Phosphate fire-resistant oil component analysis method based on microwave digestion

Abstract

The invention relates to the field of phosphate fire-resistant oil analysis, in particular to a phosphate fire-resistant oil component analysis method based on microwave digestion. The method specifically comprises the following steps: putting phosphate fire-resistant oil, deionized water and a digestion solution into a microwave reactor, carrying out digestion reaction, adding acid into the completely digested liquid, and acidifying the reacted solution until the pH value of the solution is not greater than 3; adding an organic solvent to extract the phenolic compound in the solution, and removing the organic solvent in the extract to obtain the phenolic compound; the method comprises the following steps: carrying out liquid chromatography detection and nuclear magnetic resonance hydrogen spectrum detection on a phenolic compound to obtain a phenolic compound detection result after phosphate ester decomposition, and determining corresponding phosphate ester components and structures; the method has the characteristics of short detection period and high accuracy.

Description

Technical Field

[0001] The invention relates to the field of phosphate fire-resistant oil analysis, and in particular to a phosphate fire-resistant oil component analysis method based on microwave digestion. Background Art

[0002] With the rapid development of the electric power industry, the safe and stable operation of power generation steam turbine units as core power equipment is directly related to the reliability and economy of the power grid. As a high-performance hydraulic working medium, phosphate ester fire-resistant oil plays an indispensable role in the speed control system of power generation steam turbine units due to its high auto-ignition point, excellent lubrication performance and excellent chemical stability. The core component of this fire-resistant oil, triaryl phosphate, directly determines the operating efficiency and safety of the entire speed control system.

[0003] However, the current detection and analysis technology of phosphate fire-resistant oils faces many challenges. First, the raw materials for the synthesis of triaryl phosphates are mainly derived from phenolic compounds extracted from coal tar. These raw materials often contain a variety of impurities and isomers, resulting in the final synthesized triaryl phosphates not being a single compound, but a complex mixture. The complexity of this component brings great difficulty to the detection and analysis. There are significant differences between the products synthesized from different batches of raw materials, making it difficult to ensure the stability and consistency of product quality.

[0004] Secondly, existing detection methods such as chromatography and mass spectrometry have limitations in directly detecting triaryl phosphate components in phosphate fire-resistant oils. Due to the wide variety of phosphates, especially complex structures such as tri-(dimethylphenyl) phosphate, direct analysis often makes it difficult to obtain accurate and comprehensive component information. In addition, these methods have high equipment requirements, complex operations, and may be affected by factors such as sample pretreatment, resulting in limited accuracy and reliability of the test results.

[0005] In order to overcome these difficulties, some researchers have proposed the hydrolysis method as an alternative. This method hydrolyzes phosphate esters to convert them into easily detectable phenolic compounds, and then infers the structure and composition of phosphate esters by detecting the type and content of phenolic compounds. Although this method improves the accuracy of detection to a certain extent, the hydrolysis process is time-consuming, usually requiring 24 hours or even longer, which seriously affects the detection efficiency and is difficult to meet the needs of modern industrial production for rapid and efficient detection. Summary of the invention

[0006] The purpose of the present invention is to solve the problems of long detection period and low detection efficiency of phosphate fire-resistant oil components in the above-mentioned prior art, and to propose a phosphate fire-resistant oil component analysis method based on microwave digestion.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a method for analyzing components of phosphate fire-resistant oil based on microwave digestion, which specifically comprises the following steps: The phosphate fire-resistant oil, deionized water and digestion solution are placed in a microwave reactor to perform a digestion reaction, and an acid is added to the liquid after the digestion is completed to acidify the solution after the reaction until the pH value of the solution is not greater than 3; An organic solvent is added to extract phenolic compounds in a solution, and the organic solvent in the extract is removed to obtain phenolic compounds; liquid chromatography detection and nuclear magnetic resonance hydrogen spectrum detection are carried out on the phenolic compounds to obtain detection results of the phenolic compounds after phosphate decomposition, and the corresponding phosphate components and structures are determined.

[0008] Preferably, the specific method of the reaction digestion is: Part of the liquid in the microwave reactor is taken for thin layer chromatography analysis and detection. If it is detected that the triaryl phosphate still remains in the liquid, the digestion is continued until the triaryl phosphate is completely decomposed.

