Triphenyl phosphate standard substance structure identification method

Abstract

The invention discloses a triphenyl phosphate standard substance structure identification method, and relates to the technical field of fluorine-containing gas emission reduction, and the method comprises the following steps: obtaining a standardized analysis sample through fluorine-containing matrix separation, target substance enrichment and solvation treatment; a multi-dimensional chromatographic system and a heart cutting technology are adopted, and temperature programming optimization is combined to realize separation and purification of a sample; carrying out multi-dimensional structure analysis and confirmation by using gas chromatography-mass spectrometry, infrared spectroscopy and nuclear magnetic resonance technologies; a five-stage progressive identification algorithm is constructed, and systematic identification is realized by combining a confidence evaluation system and a fluorine-containing interference correction technology; establishing a structural integrity verification and purity quantitative evaluation standard, and outputting a standardized identification report; a method applicability database is established through multi-type fluorine-containing environment verification and process condition adaptability testing. The method effectively solves the problem of accurate identification of triphenyl phosphate in a complex fluorine-containing matrix, and realizes effective removal of interference components such as light gas, hydrofluorocarbon, perfluorinated compounds and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluorine-containing gas emission reduction, and particularly relates to a method for identifying the structure of triphenyl phosphate standard. BACKGROUND

[0002] With the increasingly serious global climate change problem, fluorine-containing gases, as important greenhouse gases, are receiving high attention from the international community. Hydrofluorocarbons, perfluorinated compounds and sulfur hexafluoride have extremely high global warming potential, and their greenhouse effects are hundreds to tens of thousands of times that of carbon dioxide. The entry into force of the Kigali Amendment marks the entry of global fluorine-containing gas emission reduction into the legal constraint stage, and requires countries to gradually reduce the production and use of HFCs during 2019-2047. It is expected that the global temperature will be reduced by 0.4℃ by 2050, so the monitoring, separation and emission reduction technology of fluorine-containing gases has become a key technical field for environmental protection and industrial sustainable development.

[0003] Various organic phosphorus compounds are commonly used as flame retardants, plasticizers and reaction catalysts in fluorine-containing gas emission reduction processes. Triphenyl phosphate is widely used in the production of fluorine-containing polymers, the recovery and treatment of fluorine-containing refrigerants and the purification process of fluorine-containing electronic gases due to its excellent flame retardant performance and chemical stability. Triphenyl phosphate not only effectively improves the thermal stability and flame retardant performance of fluorine-containing materials, but also plays a solvation and stabilization role in the separation process of fluorine-containing gases. However, the accurate identification and quantitative analysis of triphenyl phosphate in a fluorine-containing environment face serious challenges. The presence of hydrofluorocarbons and perfluorinated compounds can seriously interfere with conventional chromatography-mass spectrometry analysis, resulting in inaccurate detection results.

[0004] Traditional triphenyl phosphate detection methods mainly rely on gas chromatography-mass spectrometry technology, but in the presence of fluorine-containing compounds in complex matrix, these methods have five core technical problems; First, the separation problem of fluorine-containing matrix, light gases such as methane, hydrogen fluoride compounds HFC-134a and HFC-125, perfluorinated compounds CF4 and C2F6 coexist with triphenyl phosphate in the sample, lack of effective selective separation technology, resulting in serious matrix interference; Second, the target enrichment is difficult, the concentration of triphenyl phosphate in the fluorine-containing environment is often low, and the existing enrichment methods such as traditional solid-phase extraction are insufficient in selectivity and efficiency for benzene-based organophosphorus compounds; Third, the chromatographic separation challenge, the boiling point range of fluorine-containing compounds and triphenyl phosphate overlaps, and single-dimensional chromatographic system is difficult to achieve complete separation, especially under the condition of programmed temperature, co-elution is easy to occur; The fourth problem is the lack of accuracy of structure confirmation, the fluorine-containing fragment ions produced under the condition of electron impact ionization will interfere with the characteristic ions of triphenyl phosphate, only relying on GC-MS cannot realize reliable structure confirmation, which needs multi-technology combination verification; The fifth is the standardization problem of data processing and result determination, lacking special identification algorithm and confidence evaluation system for fluorine-containing interference environment, it is difficult to accurately evaluate the reliability of the detection results.

[0005] In the industrial practice of fluorine-containing gas emission reduction, accurate qualitative analysis of triphenyl phosphate is urgently needed; On the one hand, triphenyl phosphate is an important process aid, and its content and purity directly affect the efficiency of fluorine-containing gas treatment process and product quality; On the other hand, triphenyl phosphate is also an important environmental pollutant, which needs to be strictly monitored for its residual in waste gas and waste water. However, the existing detection methods have significant shortcomings in the applicability, detection accuracy and reliability of the results in the presence of fluorine-containing environment, which are difficult to meet the technical requirements of fluorine-containing gas emission reduction process and the standard requirements of environmental supervision.

[0006] In view of the above problems, the present application provides a standard structure identification method for triphenyl phosphate, which realizes effective separation of fluorine-containing matrix through low-temperature cold trap and multi-layer composite adsorbent system, uses SPME technology for selective enrichment of target, constructs heart cutting technology double column multi-dimensional chromatographic system for accurate separation, combines GC-MS, FTIR and NMR technologies for comprehensive structure confirmation, establishes five-level progressive identification algorithm and confidence evaluation system, and verifies the wide applicability of the method through multi-parameter process adaptability test, effectively solves the technical problems of triphenyl phosphate detection in the presence of fluorine-containing compounds, and provides reliable technical support for accurate analysis and process control of organic phosphorus compounds in fluorine-containing gas emission reduction process. SUMMARY

[0007] The present application is directed to the above problems, and provides a phosphorus acid triphenyl standard structure identification method to solve the problem that the prior art cannot accurately separate, detect and identify phosphorus acid triphenyl in a complex fluorine-containing environment, resulting in unreliable detection results.

[0008] To solve the above technical problems, the present application provides the following technical scheme: a phosphorus acid triphenyl standard structure identification method, comprising the following steps: Step S1, through fluorine-containing matrix separation, target enrichment and solvation treatment, effective separation and pre-concentration of phosphorus acid triphenyl in the sample are realized, fluorine-containing interfering components are removed, target compounds are enriched, and a standardized analysis sample is obtained; In step S1, the following sub-steps are further included: S1-1, fluorine-containing matrix separation, the original sample is pretreated by low-temperature cold trap technology, selective separation is realized through a multi-layer composite adsorbent system, and liquid-liquid extraction technology is used to separate perfluorinated compounds to obtain a pretreated sample; S1-2, target enrichment, phosphorus acid triphenyl in the pretreated sample is enriched and concentrated by using solid-phase microextraction technology, PDMS / DVB composite coating fiber is selected as the extraction medium, and an enriched sample is obtained by thermal desorption operation; S1-3, sample standardization treatment, the enriched sample is subjected to solvation treatment, acetonitrile is used as the dissolving medium, and internal standard substance diphenyl phenyl phosphate is added for quantitative correction, and a standardized analysis sample is obtained.

