A method for effectively removing phenolic compounds from triaryl phosphates

Abstract

The invention belongs to the field of phosphate fire-resistant oils, and specifically relates to a method for effectively removing phenolic compounds in triaryl phosphate. The method specifically comprises the following steps: dissolving aluminum phosphate in an organic solvent, adding a carrier with a porous structure after mixing and stirring, removing the organic solvent after mixing, and obtaining a modified adsorbent; mixing the modified adsorbent with the triaryl phosphate at 40-60 DEG C, so that the modified adsorbent adsorbs the phenolic compounds in the triaryl phosphate, filtering and removing the modified adsorbent after sufficient adsorption, and obtaining the triaryl phosphate after the phenolic compounds are removed; the method can specifically remove free phenol in phosphate, and significantly improve the adsorption capacity of the modified adsorbent for free phenol; the free phenol content of the triaryl phosphate after adsorption treatment is significantly reduced, and the oxidation stability index is improved.

Description

Technical Field

[0001] The invention belongs to the field of phosphate fire-resistant oils, and in particular relates to a method for effectively removing phenolic compounds in triaryl phosphate. Background Art

[0002] Phosphate fire-resistant oil has excellent flame retardant, anti-wear and oxidation stability, and is often used as a hydraulic working medium in the turbine speed control system of a generator set. The main component of phosphate fire-resistant oil is triaryl phosphate, which plays a decisive role in the performance of fire-resistant oil. Triaryl phosphate mainly adopts the following two synthesis methods. The first is to use phosphorus oxychloride and phenolic compounds as raw materials, and obtain a crude triaryl phosphate product through chlorination and acidification reaction; the second is to use phosphorus oxychloride and phenolic compounds as raw materials to synthesize the crude triaryl phosphate product in one step, and the crude product is washed with alkali and distilled to obtain a triaryl phosphate with high purity. Although this process can effectively remove most of the by-products and impurities, some phenols will still remain in the phosphate. If this is used as a raw material for the base oil of phosphate fire-resistant oil, it will affect the antioxidant performance of phosphate fire-resistant oil, accelerate the darkening of the oil color, shorten the service life of the fire-resistant oil, and affect the safe and stable operation of the unit. Therefore, it is necessary to remove free phenol in triaryl phosphate.

[0003] At present, the common methods for removing free phenol are alkali washing and adsorption. The alkali washing method is to wash the triaryl phosphate with a dilute alkali solution, so that the alkali reacts with phenol to form phenol salt, and then obtain the phosphate fire-resistant oil base oil through extraction, distillation and other processes. However, this method has complicated steps, high energy consumption, and requires a large amount of organic solvent, which has an impact on the environment. Another method is the adsorption method, that is, diatomaceous earth is used to adsorb the triaryl phosphate to remove the phenolic compounds therein. However, because the modified adsorbent cannot carry out specific adsorption of phenolic compounds, the adsorption effect is poor and the free phenol therein cannot be effectively removed. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a method for effectively removing phenolic compounds in triaryl phosphates, which can effectively remove free phenol, modify common modified adsorbents, improve the adsorption performance of the modified adsorbents for free phenol, and improve the stability of phosphate fire-resistant oil base oil; the method is simple to operate, does not require the use of a large amount of organic solvents, and is environmentally friendly.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a method for effectively removing phenolic compounds in triaryl phosphate, which specifically comprises the following steps:

[0007] Aluminum phosphate is dissolved in an organic solvent, mixed and stirred, and then a carrier with a porous structure is added, and the organic solvent is removed after mixing to obtain a modified adsorbent;

[0008] The modified adsorbent and the triaryl phosphate are mixed and stirred at 40-60° C., so that the modified adsorbent adsorbs the phenolic compounds in the triaryl phosphate, and after sufficient adsorption, the modified adsorbent is removed by filtering to obtain the triaryl phosphate after the phenolic compounds are removed;

[0009] The solid-liquid ratio of the aluminum phosphate and the organic solvent is 1 g: (10-50) mL; the mass ratio of the aluminum phosphate and the carrier with a porous structure is 1: (3-6).

[0010] Preferably, the carrier with a porous structure is β zeolite, silica gel or diatomaceous earth.

[0011] Preferably, the particle size of the silica gel is 200-400 mesh.