[0009] Preferably, the specific method of the thin layer chromatography analysis and detection is: dissolving the extracted liquid in ethyl acetate to obtain a triaryl phosphate sample, using a mixed solution of dichloromethane and methanol as a developing agent and spotting the triaryl phosphate sample on a silica gel plate at the same time, and comparing the ratio transfer values ​​after development; if there are points with the same ratio transfer value between the two, it indicates that the digestion is not complete, and then continue digestion until there are no points with the same ratio transfer value.

[0010] Preferably, the mass ratio of dichloromethane to methanol is 2:1.

[0011] Preferably, the mass ratio of the phosphate fire-resistant oil, deionized water and digestion solution is 1:1:(3-5).

[0012] Preferably, the digestion solution is a NaOH solution or a KOH solution.

[0013] Preferably, the concentration of the NaOH solution or KOH solution is 5% to 15%.

[0014] Preferably, the acid is 0.5-1.5 mol / L hydrochloric acid or sulfuric acid.

[0015] Preferably, the organic solvent is one or two of petroleum ether, chloroform and diethyl ether.

[0016] Preferably, the liquid chromatography detection refers to the use of a chiral chromatographic column; wherein the mass ratio of the mobile phase cyclohexane to methanol is 95:5, and the flow rate is 1.5 mL / min.

[0017] Compared with the prior art, the present invention has the following beneficial effects: In the present invention, microwave digestion is performed by adding a digestion solution, so that the decomposition process of the phosphate ester can be accelerated; the pH value of the solution is adjusted to no more than 3, which is conducive to the effective separation of phenolic compounds in the subsequent extraction process and reduces the interference of other non-target compounds; the phenolic compounds are extracted by an organic solvent, so that the target compounds can be efficiently separated from the complex system and the accuracy of detection is improved; the liquid chromatography detection can efficiently separate and detect the phenolic compounds after the decomposition of the phosphate ester and provide detailed compound composition information; the nuclear magnetic resonance hydrogen spectrum detection can accurately determine the type and quantity of hydrogen atoms in the compound, and combined with the liquid chromatography result, the specific composition and structure of the phosphate ester can be accurately inferred.

[0018] The present invention can quickly decompose triaryl phosphate into phenolate based on microwave digestion reaction, obtain phenolic compounds after acidification, obtain the structure and content of phenolic compounds based on nuclear magnetic resonance hydrogen spectrum and liquid chromatography detection, and reversely obtain the components and structure of phosphate fire-resistant oil. Compared with the common hydrolysis method, this method can improve the detection efficiency and shorten the detection cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a liquid phase chromatogram of the phosphate fire-resistant oil in Example 1 of the present invention; Figure 2 The nuclear magnetic resonance phosphorus spectrum of the phosphate fire-resistant oil in Example 1 of the present invention; Figure 3 This is a liquid chromatogram of the phosphate fire-resistant oil (after digestion) in Example 1 of the present invention; Figure 4 This is the nuclear magnetic hydrogen spectrum of the phosphate fire-resistant oil (after digestion) in Example 1 of the present invention; Figure 5 is the liquid chromatogram of phenol standard; Figure 6 is a liquid chromatogram of 2,3-dimethylphenol standard; Figure 7 is a liquid chromatogram of 2,4-dimethylphenol standard; Figure 8 is a liquid chromatogram of 2,5-dimethylphenol standard; Fig. 9 is a liquid chromatogram of 2,6-dimethylphenol standard; Fig.10 is a liquid chromatogram of 3,4-dimethylphenol standard; Fig.11 is a liquid chromatogram of 3,5-dimethylphenol standard; Fig.12 is the liquid chromatogram of 2-ethylphenol standard; Fig.13 is the liquid chromatogram of 3-ethylphenol standard; Fig.14 This is the liquid chromatogram of 4-ethylphenol standard. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0021] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0022] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0023] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0024] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0025] The present invention is further described in detail below in conjunction with the accompanying drawings: The present invention provides a method for analyzing components of phosphate fire-resistant oil based on microwave digestion, which specifically comprises the following steps: The phosphate fire-resistant oil, deionized water and digestion solution are placed in a microwave reactor to perform a digestion reaction, and an acid is added to the liquid after the digestion is completed to acidify the solution after the reaction until the pH value of the solution is not greater than 3; An organic solvent is added to extract phenolic compounds in a solution, and the organic solvent in the extract is removed to obtain phenolic compounds; liquid chromatography detection and nuclear magnetic resonance hydrogen spectrum detection are carried out on the phenolic compounds to obtain detection results of the phenolic compounds after phosphate decomposition, and the corresponding phosphate components and structures are determined.