[0009] Step S2, through multi-dimensional chromatography system construction, program temperature optimization and carrier gas injection condition setting, high-efficiency separation of the standardized analysis sample is realized by using heart-cutting technology and a double-column system, and high-purity phosphorus acid triphenyl is obtained; In step S2, the following sub-steps are further included: S2-1, multi-dimensional chromatography system separation, a multi-dimensional chromatography separation system is constructed, RT-Q-BOND open-pore coating column and DB-5MS silica gel capillary column are connected by heart-cutting technology, the standardized analysis sample is preliminarily separated, and preliminary separation components are obtained; S2-2, program temperature fine separation, the program temperature conditions are optimized to realize the stage separation of different components, the system is preheated to-20℃ and is heated to 300℃ according to the set gradient, the preliminary separation components are finely treated, and separation and purification components are obtained; S2-3, carrier gas optimization and component collection, high-purity helium is used as the carrier gas, program temperature vaporization technology and split / non-split composite strategy are used to accurately collect in the phosphorus acid triphenyl retention time window, and high-purity phosphorus acid triphenyl is obtained.

[0010] Step S3, high-purity triphenyl phosphate is subjected to structural analysis and confirmation by gas chromatography-mass spectrometry, infrared spectroscopy and nuclear magnetic resonance technology. The molecular structure and purity of the triphenyl phosphate are verified through multi-dimensional spectral information to obtain a structure fully confirmed component; In step S3, the following sub-steps are further included: S3-1, gas chromatography-mass spectrometry structural analysis, GC-MS system is used to analyze the structure of high-purity triphenyl phosphate. The characteristic ions are detected by full scan mode and selected ion monitoring mode to confirm the molecular ion peak and characteristic fragment ions, and the mass spectrometry confirmed component is obtained; S3-2, infrared spectroscopy structural confirmation, the mass spectrometry confirmed component is subjected to structural confirmation by attenuated total reflection Fourier transform infrared spectroscopy. The P=O stretching vibration peak, benzene ring skeleton vibration peak and P-O-C stretching vibration peak characteristic absorption are identified, and the infrared confirmed component is obtained; S3-3, precise structure identification by nuclear magnetic resonance, the infrared confirmed component is subjected to precise structure identification by nuclear magnetic resonance technology. The molecular structure and chemical environment are confirmed by 31 P NMR, 1 H NMR and 13 C NMR test, and the structure fully confirmed component is obtained.

[0011] Step S4, the GC-MS, FTIR and NMR analysis data of the structure fully confirmed component are subjected to systematic identification by five-level progressive identification algorithm, confidence evaluation system and fluorine-containing interference correction technology, and an identification result report is obtained; In step S4, the following sub-steps are further included: S4-1, five-level progressive identification algorithm construction, a five-level progressive identification algorithm system is constructed. The structure fully confirmed component is verified step by step in the order of GC-MS-IR-NMR. The preliminary identification result is obtained by retention time screening, molecular ion peak confirmation, fragment pattern matching, IR characteristic peak verification and NMR chemical shift confirmation; S4-2, confidence evaluation and interference correction, an identification confidence evaluation system is established. The identification result report is obtained by comprehensive evaluation according to the number and quality of identification levels, fluorine-containing interference evaluation and correction algorithm.

[0012] Step S5, the identification result report is subjected to comprehensive judgment by structure integrity verification, purity quantitative evaluation and standardized report generation. The triphenyl phosphate confirmation standard and purity grading system are established, and the standardized identification report is finally output; In step S5, the following sub-steps are further included: S5-1, structural integrity determination criteria, establish structural integrity determination criteria, cross-verify target molecular structure by multi-dimensional spectral data, establish structural integrity scoring system by molecular ion peak verification, functional group integrity test and nuclear magnetic resonance verification, and obtain structural confirmation results; S5-2, purity quantitative evaluation criteria, develop purity quantitative evaluation criteria, jointly quantitatively analyze by chromatographic purity determination, mass spectrometric purity calculation and nuclear magnetic purity determination, establish purity grading criteria, and obtain purity evaluation results; S5-3, standardized identification report output, design a standardized identification report output system, establish a unified report format and determination criteria, including qualitative conclusion, confidence level, interference evaluation and recommended measures, and output a standardized identification report.

[0013] Step S6, by verifying multiple types of fluorine-containing environments, process condition adaptability test and environmental tolerance evaluation, the applicability of the established identification method of triphenyl phosphate in S1-S5 under different fluorine-containing environments and process conditions is systematically evaluated, a method applicability database and application guidance principle are established, and a process applicability evaluation report is obtained.

[0014] In step S6, the following sub-steps are further included: S6-1, multi-fluorine-containing environment applicability verification, construct multiple fluorine-containing environment simulation systems, systematically evaluate the detection performance of the method under the interference of different fluorine-containing compounds such as HFCs, PFCs, SF6 and methane, and form an environmental applicability database; S6-2, process condition adaptability evaluation, establish a multi-parameter process condition test platform, comprehensively evaluate the stability and reliability of the method under different temperature, pressure and humidity conditions, and form a process adaptability data; S6-3, comprehensive applicability evaluation and application guidance, establish an environmental factor comprehensive influence evaluation model, develop operation guidance principles for different application scenarios, conduct extreme condition tolerance tests, and generate a process applicability evaluation report.

[0015] Compared with the prior art, the beneficial effects of the present application are: The present application realizes efficient removal of multiple types of fluorine-containing interference components such as hydrofluorocarbons, perfluorinated compounds and sulfur hexafluoride by low-temperature cold trap technology combined with a three-layer composite adsorbent system, effectively solving the technical problem that traditional methods cannot effectively separate target substances in fluorine-containing environments; solid-phase microextraction technology is used in combination with PDMS / DVB composite coating fibers to significantly improve the enrichment efficiency of triphenyl phosphate under optimized conditions, realizing high-sensitivity detection of trace samples.

[0016] The multi-dimensional chromatographic separation system constructed by the application adopts heart-cutting technology to connect RT-Q-BOND and DB-5MS double-column systems, realizes complete baseline separation of triphenyl phosphate and fluorine-containing interfering components through program temperature optimization and precise switching time control, and greatly improves the reliability and accuracy of identification results through the established GC-MS, ATR-FTIR and NMR three-technology combined identification system and five-level progressive identification algorithm system.

[0017] The fluorine-containing interference correction algorithm developed by the application can automatically identify and correct different degrees of interference of fluorine-containing compounds, and can maintain stable high detection success rate under conditions of light interference, moderate interference and severe interference; the applicability evaluation system established comprehensively covers multiple parameter process conditions such as temperature, pressure and humidity, and has stable and reliable detection performance in four different application scenarios, greatly expanding the application range of the method.