[0012] Preferably, the mass of the modified adsorbent is 4% to 8% of the mass of the triaryl phosphate.

[0013] Preferably, the organic solvent is methanol, ethanol or propanol.

[0014] Preferably, the modified adsorbent and the triaryl phosphate are mixed and stirred for 1 to 4 hours.

[0015] Preferably, the porosity of the modified adsorbent is not less than 50%.

[0016] Preferably, the mixing and stirring is carried out by magnetic stirring or mechanical stirring.

[0017] Preferably, the mixing and stirring speed is 800-1200 r / min.

[0018] Preferably, the organic solvent is removed by evaporation after mixing.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention adopts a carrier with a porous structure, which provides abundant sites for the loading of aluminum phosphate with its unique pore structure and huge specific surface area, greatly enhances the adsorption capacity of the adsorbent, and enables the modified adsorbent to more effectively capture and remove free phenol in the triaryl phosphate when treating the triaryl phosphate, significantly reduces the free phenol content, and improves the purity of the product; the complex reaction between aluminum ions and free phenol is highly selective, and the free phenol in the phosphate is removed in a targeted manner by utilizing the complex reaction between aluminum ions and free phenol, significantly enhancing the adsorption capacity of the modified adsorbent for free phenol, thereby significantly improving the oxidation stability of the triaryl phosphate treated by the modified adsorbent. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only embodiments of a part of the present invention, not all 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] The present invention provides a method for effectively removing phenolic compounds in triaryl phosphate, which specifically comprises the following steps:

[0026] Aluminum phosphate is dissolved in an organic solvent, mixed and stirred, and then a carrier with a porous structure is added, and the organic solvent is removed after mixing to obtain a modified adsorbent;

[0027] The modified adsorbent and the triaryl phosphate are mixed and stirred at 40-60° C., so that the modified adsorbent adsorbs the phenolic compounds in the triaryl phosphate, and after sufficient adsorption, the modified adsorbent is removed by filtering to obtain the triaryl phosphate after the phenolic compounds are removed;

[0028] The solid-liquid ratio of the aluminum phosphate and the organic solvent is 1 g: (10-50) mL; the carrier with a porous structure is β-zeolite, silica gel or diatomaceous earth; the mass ratio of the aluminum phosphate and the carrier with a porous structure is 1: (3-6); the mass of the modified adsorbent is 4%-8% of the mass of the triaryl phosphate.

[0029] The present invention adds a carrier with a porous structure into an aluminum phosphate solution and mixes them fully, so that the aluminum phosphate can adhere to the surface of the carrier with a porous structure or enter the pores thereof to form a modified adsorbent. Through an evaporation process, the organic solvent is effectively removed, leaving the modified adsorbent in which the aluminum phosphate is tightly combined with the carrier with a porous structure. When the modified adsorbent and the triaryl phosphate are mixed and stirred, the aluminum ions on the modified adsorbent can undergo a complex reaction with free phenol, thereby adsorbing the free phenol on the modified adsorbent, and the free phenol in the triaryl phosphate is removed in a targeted manner, thereby significantly improving the adsorption capacity of the modified adsorbent for the free phenol, significantly reducing the free phenol content of the triaryl phosphate after adsorption treatment, and improving the oxidation stability index.

[0030] The modified adsorbent and triaryl phosphate are mixed and stirred at 40-60°C, so that the modified adsorbent adsorbs the phenolic compounds in the triaryl phosphate. The temperature range of 40-60°C is an effective temperature range for many adsorption processes, which can not only ensure a high adsorption rate, but also avoid adverse effects on the adsorbent or adsorbate; and helps to keep the active sites of the adsorbent intact, thereby ensuring its efficient adsorption of phenolic compounds, and also helps to reduce the volatilization loss of phenolic compounds.

[0031] Illustratively, in the above scheme, the removal of the organic solvent in the present invention makes the interaction between aluminum phosphate and the carrier with a porous structure more solid, which helps to maintain the porous structure and adsorption performance of the modified adsorbent; carriers such as β-zeolite, silica gel or diatomaceous earth have a large specific surface area and pore structure, which can provide abundant adsorption sites, promote the diffusion and adsorption of the adsorbate inside the adsorbent, and improve the adsorption efficiency.