[0026] The specific method of reaction digestion is: taking part of the liquid in the microwave reactor for thin layer chromatography analysis and detection, if it is detected that triaryl phosphate still remains in the liquid, then continue digestion until the triaryl phosphate is completely decomposed; the specific method of thin layer chromatography analysis and detection is: dissolving the taken liquid in ethyl acetate to obtain a triaryl phosphate sample, using a mixed solution of dichloromethane and methanol as a developing agent and spotting the triaryl phosphate sample on a silica gel plate at the same time, and comparing the ratio transfer values ​​after development; if there are points with the same ratio transfer value between the two, it indicates that the digestion is not complete, and then continue digestion until there are no points with the same ratio transfer value.

[0027] The specific method for obtaining the detection results of phenolic compounds after phosphate decomposition and determining the corresponding phosphate components and structures is as follows: combining the detection results, obtaining the liquid chromatogram and nuclear magnetic resonance hydrogen spectrum of the phenolic compounds after digestion; comparing the peak value with the spectra of dozens of methyl and ethyl phenol standards ( Figures 5 to 14 ) to find the same peaks, and determine the phenolic substances after sample digestion based on the phenolic substances corresponding to the peaks of the standard spectrum, and then determine the corresponding phosphate components and structures.

[0028] In the present invention, microwave digestion is performed by adding a digestion solution, so that the decomposition process of the phosphate ester can be accelerated; the pH value of the solution is adjusted to no more than 3, which is helpful for the effective separation of phenolic compounds in the subsequent extraction process and reduces the interference of other non-target compounds; the phenolic compounds are extracted by an organic solvent, so that the target compounds can be efficiently separated from the complex system and the detection accuracy is improved; the thin layer chromatography analysis can monitor the residual situation of the triaryl phosphate ester in the digestion process in real time and provide an intuitive basis for whether the digestion reaction is complete; by comparing the ratio shift value, it can be accurately judged whether the digestion is thorough and the analysis error caused by incomplete digestion is avoided; the liquid chromatography detection can efficiently separate and detect the phenolic compounds after the decomposition of the phosphate ester and provide detailed compound composition information; the nuclear magnetic resonance hydrogen spectrum detection can accurately determine the type and quantity of hydrogen atoms in the compound, and combined with the liquid chromatography result, the specific composition and structure of the phosphate ester can be accurately inferred.

[0029] In addition, the mass ratio of dichloromethane to methanol is 2:1, and this ratio enables the mixed solvent to have appropriate polarity and volatility in thin layer chromatography analysis, and can effectively develop and separate different components in the sample; the mixed solvent of dichloromethane and methanol has good selectivity for phosphate esters and their decomposition products, which helps to reduce background interference and improve detection accuracy.

[0030] The mass ratio of the phosphate fire-resistant oil, deionized water and digestion solution is 1:1:(3-5); this ratio ensures that the digestion reaction is carried out within an appropriate concentration range, which is neither too diluted nor too concentrated, and is conducive to the full decomposition of the phosphate ester; in actual operation, it can be adjusted according to specific samples and experimental conditions to achieve the best digestion effect.

[0031] The digestion solution has a concentration of 5% to 15% NaOH solution or KOH solution; both NaOH and KOH are strong bases, which can provide a sufficient alkaline environment in a wide concentration range to promote the digestion reaction of phosphate esters, and are relatively stable in the solution, not easy to decompose or produce other by-products, which is conducive to maintaining the purity of the reaction system. The adjustability of the concentration between 5% and 15% allows the selection of a suitable concentration according to sample characteristics and experimental requirements to achieve the best digestion effect.

[0032] The acid is 0.5-1.5 mol / L hydrochloric acid or sulfuric acid. Acids in this concentration range can effectively acidify the digested solution to the desired pH value (not greater than 3), which is beneficial to the subsequent extraction and detection steps; and hydrochloric acid and sulfuric acid are both commonly used inorganic strong acids, easy to obtain and relatively cheap.

[0033] The organic solvent is one or two of petroleum ether, chloroform and ether, which can efficiently and selectively extract phenolic compounds in the solution after the digestion of phosphate fire-resistant oil, and improve the extraction efficiency and purity by covering target objects of different polarities. At the same time, these organic solvents are relatively low in toxicity, easy to recycle and treat, and comply with the principles of green chemistry. The combined use of these organic solvents can further enhance the comprehensiveness and flexibility of the extraction.