[0018] The green analysis technology concept is adopted, the use amount of organic solvent is greatly reduced through SPME technology, the total detection time of the optimized analysis process is significantly shortened to less than 45 minutes, the analysis efficiency is improved, and the environmental burden and analysis cost are significantly reduced; the standardized identification report system realizes the intelligent output of the whole process from the qualitative conclusion, the confidence level, the interference evaluation to the technical suggestion, establishes a unified judgment criterion and a standardized report format, and completely eliminates the subjectivity and randomness of manual judgment in the traditional method. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments, and the following drawings only show some embodiments of the application, and should not be regarded as limiting the scope, and for those skilled in the art, other related drawings can be obtained without creative labor.

[0020] Figure 1 It is a method flowchart of the application. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the embodiments of the application more clear, the technical scheme in the embodiments of the application will be clearly and completely described in the following combined with the drawings in the embodiments of the application. Obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the application. Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the claimed application, but only for selected embodiments of the application.

[0022] Referring to Figure 1 , Figure 1 is a phosphorus triphenyl standard structure identification method flow chart provided by the embodiment of the application, comprising the following steps: Step S1, through fluorine-containing matrix separation, target enrichment and solvation treatment, effective separation and pre-concentration of phosphorus triphenyl in the sample are realized, fluorine-containing interfering components in the sample are effectively removed, target compounds are enriched, and finally purified standardized analysis samples are obtained.

[0023] S1-1, to realize effective separation of the fluorine-containing matrix, first, the original sample is pretreated by using a low-temperature cold trap technology (-10±2℃), light gases (methane) in the sample are selectively condensed and separated under low-temperature conditions by using a semiconductor refrigerator, the precooling time is set to 15-30 min, and the carrier gas flow rate is controlled to be 50-100 mL / min; Further, a multi-layer composite adsorbent system is used to realize selective separation, and a three-layer adsorption system is constructed; among them, the first layer of activated alumina (100-200 mesh, adsorption capacity > 50 mg / g) is used to remove hydrofluorocarbon compounds (HFCs) in the sample, the second layer of modified silica gel is specially used to capture specific components such as HFC-134a and HFC-125, and the third layer of Tenax-TA is responsible for removing volatile organic matter interference, the whole adsorption process is carried out at 5-15℃, the sample flow rate is maintained at 20-50 mL / min, and then thermal desorption is completed at 200-250℃. For perfluorocarbons (CF4, C2F6) in the sample, liquid-liquid extraction technology is used for separation: deionized water is prepared as the aqueous phase (pH 6.5-7.5), n-hexane-toluene (3:1, v / v) is used as the organic phase, the volume ratio of the two phases is 2:1, 300W ultrasonic extraction is carried out at room temperature for 15 min, and the sample is allowed to stand for 10 min; the organic phase is taken as the final pretreated sample.

[0024] S1-2, the phosphorus triphenyl in the pretreated sample is enriched and concentrated by using a solid phase microextraction (SPME) technology, and a PDMS / DVB (polydimethylsiloxane / diphenylstyrene copolymer) composite coating fiber is selected as the extraction medium; the extraction conditions are set to be constant temperature at 40℃, the SPME fiber is placed in the sample for adsorption for 30 min, the magnetic stirring speed is 500 rpm, 5% (w / v) NaCl is added for salting-out to improve the enrichment efficiency; In the desorption operation, the SPME fiber saturated with adsorption is directly inserted into the gas chromatography inlet, and is thermally desorbed at 250℃ for 5 min, the carrier gas (helium) flow rate is 2.0 mL / min, the phosphorus triphenyl enriched on the fiber is completely desorbed and enters the collection device, and the enriched sample is obtained through this step.

[0025] S1-3, the enriched sample is solvated by using acetonitrile as the dissolving medium to completely dissolve the enriched triphenyl phosphate. The sample is prepared into a series of concentrations of 100-1000 μg / mL according to the analytical requirements. The concentration range required for the standard curve is obtained by stepwise dilution. Diphenyl phenyl phosphate (DPP) was added as an internal standard for quantitative correction. The ratio of internal standard to sample mass was 1:1. This was used to correct systematic errors in the sample preparation and analysis process. Standardized analytical samples were obtained through the above treatment.

[0026] Through the above processing steps, fluorine-containing interfering components such as light gases, hydrofluorocarbons, and perfluorinated carbon are effectively removed from the sample, achieving selective enrichment and standardized preparation of triphenyl phosphate, and obtaining a clean sample suitable for multidimensional chromatographic separation and analysis.

[0027] In step S2, through the construction of a multidimensional chromatography system, optimization of temperature program and setting of carrier gas injection conditions, the standardized analytical sample is efficiently separated using core cutting technology and a dual-column system to achieve precise separation of triphenyl phosphate from residual interfering components, and finally obtain the target component with high purity.

[0028] S2-1 describes a multidimensional chromatographic separation system that uses a core-cutting technique to connect two columns of different polarities. The first-dimensional column is an RT-Q-BOND open-tube porous coated column with a head pressure set at 120 kPa, used for the preliminary separation of residual light gases (methane), hydrofluorocarbons (HFCs), and perfluorinated carbons (CF4, C2F6) in standardized analytical samples. The second-dimensional column is a DB-5MS silica capillary column with a head pressure set at 80 kPa, specifically for the separation of triphenyl phosphate. A core-cutting valve, equipped with a six-way valve and a quantitative loop, is located between the two columns and automatically switches within the triphenyl phosphate retention time window with a switching time accuracy of ±0.1 min, quantitatively transferring the target component to the two-dimensional column for fine separation. The system is equipped with a pressure sensor to monitor pressure changes at each stage, ensuring stable column flow and ultimately obtaining the preliminarily separated components, achieving effective separation of triphenyl phosphate from the main interfering components.

[0029] S2-2, Optimize the programmed temperature rise conditions to achieve staged separation of different components, and perform fine processing on the initially separated components: Preheat the system to the initial temperature of -20℃ and stabilize for 10 min, then start the programmed temperature rise: Hold the initial temperature of -20℃ for 3 min to completely separate residual light gases; Rise to 80℃ at 5℃ / min, and monitor the elution of hydrofluorocarbons (HFC-134a, HFC-125, etc.) in the range of 60-70℃ during this stage; Rise to 150℃ at 3℃ / min to separate residual perfluorinated carbons (CF4, C2F6, etc.), and set the flow rate automatic compensation to constant linear velocity mode during this stage; Rise to 200℃ at 2℃ / min to elute heavy fluorides, and the detector signal intensity should be maintained within ±5% of the baseline at this time; Finally, Rise to 300℃ at 10℃ / min and hold for 10 min to ensure complete elution of triphenyl phosphate, obtain the separated and purified components, and allow to cool naturally to 50℃ after the temperature rise is completed in preparation for the next sample injection.

