concentration data of electronic-grade triethyl borate, and the concentrations of various byproducts.

[0054] If the noise reduction requirement value exceeds the preset threshold, the gas chromatographic purity data for triethyl borate is determined to have significant noise, and the injection volume and injection speed of the autosampler should be reduced. and injection rate Adjust the value to 50% of the current value and send it to the gas chromatography sampling and injection module. Based on the injection volume model and injection rate model, reverse the injection time. Total number of steps of the progressive motor The piston displacement corresponding to each step of the motor .

[0055] Furthermore, the concentration of triethyl borate product was determined using the separation factor, electronic grade triethyl borate, and concentration data of each byproduct. The specific process is as follows: If both the main peak area ratio characteristic value C1 and the main peak retention time ratio characteristic value C2 are greater than their own preset thresholds, and the resolution factor between the components corresponding to any two adjacent chromatographic peaks i and i+1 is greater than their own preset thresholds, then... If the concentration exceeds a preset threshold, it is determined that electronic-grade triethyl borate and its reaction byproducts (ethanol, boric anhydride, organic solvents), hydrolysis byproducts (boric acid, ethanol, water), and reaction byproducts (organoboroate polymers, cyclic compounds, or complex derivatives of boric acid) are sufficiently separated, and the concentration of triethyl borate within these byproducts meets the standard. The characteristic value of the main peak area ratio is then output as the detection concentration of triethyl borate. Otherwise, the concentration of triethyl borate in the gas sample is deemed insufficient.

[0056] It should be understood that the terms “comprising” and “including” used in this disclosure and claims indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0057] It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the disclosure. As used in this disclosure and claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this disclosure and claims means any combination and all possible combinations of one or more of the associated listed items, and includes such combinations; The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to any specific implementation. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A gas chromatographic purity analysis system for electronic-grade triethyl borate, comprising a gas chromatographic sampling and injection module, a chromatographic column separation module, a signal detection and data acquisition module, and a data processing and analysis module, characterized in that: The gas chromatography sampling and injection module drives triethyl borate into the autosampler via a stepper motor and valves, and establishes a control model for injection volume and injection speed; during the injection process, the injection port temperature is controlled to avoid interference from temperature fluctuations on the detection results; The column separation module optimizes the gas sample flow rate and performs column separation based on the relationship curve between gas sample retention time and temperature. It separates different components in the gas sample by controlling the stationary phase, optimizes the chromatographic peak resolution, and calculates the resolution factor. The signal detection and data acquisition module accesses the flame photometric detector to obtain the concentration of electronic grade triethyl borate and its byproducts, and converts their respective gas chromatographic concentration data into electrical signals, which are then sent to the data processing and analysis module. The data processing and analysis module performs noise removal and smoothing on the collected concentration data of electronic-grade triethyl borate and its byproducts, and calculates the noise reduction requirement characteristic value. The concentrations of each component in the sample were calculated and analyzed using the peak area calculation method, and the concentration data of electronic grade triethyl borate and each byproduct were obtained.

2. The electronic-grade triethyl borate gas chromatographic purity analysis system according to claim 1, characterized in that, It also includes a control feedback module; The control feedback module adjusts the injection volume and injection speed of the autosampler based on the noise reduction requirement characteristics; it sends the injection volume and injection speed adjustment values ​​to the control model of injection volume and injection speed, and sends the total number of steps of the reverse propulsion motor and the piston displacement corresponding to each step of the motor to the forward propulsion motor; it determines the preparation purity of the triethyl borate product based on the resolution factor and the concentration data of electronic grade triethyl borate and each byproduct.

3. The electronic-grade triethyl borate gas chromatographic purity analysis system according to claim 1, characterized in that, The specific process of constructing the control model for injection volume and injection rate is as follows: The inner diameter of the injection needle, injection time, total number of steps of the stepper motor, and piston displacement corresponding to each step of the motor are obtained for the triethyl borate autosampler. The injection volume model and the injection speed model are constructed to describe their mathematical relationship with the injection volume and injection speed. Triethyl borate is driven into the autosampler by a stepper motor and valves. The injection time, the total number of steps of the stepper motor, and the piston displacement corresponding to each step of the motor are set to the initial preset values.