[0034] The liquid chromatography detection refers to the use of a chiral chromatographic column; wherein the mass ratio of mobile phase cyclohexane to methanol is 95:5, and the flow rate is 1.5 mL / min. The chiral chromatographic column can distinguish enantiomers, and has a unique separation ability for phosphate decomposition products containing chiral centers, thereby improving the accuracy and sensitivity of the detection; under the combined effect of the ratio of mobile phase cyclohexane to methanol (95:5) and the appropriate flow rate (1.5 mL / min), the liquid chromatography detection has a high resolution and can clearly separate the various components in the sample; the mobile phase system has good stability on the chromatographic column, is not easy to cause contamination or damage to the chromatographic column, and prolongs the service life of the chromatographic column.

[0035] The invention can rapidly decompose triaryl phosphate into phenolate based on microwave digestion reaction, obtain phenolic compounds after acidification, obtain the structure and content of phenolic compounds based on nuclear magnetic resonance hydrogen spectrum and liquid chromatography detection, and reversely obtain the components and structure of phosphate fire-resistant oil. The whole process takes about one hour, and the digestion method takes at least 48 hours. Compared with the common digestion method, the method of the invention can improve the detection efficiency and significantly shorten the detection period.

[0036] Example 1 First, 10.0g of phosphate fire-resistant oil sample, 10.0g of deionized water and 30.0g of 10% NaOH solution were placed in a microwave reactor at 1500W power for 30min before digestion. A small amount of 0.5ml of liquid was dissolved in ethyl acetate, and a mixed solution of dichloromethane and methanol (mixed ratio of dichloromethane to methanol was 2:1) was used as the developing solvent for thin layer chromatography analysis. If no sample with the same ratio transfer value as the triaryl phosphate sample was detected, the triaryl phosphate had been completely decomposed. If a sample with the same ratio transfer value as the triaryl phosphate sample was detected, the digestion was continued until the triaryl phosphate was completely decomposed. 0.5mol / L hydrochloric acid was added to the digested liquid to acidify the reaction solution until the pH was no greater than 3. 50mL of petroleum ether was added each time to extract the phenolic compounds in the solution, and the extraction was performed three times to obtain a total of about 150mL of extract. The petroleum ether in the extract was removed by a rotary evaporator to obtain a phenolic mixture. Liquid chromatography and nuclear magnetic resonance hydrogen spectrum detection were carried out on the phenol mixture. The liquid chromatography detection used a chiral chromatographic column, the mass ratio of cyclohexane to methanol of the mobile phase was 95:5, and the flow rate was 1.5 mL / min. The detection results of phenolic compounds after phosphate decomposition were obtained, and the corresponding phosphate composition and structure were deduced based on the detection results.

[0037] like Figure 1 and Figure 2 As shown, the liquid chromatography and nuclear magnetic resonance phosphorus spectra of the phosphate fire-resistant oil sample of Example 1 both contain dozens of peaks, indicating that the sample contains dozens of phosphate molecules with different structures, and the polarities of different types of phosphate molecules are relatively close. There is a certain degree of cross-overlap between different peaks in the liquid chromatogram, and the components cannot be accurately determined. Therefore, the phosphate structure cannot be directly analyzed.

[0038] The test results of Example 1 are as follows Figure 3 and Figure 4 As shown, Figure 3 and Figure 4 The following are the liquid chromatography and nuclear magnetic resonance hydrogen spectra of phenolic compounds after microwave digestion. Figure 3It can be seen that the liquid chromatogram after microwave digestion contains 6 peaks, indicating that the phenol mixture contains 6 phenol compounds with different structures. Combined with the results of nuclear magnetic resonance hydrogen spectrum, compared with the spectra of dozens of methyl and ethyl phenol standards, such as Figures 5 to 14 As shown, the phenolic substances after the sample digestion were determined to contain 3-ethylphenol, 4-ethylphenol, 3,5-dimethylphenol, 2,3-dimethylphenol, 2,4-dimethylphenol and 2,5-dimethylphenol, and the contents were 22.51%, 20.88%, 2.38%, 18.00%, 22.60% and 13.63% respectively. It was deduced that the phosphate fire-resistant oil component was mainly tri-(dimethylphenyl) phosphate, and was mixed with some tri-(ethylphenyl) phosphate, (ethyl-dimethyl) phenyl phosphate or (diethyl-methyl) phenyl phosphate; in addition, the content of dimethylphenol, especially 3,5-dimethylphenol, should be increased as much as possible during the production process.