[0030] S2-3 uses high-purity helium as the carrier gas, which is precisely regulated by a mass flow controller. The carrier gas linear velocity is 35 cm / s, corresponding to a column head pressure of 120 ± 2 kPa. The carrier gas is purified by a molecular sieve dryer and an oxygen trap. The inlet is equipped with a pressure regulating valve and a flow indicator for real-time monitoring. The injection port uses programmed temperature vaporization technology, equipped with a quartz glass liner and filled with a quartz glass wool injection pad. The initial temperature is 50℃ and held for 0.1 min, then increased to 280℃ at 300℃ / min and held for 5 min. The injection port diaphragm is replaced every 20 injections. The purified fraction was separated and injected using an autosampler at a rate of 1 μL / s. The needle cleaning program was set to acetonitrile-n-hexane (1:1) for three washes. A split / splitless hybrid strategy was employed, with an initial 0.5 min of splitless injection to improve sensitivity and a diaphragm purge flow rate of 30 mL / min. Subsequently, a split flow (10:1 split ratio) was initiated to protect the column at a flow rate of 12 mL / min. The column oven was equipped with a forced air cooling system with a cooling rate >10℃ / min. Precise collection was performed within the retention time window of triphenyl phosphate (approximately 18-20 min), and the eluted high-purity triphenyl phosphate was collected into a pre-cooled collection bottle using an automated fraction collector.

[0031] In addition, a system leak test is performed before daily sample injection, and column efficiency is tested using n-hexadecane standard with a theoretical plate number >3000 / m; baseline noise is measured regularly, and the signal-to-noise ratio should be >100:1; solvent blank and standard are injected before and after each batch of sample analysis to confirm system stability; The purity of the collected high-purity triphenyl phosphate was verified: qualitative confirmation was performed by GC-MS, with a mass spectrometry matching degree >90%; quantitative purity was performed by high performance liquid chromatography (HPLC), with the main peak area ratio >98%; and structural confirmation was performed by nuclear magnetic resonance (NMR).

[0032] By using a multidimensional chromatographic separation system, complete separation of triphenyl phosphate from residual interfering components in standardized analytical samples is achieved, ultimately yielding high-purity triphenyl phosphate.

[0033] Step S3 involves using gas chromatography-mass spectrometry, infrared spectroscopy, and nuclear magnetic resonance to analyze and confirm the structure of high-purity triphenyl phosphate. By verifying the molecular structure and purity of triphenyl phosphate through multi-dimensional spectral information, the pure target component with confirmed structure is finally obtained.

[0034] S3-1. The structure of high-purity triphenyl phosphate was determined using a gas chromatography-mass spectrometry (GC-MS) system. The mass spectrometer was equipped with a quadrupole mass analyzer, a scan rate of 2.5 scans / s, and an electron multiplier voltage of 1500V. The ionization source used in the mass spectrometry was an electron impact ionization (EI) source with an electron energy of 70 eV, an emission current of 200 μA, and an ion source vacuum degree of <5 × 10⁻⁻⁻⁶. 5 Pa; ion source temperature 250℃, transfer line temperature 290℃, quadrupole temperature 150℃; the injection system adopts split injection with a split ratio of 10:1, injection port temperature 280℃, and carrier gas helium flow rate 1.2mL / min; Data acquisition employed a full-scan mode combined with selected ion monitoring (SIM) to detect characteristic ions. The molecular ion peak of triphenyl phosphate was located at m / z 326, with a base peak at m / z 251. Important fragment ions included m / z 215, m / z 169, m / z 141, and m / z 77. A database of characteristic ion intensity ratios was established: R1 = I 251 / I 326 =3.8±0.3, R2=I 215 / I 251 =0.45±0.05, R3=I 77 / I 251 =0.25±0.03; The NIST14 standard spectral library was used for mass spectrometry library search, and a fluorine-containing fragment ion filtering algorithm was established to automatically exclude interfering ions such as m / z 69 (CF3⁺), 119 (C2F5⁺), and 169 (C3F7⁺); Instrument tuning was performed daily, and the mass axis was calibrated using perfluorotributylamine (PFTBA) with a mass accuracy of ±0.1 amu; Molecular ion peaks and characteristic fragment ions were identified through mass spectrometry fragment mode analysis to obtain mass spectrometry-confirmed components and verify the molecular weight and basic structural information of the target compound.

[0035] S3-2, Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) was used to confirm the structure of the mass spectrometry-confirmed components. The instrument was equipped with an MCT detector, a signal-to-noise ratio >10000:1, and a spectral resolution of 4 cm⁻¹. 1The number of scans is 32 times cumulatively; the ATR accessory uses diamond crystal, with an incident angle of 45° and an effective penetration depth of 1-2μm; the sample preparation adopts micro-sampling technology, with a sample volume of 2-5mg, which is directly attached to the surface of the ATR prism and a pressure of 5-10N is applied to ensure good contact. Scanning range 4000-400cm⁻ 1 The scanning speed was 0.6329 cm / s, and the spectral data point density was 0.482 cm⁻. 1 Spectral preprocessing includes baseline correction, smoothing, and normalization; identification of characteristic absorption peaks of triphenyl phosphate: P=O stretching vibration peak at 1200±2 cm⁻ 1 The vibrational peaks of the benzene ring skeleton were 1595±3, 1495±3, and 1445±3 cm⁻ 1 POC stretching vibration peaks: 1188±5, 1163±5, 1024±5 cm⁻ 1 Establish characteristic peak intensity ratio: I 1200 / I 1595 =1.2±0.1, I 1188 / I 1163 =0.8±0.1; Monitoring 1000-1350cm⁻ 1 The CF vibration peaks within the range were automatically excluded by software algorithms to eliminate interference from fluorinated compounds; 64 background scans were performed with air before each measurement, and the ATR crystal surface was cleaned with ethanol after each batch of samples was measured; the spectral library comparison was performed using the Wiley and NIST infrared libraries, with a similarity >0.95; the functional group characteristics and molecular bonding information of triphenyl phosphate were confirmed by infrared characteristic absorption peak analysis, and the infrared-confirmed component verified by infrared spectroscopy was obtained.

[0036] S3-3 employs nuclear magnetic resonance (NMR) technology for precise structural identification of infrared-confirmed components. The operating frequency of the NMR spectrometer... 1 H 400MHz, 13 C 100MHz, 31 P 162MHz, magnetic field strength 9.4T, sample tube 5mm standard NMR tube; sample preparation used deuterated chloroform as solvent, sample concentration 10-50mg / mL, sample volume 600μL; 31 P NMR testing conditions: pulse width 30° (6 μs), relaxation delay 2 s, acquisition time 1.5 s, spectral width 25000 Hz, data points 64 K, accumulation count 256, using 85% phosphoric acid as an external standard (δ=0 ppm), triphenyl phosphate. 31 P chemical shift δ = -17.8 ± 0.1 ppm, signal linewidth < 2 Hz, signal-to-noise ratio > 100:1; 1H NMR test conditions: pulse width 30° (8μs), relaxation delay time 1s, acquisition time 3s, spectrum width 8000Hz, data points 32K, accumulation number 64, detection of benzene ring aromatic proton signal 7.05-7.36ppm (multiple peaks, integration 15H), coupling constant J=7-8Hz; 13 C NMR testing conditions: pulse width 30° (12μs), relaxation delay time 2s, acquisition time 1s, spectrum width 25000Hz, data points 64K, proton decoupling, 1024 accumulations, confirming the molecular carbon skeleton, quaternary carbon signal 151.9±0.2ppm, tertiary carbon signals 129.7±0.2, 125.7±0.2, 120.2±0.2ppm, and the chemical shift deviation from the theoretical value is <0.5ppm; Data processing was performed using Mestrenova software, including phase correction, baseline correction, and chemical shift calibration. Chemical shift was calibrated daily using TMS standards, with temperature controlled at 25±1℃ and magnetic field shimming adjusted to a full width at half maximum (FWHM) <1Hz. Three-dimensional NMR information was then analyzed. 1 H, 13 C 31 P NMR fully confirmed the molecular structure and chemical environment of triphenyl phosphate, obtaining a fully confirmed component.