4. The electronic-grade triethyl borate gas chromatographic purity analysis system according to claim 1, characterized in that, The specific process for controlling the injection port temperature during the injection process is as follows: During the injection process, the temperature error between the injection port temperature and the preset injection temperature is acquired in real time; The temperature error is analyzed using a fuzzy PID control algorithm to calculate the temperature control quantity, and the injection port temperature is adjusted based on feedback. The specific process is as follows: At preset time intervals, the rate of change of temperature error is calculated, and fuzzification is performed based on the temperature error and its rate of change; the basic universe of discourse is obtained, including the basic universe of discourse of temperature error and the basic universe of discourse of the rate of change of temperature error, i.e. the data distribution range; The quantization factor and quantization value of temperature error are calculated based on the quantization domain, and the quantization factor and quantization value of temperature change rate error are calculated based on the quantization domain. The proportional gain, derivative gain, and integral gain are matched with the quantized values ​​of temperature error and temperature change rate error; the proportional gain, derivative gain, and integral gain of the PID control are adjusted in real time based on the correction values ​​of proportional gain, derivative gain, and integral gain. Set upper and lower limits for proportional gain, derivative gain and integral gain in real-time adjustment to prevent integral saturation or runaway; The system acquires the proportional gain, derivative gain, and integral gain at the current moment, calculates the real-time PWM duty cycle adjustment value for the injection port temperature, and sends it to the injection port temperature adjustment module to perform temperature adjustment.

5. The electronic-grade triethyl borate gas chromatographic purity analysis system according to claim 1, characterized in that, The specific process of optimizing the gas sample flow rate and performing column separation using the gas sample retention time versus temperature curve is as follows: The carrier gas flow rate of the gas sample is calculated using the van der Munte equation. Calculate the temperature relationship curve, control the retention time of the gas sample in the stationary phase, and perform column separation; calculate the retention time of the gas sample in the stationary phase. Access the chromatographic column with methyl polysiloxane as the stationary phase, obtain the baseline length of the chromatographic peaks in the column corresponding to each component, and calculate the resolution factor between any two adjacent chromatographic peaks and their corresponding components; Access the flame photometric detector to capture the characteristic spectrum generated when free radicals produced by electronic-grade triethyl borate in a hydrogen-rich flame transition from the excited state back to the ground state. Then, convert the intensity of the flame photometric detector into an electrical signal and send it to the data processing and analysis module.

6. The electronic-grade triethyl borate gas chromatographic purity analysis system according to claim 1, characterized in that, The specific process for calculating the characteristic values ​​of noise reduction requirements is as follows: The electrical signal is denoised by wavelet transform, which filters out the high-frequency part and retains the low-frequency part. The energy spectral density of the high-frequency part and the energy spectral density of the low-frequency part are calculated. The characteristic value of the denoising requirement is obtained by calculating the difference between the energy spectral density of the high-frequency part and the energy spectral density of the low-frequency part.

7. The electronic-grade triethyl borate gas chromatographic purity analysis system according to claim 1, characterized in that, The specific process for obtaining the concentration data of electronic-grade triethyl borate and each byproduct is as follows: Access the flame photometric detector to capture the characteristic spectrum of free radicals generated by electronic-grade triethyl borate in a hydrogen-rich flame environment when they transition from the excited state back to the ground state, i.e., light with a wavelength of 545 nm, and convert the intensity of the flame photometric detector into an electrical signal through an electrical signal. The electrical signal is denoised by wavelet transform, filtering out the high-frequency part and retaining the low-frequency part; the energy spectral density of the high-frequency part and the energy spectral density of the low-frequency part are calculated; the characteristic value of the denoising requirement is obtained by calculating the difference between the energy spectral density of the high-frequency part and the energy spectral density of the low-frequency part. In the low-frequency range, the retention time and peak area of ​​each chromatographic peak are obtained; the retention time and peak area of ​​the main peak corresponding to triethyl borate are obtained, and the characteristic values ​​of the main peak area ratio and the main peak retention time ratio are calculated.

8. The electronic-grade triethyl borate gas chromatographic purity analysis system according to claim 2, characterized in that, The specific process of adjusting the injection volume and injection speed of the autosampler based on the noise reduction requirement characteristics is as follows: If the noise reduction requirement value is greater than the preset threshold, it is determined that the gas chromatography purity data of triethyl borate has a lot of noise. The injection volume and injection speed of the autosampler should be reduced. The injection volume and injection speed are adjusted to 50% of the current value and sent to the gas chromatography sampling and injection module. Based on the injection volume model and injection speed model, the reverse injection time, the total number of steps of the stepping motor and the piston displacement corresponding to each step of the motor are calculated.

9. The electronic-grade triethyl borate gas chromatographic purity analysis system according to claim 2, characterized in that, The specific process for determining the purity of the triethyl borate product is as follows: If both the peak area ratio characteristic value and the peak retention time ratio characteristic value are greater than their preset thresholds, and the resolution factor between any two adjacent chromatographic peaks is greater than the preset threshold, then it is determined that electronic-grade triethyl borate and its reaction byproducts (ethanol, boric anhydride, organic solvent), hydrolysis byproducts (boric acid, ethanol, water), and reaction byproducts (organoborate ester polymers, cyclic compounds, or complex derivatives of boric acid) are sufficiently separated, and the concentration ratio of triethyl borate in the gas sample meets the standard. The peak area ratio characteristic value is then output as the detection concentration of triethyl borate. Otherwise, the concentration ratio of triethyl borate in the gas sample is determined to be substandard.

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