[0032] Wherein, the organic solvent is methanol, ethanol or propanol; the particle size of the silica gel is 200 mesh to 400 mesh; the time for mixing and stirring the modified adsorbent and triaryl phosphate is 1 to 4 hours; the porosity of the modified adsorbent is not less than 50%; the mixing and stirring adopts magnetic stirring or mechanical stirring; the rotation speed of the mixing and stirring is 800 to 1200 r / min; and the organic solvent is removed by evaporation after mixing.

[0033] For example, in the above scheme, methanol, ethanol and propanol as organic solvents have good solubility for a variety of substances, which helps to evenly disperse aluminum phosphate in the solvent and provides favorable conditions for subsequent mixing with a silica gel carrier; the silica gel particle size is 200 mesh to 400 mesh and has a larger specific surface area, which provides more sites for the attachment of aluminum phosphate, thereby improving the adsorption capacity and efficiency of the modified adsorbent.

[0034] Among them, the high porosity, for example, not less than 50%, allows more space inside the modified adsorbent to accommodate the adsorbate, thereby increasing the adsorption capacity of the modified adsorbent; whether it is magnetic stirring or mechanical stirring, uniform mixing of the mixture can be achieved at an appropriate rotation speed to ensure sufficient contact between the modified adsorbent and the triaryl phosphate; the experiment of the present invention proves that 800~1200r / min helps to enhance the mass transfer process in the mixed system, so that the modified adsorbent can adsorb the target compound faster; the organic solvent is completely removed by evaporation, which can remove impurities and unreacted raw materials that may exist in the modified adsorbent, thereby improving the purity and adsorption performance of the modified adsorbent.

[0035] The organic solvent used in the method of the present invention can be recycled, thereby reducing environmental pollution; meanwhile, the modified adsorbent can be reused or regenerated, thereby reducing production costs.

[0036] The method of the present invention is illustrated below with reference to specific embodiments.

[0037] Example 1

[0038] Take 5.0g of aluminum phosphate and dissolve it in 100ml of methanol, mix and stir, then add 15.0g of β zeolite to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove methanol to obtain about 20.0g of β zeolite modified adsorbent loaded with aluminum phosphate. Add 20.0g of modified adsorbent with a porosity of 50% to 500.0g of triaryl phosphate, mix and stir for 4h at 40°C, and filter and remove the modified adsorbent to obtain the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, magnetic stirring is used for mixing and stirring, and the speed is 800r / min.

[0039] Example 2

[0040] Take 5.0g of aluminum phosphate and dissolve it in 150ml of ethanol, mix and stir, then add 25.0g of 400 mesh silica gel to the mixed solution and mix it thoroughly. Then, use an evaporator to remove the ethanol to obtain about 30.0g of silica gel modified adsorbent loaded with aluminum phosphate. 30.0g of modified adsorbent with a porosity of 51% is added to 600.0g of triaryl phosphate, mixed and stirred at 40°C for 4h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, magnetic stirring is used for mixing and stirring, and the speed is 850r / min.

[0041] Example 3

[0042] Take 5.0g of aluminum phosphate and dissolve it in 200ml of propanol, mix and stir, then add 30.0g of diatomaceous earth to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 35.0g of diatomaceous earth modified adsorbent loaded with aluminum phosphate. 35.0g of modified adsorbent with a porosity of 52% is added to 875.0g of triaryl phosphate, mixed and stirred at 40°C for 4h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, magnetic stirring is used for mixing and stirring, and the speed is 900r / min.

[0043] Example 4

[0044] Take 5.0g of aluminum phosphate and dissolve it in 50ml of methanol, mix and stir, then add 20.0g of β zeolite to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove methanol to obtain about 25.0g of β zeolite modified adsorbent loaded with aluminum phosphate. 25.0g of modified adsorbent with a porosity of 55% is added to 625.0g of triaryl phosphate, mixed and stirred at 40°C for 4h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, magnetic stirring is used for mixing and stirring, and the speed is 950r / min.

[0045] Example 5

[0046] Take 5.0g of aluminum phosphate and dissolve it in 250ml of methanol, mix and stir, then add 25.0g of β zeolite to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove methanol to obtain about 30.0g of β zeolite modified adsorbent loaded with aluminum phosphate. 30.0g of modified adsorbent with a porosity of 57% is added to 500.0g of triaryl phosphate, mixed and stirred at 40°C for 4h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, magnetic stirring is used for mixing and stirring, and the speed is 1000r / min.