[0037] S3-4, Conduct comprehensive data analysis on the structurally confirmed components and establish a multi-technology confirmation database: GC-MS mass spectrometry matching degree >90%, characteristic ion ratios conform to the standard range; ATR-FTIR spectral similarity >0.95, characteristic peak intensity ratios within the allowable deviation range; NMR chemical shift deviation from theoretical value <0.5ppm, integral ratio consistent with molecular structure; Purity was confirmed by the following indicators: the main peak area ratio in the GC-MS chromatogram was >98%, and the relative intensity of impurity peaks was <2%; there were no abnormal impurity peaks in the infrared spectrum, and the baseline was stable; there were no impurity signals in the NMR spectrum, and the integral value matched the theoretical value; a comprehensive purity evaluation index PI was established as 0.4×PGC-MS+0.3×PFTIR+0.3×PNMR, and a PI>0.98 was considered a high-purity sample; finally, a fully confirmed component with a structure verified by multiple technologies was obtained.

[0038] By combining multiple techniques such as GC-MS, ATR-FTIR, and multidimensional NMR, complete structural confirmation data of triphenyl phosphate were obtained, including mass spectrometry fragmentation modes, infrared characteristic absorption, and nuclear magnetic resonance chemical shift information. This enabled comprehensive structural verification and purity confirmation of the target compound, ultimately yielding a fully confirmed structural component that can be used for quantitative analysis.

[0039] Step S4 involves systematically identifying the GC-MS, FTIR, and NMR analysis data of the structurally confirmed components obtained in step S3 using a five-level progressive identification algorithm, a confidence assessment system, and fluorine-containing interference correction technology. This process achieves accurate identification and confidence evaluation of triphenyl phosphate, ultimately yielding an identification result report.

[0040] S4-1, a five-level progressive identification algorithm system was constructed to verify the target analyte signal step by step according to the GC-MS-IR-NMR sequence: Level 1 identification used GC retention time window screening, setting the reference range for the retention time of triphenyl phosphate based on the chromatographic conditions established in step S2, with a window width of ±0.5 min and a temperature compensation coefficient of 0.02 min / ℃; Level 2 identification used MS molecular ion peak confirmation, detecting the molecular ion peak (M⁺·) in the m / z range of 325.5-326.5, based on the molecular formula C 18 H 15 The theoretical molecular weight of O4P is 326, with a mass accuracy of ±0.1 amu. Level 3 identification uses MS fragment mode matching to verify characteristic ions: molecular ion peak m / z 326, base peak m / z 251 [M-C6H5O]⁺, fragment ions m / z 215, 169, 141, 77 [C6H5]⁺, NIST library matching ≥90%, and automatic filtering of fluorine-containing fragment ions. Level 4 identification verifies characteristic IR peaks, detecting the P=O stretching vibration peak (approximately 1200 cm⁻). 1 ), benzene ring skeletal vibration peak (approximately 1595 cm⁻) 1 POC stretching vibration peak (1100-1200cm⁻) 1 Peak position offset tolerance ≤10cm⁻ 1 Level 5 identification uses NMR chemical shift confirmation. 31 The expected P-nucleus signal is δ = -17 to -18 ppm. 1 H aromatic protons 7.0-7.4 ppm (integrated over 15H). 13 The C-level carbon signal is approximately 150-155 ppm, with a deviation tolerance of ≤0.2 ppm and a signal-to-noise ratio of ≥50:1. Through five-level progressive verification, the pass status and confidence score of each level of identification are obtained, forming a preliminary identification result.

[0041] S4-2, Establish a confidence assessment system for identification. The preliminary identification results are comprehensively evaluated based on the quantity and quality of the identification levels passed. Confidence level grading standards are as follows: High confidence: passing all five levels of identification; Medium confidence: passing the first four levels of identification, with acceptable bias in the NMR data; Low confidence: passing the first three levels of GC-MS identification; Uncertain: failing any of the first three levels. Confidence calculation model: in, The weights are for the i-th level (W1=0.1, W2=0.2, W3=0.3, W4=0.2, W5=0.2). This represents the i-th level pass state (1 or 0). The quality coefficient for level i is 0.5-1.0 (based on the degree of bias); a confidence assessment report is automatically generated, providing a confidence assessment result that includes the confidence level, rating details, and quality assessment.

[0042] S4-3 employs a fluorine-containing interference assessment and correction algorithm to analyze the interference impact and correct parameters in the confidence assessment results. Interference levels are categorized as: mild interference (fluorine compound signal intensity < 10 times baseline noise), moderate interference (10-100 times), and severe interference (> 100 times). The interference level is assessed by monitoring the characteristic ion peak intensity of fluorine compounds using GC-MS. Parameter correction strategies include: increasing the MS detection sensitivity threshold by 30% for moderate interference, adjusting the SIM mode residence time, and appropriately extending the SPME extraction time; increasing the detection sensitivity threshold by 50% for severe interference, optimizing the carrier gas flow rate and injection port temperature, and re-processing S1-S2 if necessary. An interference correction database is established to record optimization schemes for identification parameters under different interference levels. Quality control measures include daily standard verification, establishing traceable records of identification results, regular algorithm performance evaluation, automatic retesting for samples with a confidence level < 85%, and establishing standard operating procedures (SOPs) and personnel training mechanisms. Finally, an identification result report containing complete identification information, confidence assessment, and quality control data is generated.

[0043] By employing an intelligent five-level progressive identification algorithm, combined with confidence assessment and interference correction techniques, a systematic identification and reliability evaluation of triphenyl phosphate is achieved, ultimately yielding an identification report that meets analytical quality requirements.

[0044] Step S5 involves comprehensively evaluating the identification results obtained in step S4 through structural integrity verification, quantitative purity assessment, and standardized report generation. This process establishes a confirmation standard and purity grading system for triphenyl phosphate, ultimately outputting a standardized identification report.