[0039] Example 2 First, 10.0g of phosphate fire-resistant oil sample, 10.0g of deionized water and 35.0g of 5% NaOH solution were placed in a microwave reactor at 1500W power and the digestion was stopped after 30min of reaction. A small amount of 0.5ml of liquid was dissolved in ethyl acetate and a mixed solution of dichloromethane and methanol (the mixing ratio of dichloromethane to methanol was 2:1) was used as the developing agent for thin layer chromatography analysis. If no sample with the same ratio transfer value as the triaryl phosphate sample was detected, the triaryl phosphate had been completely decomposed. If a sample with the same ratio transfer value as the triaryl phosphate sample was detected, the digestion was continued until the triaryl phosphate was completely decomposed. 1.0mol / L hydrochloric acid was added to the digested liquid to acidify the reaction solution until the pH was no greater than 3. 50mL of chloroform was added each time to extract the phenolic compounds in the solution, and the extraction was performed three times to obtain a total of about 150mL of extract. The chloroform in the extract was removed by a rotary evaporator to obtain a phenolic mixture. Liquid chromatography and nuclear magnetic resonance hydrogen spectrum detection were carried out on the phenol mixture. The liquid chromatography detection used a chiral chromatographic column, the mass ratio of cyclohexane to methanol of the mobile phase was 95:5, and the flow rate was 1.5 mL / min. The detection results of phenolic compounds after phosphate decomposition were obtained, and the corresponding phosphate composition and structure were deduced based on the detection results.

[0040] Example 3 First, 10.0g of phosphate fire-resistant oil sample, 10.0g of deionized water and 40.0g of 15% NaOH solution were placed in a microwave reactor at 1500W power for 30min before digestion. A small amount of 0.5ml of liquid was dissolved in ethyl acetate, and a mixed solution of dichloromethane and methanol (mixed ratio of dichloromethane to methanol was 2:1) was used as the developing agent for thin layer chromatography analysis. If no sample with the same ratio transfer value as the triaryl phosphate sample was detected, the triaryl phosphate had been completely decomposed. If a sample with the same ratio transfer value as the triaryl phosphate sample was detected, the digestion was continued until the triaryl phosphate was completely decomposed. 1.5mol / L hydrochloric acid was added to the digested liquid to acidify the post-reaction solution until the pH was no greater than 3. 50mL of ether was added each time to extract the phenolic compounds in the solution, and the extraction was performed three times to obtain a total of about 150mL of extract. The ether in the extract was removed by a rotary evaporator to obtain a phenolic mixture. Liquid chromatography and nuclear magnetic resonance hydrogen spectrum detection were carried out on the phenol mixture. The liquid chromatography detection used a chiral chromatographic column, the mass ratio of cyclohexane and methanol of the mobile phase was 95:5, and the flow rate was 1.5mL / min. The detection results of phenolic compounds after phosphate decomposition were obtained, and the corresponding phosphate ester composition and structure were deduced based on the detection results.

[0041] Example 4 First, 10.0g of phosphate fire-resistant oil sample, 10.0g of deionized water and 45.0g of 5% KOH solution were placed in a microwave reactor at 1500W power for 30min before digestion. A small amount of 0.5ml of liquid was dissolved in ethyl acetate, and a mixed solution of dichloromethane and methanol (mixed ratio of dichloromethane to methanol was 2:1) was used as a developing agent for thin layer chromatography analysis. If no sample with the same ratio transfer value as the triaryl phosphate sample was detected, the triaryl phosphate had been completely decomposed. If a sample with the same ratio transfer value as the triaryl phosphate sample was detected, the digestion was continued until the triaryl phosphate was completely decomposed. 0.5mol / L sulfuric acid was added to the digested liquid to acidify the post-reaction solution until the pH was no greater than 3. 50mL of a mixed solution of petroleum ether and chloroform was added each time to extract phenolic compounds in the solution, and the extraction was performed three times to obtain a total of about 150mL of extract. A rotary evaporator was used to remove the mixture of petroleum ether and chloroform in the extract to obtain a phenol mixture. Liquid chromatography and nuclear magnetic resonance hydrogen spectrum detection were carried out on the phenol mixture. The liquid chromatography detection used a chiral chromatographic column, the mass ratio of cyclohexane to methanol of the mobile phase was 95:5, and the flow rate was 1.5 mL / min; the detection results of phenol compounds after phosphate decomposition were obtained, and the corresponding phosphate components and structures were deduced based on the detection results.