[0045] S5-1, Establish structural integrity criteria and use multidimensional spectral data cross-validation to comprehensively evaluate the molecular structure of the target analyte in the final identification report. Molecular ion peak validation requires a relative abundance of ≥15% for the m / z 326 peak in the GC-MS spectrum, peak symmetry of 0.8-1.2, half-maximum width at half maximum (FWHM) ≤0.5 amu, and baseline resolution ≥1.5. Functional group integrity verification requires the presence of the P=O stretching vibration peak (approximately 1200 cm⁻¹) in the IR spectrum. 1 Intensity ≥ 0.8 (relative intensity), benzene ring skeletal vibration peaks (approximately 1595, 1495, 1445 cm⁻) 1The entire region (referring to a specific region) appeared, with the POC stretching vibration peak (1100-1200 cm⁻). 1 The intensity ratio of the region meets the reference range for standard samples; nuclear magnetic resonance verification requirements. 1 The HNMR aromatic proton signal is 7.0-7.4 ppm with an integral value of approximately 15 Hz, and the coupling constant is 7-8 Hz. 31 The expected PNMR signal is in the region of -17 to -18 ppm with a linewidth < 2 Hz. 13 CNMR signal for quaternary carbon is approximately 150-155 ppm, and for tertiary carbon it is approximately 120-130 ppm; stereostructure confirmation passed. 13 C peak position deviation ≤0.5ppm and 1 H-coupling mode verifies molecular symmetry; establish a structural integrity scoring system: full score 100 points, molecular ion peak accounts for 30 points, functional group integrity accounts for 40 points, stereostructure accounts for 30 points, and a total score ≥85 points is used to determine structural integrity; finally obtain the structural integrity score and verification status of the structural confirmation results.

[0046] S5-2, Establish purity quantitative assessment standards, and use multi-technology combined quantitative analysis to determine the purity level of the target analyte in the structural confirmation results. Chromatographic purity determination uses the GC-TIC peak area normalization method, with the triphenyl phosphate main peak area accounting for ≥99.0%, the total impurity peak area ≤1.0%, single peak purity within the retention time window, and peak tailing factor ≤2.0. Mass spectrometry purity calculation uses the peak purity index algorithm: PI = Itarget peak / (Itarget peak + Iimpurity peak), requiring PI ≥0.95, the purity of the target ion signal after background subtraction, and the isotope peak intensity ratio M+1 / M conforming to the theoretical value of 0.196±0.010. NMR purity determination passes... 31 PNMR quantitative analysis was performed, with the target peak integral accounting for ≥98.5% of the total phosphorus signal, impurity phosphorus compound signal ≤1.5%, baseline flatness ±2%, and phase correction error <5°. Purity grading standards were established: premium purity (≥99.5%), superior purity (99.0-99.4%), acceptable purity (98.0-98.9%), and unacceptable purity (<98.0%), with each grade corresponding to different application requirements. Quantitative purity data and purity assessment results of the grading evaluation were obtained.

[0047] S5-3, Design a standardized identification report output system, establish a unified report format and judgment criteria, and standardize the processing of purity assessment results. The report title includes sample number, testing date, operator information, and review status; the qualitative conclusion section clearly indicates "confirmed as triphenyl phosphate," "structurally abnormal," or "cannot be determined," and includes a structural diagram and IUPAC nomenclature; confidence levels are expressed numerically: high confidence 95.1-100%, medium confidence 85.1-95.0%, low confidence 70.1-85.0%, and uncertain ≤70.0%, displaying specific values ​​to one decimal place; the interference assessment section details the type of fluorinated compound (HFCs, PFCs, etc.), the level of interference (mild, moderate, severe), and the corrective measures taken; the recommended measures module automatically generates based on the identification results: confidence level. <95% purity triggers "suggest supplementary NMR analysis", <99% purity prompts "suggest re-purification", and moderate interference suggests "optimize pretreatment conditions"; the technical appendix includes the original spectrum, integral data, parameter settings, and quality control results; the report review process includes a three-tier system of data verification, technical review, and quality approval; quality control measures include verification of standard reference materials for each batch, establishment of an identification results database, standardization of report templates, technical dispute arbitration mechanism, customer feedback system, and periodic proficiency testing comparisons; all identification reports are electronically archived for 10 years and support historical data retrieval; the output is a complete standardized identification report containing qualitative conclusions, quantitative data, confidence level evaluation, and technical recommendations.

[0048] By establishing a criterion system that includes structural integrity verification, quantitative purity assessment, and standardized report generation, we can accurately confirm and classify the purity of triphenyl phosphate, ultimately outputting an identification report that conforms to standard specifications, thus ensuring the scientific validity and traceability of the analytical results.

[0049] Step S6 involves systematically evaluating the applicability of the triphenyl phosphate identification method established in S1-S5 under different fluorine-containing environments and process conditions through multi-type fluorine-containing environment verification, process condition adaptability testing, and environmental tolerance evaluation. A method applicability database and application guidelines are established, and finally, a process applicability evaluation report is obtained.

[0050] S6-1, Constructing multiple fluorine-containing environmental simulation systems, and systematically evaluating the detection performance of a complete method validated based on standardized identification reports under interference from different fluorine-containing compounds. Environmental suitability testing for hydrofluorocarbons (HFCs) employed a ternary mixed interference system of HFC-134a (1,1,1,2-tetrafluoroethane), HFC-125 (pentafluoroethane), and HFC-32 (difluoromethane), with interference concentration gradients set at 10-500 ppm. Validation was conducted at room temperature (25±2℃) and relative humidity (45±5%). Triphenyl phosphate sample concentrations ranged from 100-1000 μg / mL, with each concentration level measured six times. The detection success rate was statistically determined using the confidence level. With a purity ≥95% and a structural integrity score ≥85, the detection success rate is >98.5% when the total HFC concentration is ≤200ppm, and >97.2% under high interference conditions of 300-500ppm. Interference mechanism analysis shows that the low-temperature pre-separation (-10±2℃) and multilayer composite adsorbent system in step S1 can effectively remove HFC interference. The theoretical adsorption capacity of activated alumina is >50mg / g, and the selective adsorption efficiency of modified silica gel for HFC-134a is >95%. The environmental suitability verification of perfluorinated compounds (PFCs) adopted a multi-component interference system of CF4 (tetrafluoromethane), C2F6 (hexafluoroethane), and C3F8 (octafluoropropane), with interference concentrations set at 20-800 ppm. The test conditions were atmospheric pressure and a temperature range of 20-40℃. The detection success rate of triphenyl phosphate was >96.8% when the PFC concentration was ≤300 ppm, and >94.5% under extremely high interference of 500-800 ppm. The liquid-liquid extraction separation effect evaluation of step S1 showed that the theoretical partition coefficient of hexane-toluene (3:1, v / v) organic phase relative to PFCs was <0.02. Ultrasonic extraction at 300W for 15 min was expected to achieve a PFC removal rate of >98%. The optimal pH value of the aqueous phase was controlled in the range of 6.5-7.5, and the highest extraction efficiency was achieved when the two-phase volume ratio was 2:1. The SF6 environmental tolerance test was conducted with an SF6 concentration range of 50-500 ppm. Detection performance was evaluated under standard laboratory conditions. It was expected that the success rate of triphenyl phosphate identification would remain >99.2% at an SF6 concentration of 200 ppm, and the target success rate would be >97.8% under the extreme condition of 500 ppm. As a relatively inert gas, SF6 mainly causes interference through physical adsorption. The Tenax-TA adsorbent in step S1 has a theoretical adsorption capacity of approximately 18 mg / g for SF6 at 5-15℃, and thermal desorption at 200-250℃ is expected to achieve a desorption rate of >99.5%. The methane coexistence environment validation test investigated the effect of methane concentrations of 100-2000 ppm on detection. When the methane concentration was ≤1000 ppm, it was expected to have no significant interference with the identification of triphenyl phosphate, with a target detection success rate >99.8%. The low-temperature cold trap technology (-10±2℃) in step S1 can effectively separate methane. After a pre-cooling time of 15-30 min, the methane removal rate is expected to be >99.9%. In the GC separation of step S2, the methane retention time is about 1.8 min, and it is completely separated from the target window of triphenyl phosphate. Ultimately, method performance data and applicability assessments are obtained under different fluorine-containing environments, forming an environmental suitability database.

[0051] S6-2, Establish a multi-parameter process condition testing platform to comprehensively evaluate the stability and reliability of the method under different operating environments, and conduct in-depth analysis based on environmental suitability data. Temperature adaptability testing covered a range of -20℃ to 200℃, with test points set at -20℃, 0℃, 25℃, 50℃, 100℃, 150℃, and 200℃. Each temperature point was stabilized for 2 hours before testing. Low-temperature conditions (-20℃ to 0℃) facilitated the condensation and collection of light components in step S1, increasing the SPME extraction efficiency of S1-2 by 15-20%, but the extraction time needed to be extended to 45 minutes, and the desorption temperature adjusted accordingly to 260℃. Room temperature conditions (20-30℃) were the optimal operating range, with all technical indicators meeting the standard requirements. Medium-temperature conditions (50-100℃) accelerated solvent evaporation and good sample stability, but the extraction time needed to be shortened to 20 minutes to prevent solvent loss. High-temperature conditions (150-200℃) were suitable for special process requirements; thermal stability testing showed that triphenyl phosphate did not decompose significantly within 2 hours at 200℃, with a detection rate target >96.5%. The pressure adaptability assessment covered a pressure range of 0.1-0.5 MPa, with test pressure points set at 0.1, 0.2, 0.3, 0.4, and 0.5 MPa. Measurements were taken after each pressure point was held constant for 30 minutes. Under normal pressure (0.1 MPa), all indicators met the standard requirements. Under slightly positive pressure (0.2-0.3 MPa), the chromatographic separation efficiency of step S2 was slightly improved, with the theoretical plate number increasing by 8-12%, but the carrier gas flow rate needed to be fine-tuned to 38±2 cm / s. Under medium pressure (0.4-0.5 MPa), the column peak shape remained good, with a resolution >1.8, but the injection port pressure needed to be adjusted accordingly to 150±5 kPa, the split ratio optimized to 15:1, and the detection success rate target >97.8%. A pressure compensation algorithm was established to automatically adjust the column head pressure and carrier gas flow rate to ensure consistent separation performance under different pressures. Humidity adaptability testing was conducted with a relative humidity range of 5%-95%, with test points at 5, 15, 30, 45, 60, 75, 85, and 95%RH, and a temperature control of 25±1℃. In low-humidity environments (5-15%RH), sample volatility increased, and the SPME fiber adsorption time in S1-2 could be shortened to 25 minutes, but electrostatic protection was necessary. Moderate humidity (30-60%RH) was the optimal operating condition, with all indicators reaching their best levels. In high-humidity environments (75-95%RH), dehumidification pretreatment was required in step S1. The semiconductor refrigeration dehumidification device was set to operate at 5±1℃, with a dehumidification efficiency target of >85%, and the relative humidity reduced to below 40% after treatment. Stability and reliability data of the method under different process conditions were obtained, forming process adaptability data.

[0052] S6-3, Establish a comprehensive environmental impact assessment model, formulate operational guidelines for different application scenarios, and conduct a comprehensive analysis of process adaptability data. The composite environmental test employs an orthogonal experimental design, selecting four main factors: temperature, pressure, humidity, and fluorine interference concentration. Each factor has three levels, and an L9(3)2 model is constructed. 4 An orthogonal experimental design was used, with 9 sets of combined condition tests, each set repeated 3 times. Analysis of variance indicated that the concentration of fluorine-containing interference had the greatest impact on the detection rate, followed by temperature, while humidity and pressure had relatively smaller effects. A regression model was established: Detection rate (%) = f(C_fluorine, T, P, H), where C_fluorine is the concentration of fluorine-containing compounds (ppm), T is the temperature (°C), P is the pressure (kPa), and H is the relative humidity (%). The model parameters were determined experimentally. The extreme condition tolerance test sets challenging operating conditions: high temperature, high humidity and high interference (80℃, 90%RH, fluorine concentration 400ppm), low temperature, high pressure and low humidity (-10℃, 0.4MPa, 10%RH), and normal temperature, medium pressure and ultra-high interference (25℃, 0.3MPa, fluorine concentration 800ppm). The expected detection success rates after corresponding parameter optimization are >94%, >97%, and >92%, respectively, meeting the requirements of engineering applications. The application scenario classification guide outlines operating procedures for four typical application scenarios: Standard laboratory environments (20-25℃, 0.1MPa, 45%RH, fluorine content <50ppm) utilize standard operating procedures S1-S5, with an expected detection rate >99%; Industrial environments (10-50℃, 0.1-0.2MPa, 30-80%RH, fluorine content 50-200ppm) require temperature and humidity compensation and the moderate interference correction procedure in step S4, with an expected detection rate >97%; Special process environments (-10-100℃, 0.2-0.4MPa, 10-90%RH, fluorine content 200-500ppm) require full parameter optimization and severe interference correction in step S4, with an expected detection rate >95%; Extreme challenge environments require specialized technical support and customized parameter settings, with an expected detection rate >90%. Quality control measures include establishing standard operating procedures (SOPs) for suitability testing, conducting full-parameter suitability verification quarterly, establishing an application case database, developing contingency plans, regularly updating application guidance documents, establishing a user feedback mechanism, and archiving and storing all suitability test data; ultimately, a process suitability assessment report is generated that includes environmental suitability assessment, process condition optimization, application scenario guidance, and operating procedures.