[0042] Example 5 First, 10.0g of phosphate fire-resistant oil sample, 10.0g of deionized water and 50.0g of 15% KOH solution were placed in a microwave reactor at 1500W power for 30min before digestion. A small amount of 0.5ml of liquid was dissolved in ethyl acetate, and a mixed solution of dichloromethane and methanol (mixed ratio of dichloromethane to methanol was 2:1) was used as the developing agent for thin layer chromatography analysis. If no sample with the same ratio transfer value as the triaryl phosphate sample was detected, the triaryl phosphate had been completely decomposed. If a sample with the same ratio transfer value as the triaryl phosphate sample was detected, the digestion was continued until the triaryl phosphate was completely decomposed. 1.0mol / L sulfuric acid was added to the digested liquid to acidify the post-reaction solution until the pH was no greater than 3. 50mL of chloroform and ether were added each time to extract the phenolic compounds in the solution, and the extraction was performed three times to obtain a total of about 150mL of extract. A rotary evaporator was used to remove the mixture of chloroform and ether in the extract to obtain a phenol mixture. The phenol mixture was subjected to liquid chromatography and nuclear magnetic resonance hydrogen spectrum detection. The liquid chromatography detection used a chiral chromatographic column, the mass ratio of cyclohexane to methanol of the mobile phase was 95:5, and the flow rate was 1.5 mL / min; the detection results of phenol compounds after phosphate decomposition were obtained, and the corresponding phosphate components and structures were deduced based on the detection results.

[0043] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for analyzing the components of phosphate fire-resistant oils based on microwave digestion, characterized in that: The specific steps include: The phosphate fire-resistant oil, deionized water and digestion solution are placed in a microwave reactor to perform a digestion reaction, and an acid is added to the liquid after the digestion is completed to acidify the solution after the reaction until the pH value of the solution is not greater than 3; adding an organic solvent to extract the phenolic compound in the solution, removing the organic solvent in the extract, and obtaining the phenolic compound; Liquid chromatography and nuclear magnetic resonance hydrogen spectrum detection were carried out on phenolic compounds to obtain the detection results of phenolic compounds after phosphate decomposition, and to determine the corresponding phosphate composition and structure.

2. The method for analyzing the components of phosphate fire-resistant oils based on microwave digestion according to claim 1, characterized in that: The specific method of the reaction digestion is: Part of the liquid in the microwave reactor is taken for thin layer chromatography analysis and detection. If it is detected that the triaryl phosphate still remains in the liquid, the digestion is continued until the triaryl phosphate is completely decomposed.

3. The method for analyzing the components of phosphate fire-resistant oils based on microwave digestion according to claim 2, characterized in that: The specific method of the thin layer chromatography analysis and detection is: dissolving the extracted liquid in ethyl acetate to obtain a triaryl phosphate sample, using a mixed solution of dichloromethane and methanol as a developing agent and spotting the triaryl phosphate sample on a silica gel plate at the same time, and comparing the relative transfer values ​​after development; if there are points with the same relative transfer value between the two, it indicates that the digestion is not complete, and then continue to digest until there are no points with the same relative transfer value.

4. The method for analyzing the components of phosphate fire-resistant oils based on microwave digestion according to claim 3, characterized in that: The mass ratio of dichloromethane to methanol is 2:

1.

5. The method for analyzing the components of phosphate fire-resistant oils based on microwave digestion according to claim 1, characterized in that: The mass ratio of the phosphate fire-resistant oil, deionized water and digestion solution is 1:1:(3-5).

6. The method for analyzing the components of phosphate fire-resistant oils based on microwave digestion according to claim 1, characterized in that: The digestion solution is a NaOH solution or a KOH solution.

7. The method for analyzing the components of phosphate fire-resistant oils based on microwave digestion according to claim 6, characterized in that: The concentration of the NaOH solution or KOH solution is 5% to 15%.

8. The method for analyzing the components of phosphate fire-resistant oils based on microwave digestion according to claim 1, characterized in that: The acid is 0.5-1.5 mol / L hydrochloric acid or sulfuric acid.

9. The method for analyzing the components of phosphate fire-resistant oils based on microwave digestion according to claim 1, characterized in that: The organic solvent is one or two of petroleum ether, chloroform and ether.

10. The method for analyzing the components of phosphate fire-resistant oils based on microwave digestion according to claim 1, characterized in that: The liquid chromatography detection refers to the use of a chiral chromatographic column; wherein the mass ratio of the mobile phase cyclohexane to methanol is 95:5, and the flow rate is 1.5 mL / min.

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