[0053] Through systematic applicability evaluation, the reliability of the triphenyl phosphate identification method established in S1-S5 under different fluorine-containing environments and process conditions was fully verified. An operational guidance system covering four application scenarios was established, providing scientific basis and technical support for the engineering application and promotion of the method.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations will be apparent to those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for structural identification of triphenyl phosphate standard, characterized in that, Includes the following steps: Step S1 involves separating and pre-concentrating triphenyl phosphate in the sample through fluorine-containing matrix separation, target enrichment, and solvation treatment, removing fluorine-containing interfering components, enriching the target compound, and obtaining a standardized analytical sample. Step S2 involves constructing a multidimensional chromatographic system, optimizing the temperature program, and setting the carrier gas injection conditions. The standardized analytical samples are then efficiently separated using a core-cutting technique and a dual-column system to obtain high-purity triphenyl phosphate. Step S3: The structure of high-purity triphenyl phosphate is analyzed and confirmed by gas chromatography-mass spectrometry, infrared spectroscopy and nuclear magnetic resonance. The molecular structure and purity of triphenyl phosphate are verified by multi-dimensional spectral information to obtain the structurally confirmed component. Step S4: The GC-MS, FTIR, and NMR analysis data of the fully confirmed structural components are systematically identified using a five-level progressive identification algorithm, a confidence assessment system, and fluorine-containing interference correction technology, and an identification result report is obtained. Step S5 involves comprehensively evaluating the identification results report through structural integrity verification, quantitative purity assessment, and standardized report generation, establishing a confirmation standard and purity grading system for triphenyl phosphate, and finally outputting a standardized identification report. Step S6 involves systematically evaluating the applicability of the triphenyl phosphate identification method established in S1-S5 under different fluorine-containing environments and process conditions through multi-type fluorine-containing environment verification, process condition adaptability testing, and environmental tolerance evaluation. A method applicability database and application guidelines are established, and a process applicability assessment report is obtained.

2. The method for structural identification of triphenyl phosphate standard according to claim 1, characterized in that: Step S1 also includes the following sub-steps: S1-1, fluorine-containing matrix separation: the original sample is pretreated using low-temperature cold trap technology, and selective separation is achieved through a multilayer composite adsorbent system. Perfluorinated compounds are separated using liquid-liquid extraction technology to obtain the pretreated sample. S1-2, target enrichment: solid phase microextraction technology was used to enrich and concentrate triphenyl phosphate in the pretreated sample. PDMS / DVB composite coated fiber was selected as the extraction medium, and the enriched sample was obtained through thermal desorption. S1-3, Sample standardization: The enriched sample is solubilized using acetonitrile as the dissolving medium, and the internal standard diphenyl phosphate is added for quantitative correction to obtain a standardized analytical sample.

3. The method for structural identification of triphenyl phosphate standard according to claim 1, characterized in that: Step S2 also includes the following sub-steps: S2-1, Multidimensional Chromatographic Separation: A multidimensional chromatographic separation system was constructed. The RT-Q-BOND open-tube porous coated column and the DB-5MS silica capillary column were connected using the core-cutting technique to perform preliminary separation of standardized analytical samples and obtain preliminary separated components. S2-2, programmed temperature rise fine separation, optimizes programmed temperature rise conditions to achieve staged separation of different components. The system is preheated to -20℃ and then heated to 300℃ according to the set gradient. The initially separated components are finely processed to obtain separated and purified components. S2-3, Carrier Gas Optimization and Component Collection: High-purity helium was used as the carrier gas. Through programmed temperature vaporization technology and a split / splitless combined strategy, high-purity triphenyl phosphate was obtained by precise collection within the retention time window of triphenyl phosphate.

4. The method for structural identification of triphenyl phosphate standard according to claim 1, characterized in that: Step S3 also includes the following sub-steps: S3-1, Gas Chromatography-Mass Spectrometry Structure Analysis: The structure of high-purity triphenyl phosphate was analyzed using a GC-MS system. Characteristic ions were detected by full scan mode and selected ion monitoring mode to confirm molecular ion peaks and characteristic fragment ions, and mass spectrometry-confirmed components were obtained. S3-2, Infrared Spectroscopic Structure Confirmation: Attenuated total reflectance Fourier transform infrared spectroscopy was used to confirm the structure of the mass spectrometry-confirmed components, identifying the characteristic absorption of the P=O stretching vibration peak, the benzene ring skeleton vibration peak, and the POC stretching vibration peak to obtain the infrared-confirmed components. S3-3, Precise Structure Identification by Nuclear Magnetic Resonance: This method uses nuclear magnetic resonance (NMR) technology to perform precise structural identification of components confirmed by infrared spectroscopy. 31 P NMR, 1 H NMR and 13 C10 NMR testing confirmed the molecular structure and chemical environment, obtaining the fully confirmed components.

5. The method for structural identification of triphenyl phosphate standard according to claim 1, characterized in that: Step S4 also includes the following sub-steps: S4-1, Construction of a five-level progressive identification algorithm: A five-level progressive identification algorithm system is constructed to verify the structurally fully confirmed components step by step in the order of GC-MS-IR-NMR. Preliminary identification results are obtained through retention time screening, molecular ion peak confirmation, fragment mode matching, IR characteristic peak verification, and NMR chemical shift confirmation. S4-2, Confidence Assessment and Interference Correction: Establish an identification confidence assessment system, conduct a comprehensive assessment based on the quantity and quality of the identification levels passed, and use fluorine-containing interference assessment and correction algorithms to obtain an identification result report.

6. The method for structural identification of triphenyl phosphate standard according to claim 1, characterized in that: Step S5 also includes the following sub-steps: S5-1, Structural integrity judgment criteria: Establish structural integrity judgment criteria, use multidimensional spectral data to cross-verify the molecular structure of the target compound, establish a structural integrity scoring system through molecular ion peak verification, functional group integrity test and nuclear magnetic resonance verification, and obtain structural confirmation results; S5-2, Purity Quantitative Assessment Standard: Establish a purity quantitative assessment standard, adopt a combined quantitative analysis of chromatographic purity determination, mass spectrometry purity calculation and nuclear magnetic resonance purity determination, establish a purity grading standard, and obtain purity assessment results; S5-3, Standardized Appraisal Report Output: Design a standardized appraisal report output system, establish a unified report format and judgment criteria, including qualitative conclusions, confidence level ratings, interference assessments, and recommended measures, and output standardized appraisal reports.

7. The method for structural identification of triphenyl phosphate standard according to claim 1, characterized in that: Step S6 also includes the following sub-steps: S6-1, Verification of environmental suitability for multiple fluorine-containing environments: Constructing multiple fluorine-containing environment simulation systems, evaluating the detection performance of the method under interference from different fluorine-containing compounds such as HFCs, PFCs, SF6 and methane, and forming an environmental suitability database; S6-2, Process condition adaptability assessment: Establish a multi-parameter process condition testing platform to comprehensively evaluate the stability and reliability of the method under different temperature, pressure, and humidity conditions, and generate process adaptability data. S6-3, Comprehensive Applicability Assessment and Application Guidance: Establish a comprehensive environmental factor impact assessment model, formulate operational guidelines for different application scenarios, conduct extreme condition tolerance tests, and generate a process applicability assessment report.

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