[0047] Example 6

[0048] Take 5.0g of aluminum phosphate and dissolve it in 50ml of ethanol, mix and stir, then add 30.0g of β zeolite to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove ethanol to obtain about 35.0g of β zeolite modified adsorbent loaded with aluminum phosphate. 35.0g of modified adsorbent with a porosity of 58% is added to 500.0g of triaryl phosphate, mixed and stirred at 40°C for 4h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts magnetic stirring, and the speed is 1050r / min.

[0049] Example 7

[0050] Take 5.0g of aluminum phosphate and dissolve it in 250ml of ethanol, mix and stir, then add 15.0g of β zeolite to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove ethanol to obtain about 20.0g of β zeolite modified adsorbent loaded with aluminum phosphate. Add 20.0g of modified adsorbent with a porosity of 60% to 500.0g of triaryl phosphate, mix and stir for 4h at 40°C, and filter and remove the modified adsorbent to obtain the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, magnetic stirring is used for mixing and stirring, and the speed is 1100r / min.

[0051] Example 8

[0052] Take 5.0g of aluminum phosphate and dissolve it in 50ml of propanol, mix and stir, then add 20.0g of β zeolite to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 25.0g of β zeolite modified adsorbent loaded with aluminum phosphate. 25.0g of modified adsorbent with a porosity of 62% is added to 500.0g of triaryl phosphate, mixed and stirred at 45°C for 3h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, magnetic stirring is used for mixing and stirring, and the speed is 1150r / min.

[0053] Example 9

[0054] Take 5.0g of aluminum phosphate and dissolve it in 250ml of propanol, mix and stir, then add 25.0g of β zeolite to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 30.0g of β zeolite modified adsorbent loaded with aluminum phosphate. 30.0g of modified adsorbent with a porosity of 64% is added to 500.0g of triaryl phosphate, mixed and stirred at 45°C for 3h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, magnetic stirring is used for mixing and stirring, and the speed is 1200r / min.

[0055] Example 10

[0056] Take 5.0g of aluminum phosphate and dissolve it in 210ml of propanol, mix and stir, then add 30.0g of β zeolite to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 35.0g of β zeolite modified adsorbent loaded with aluminum phosphate. 35.0g of modified adsorbent with a porosity of 66% is added to 500.0g of triaryl phosphate, mixed and stirred at 50°C for 2h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 800r / min.

[0057] Embodiment 11

[0058] Take 5.0g of aluminum phosphate and dissolve it in 230ml of ethanol, mix and stir, then add 15.0g of 300 mesh silica gel to the mixed solution and mix it thoroughly. Then, use an evaporator to remove the ethanol to obtain about 20.0g of silica gel modified adsorbent loaded with aluminum phosphate. Add 20.0g of modified adsorbent with a porosity of 68% to 500.0g of triaryl phosphate, mix and stir at 50°C for 2h, and filter and remove the modified adsorbent to obtain the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 850r / min.

[0059] Example 12

[0060] Take 5.0g of aluminum phosphate and dissolve it in 60ml of propanol, mix and stir, then add 20.0g of 300 mesh silica gel to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 25.0g of silica gel modified adsorbent loaded with aluminum phosphate. 25.0g of modified adsorbent with a porosity of 70% is added to 440.0g of triaryl phosphate, mixed and stirred at 50°C for 2h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 900r / min.

[0061] Embodiment 13

[0062] Take 5.0g of aluminum phosphate and dissolve it in 80ml of propanol, mix and stir, then add 25.0g of 200 mesh silica gel to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 30.0g of silica gel modified adsorbent loaded with aluminum phosphate. 30.0g of modified adsorbent with a porosity of 72% is added to 580.0g of triaryl phosphate, mixed and stirred at 55°C for 1h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 950r / min.

[0063] Embodiment 14

[0064] Take 5.0g of aluminum phosphate and dissolve it in 100ml of propanol, mix and stir, then add 30.0g of 200 mesh silica gel to the mixed solution and mix it thoroughly. Then, use an evaporator to remove the propanol to obtain about 35.0g of silica gel modified adsorbent loaded with aluminum phosphate. 35.0g of modified adsorbent with a porosity of 74% is added to 550.0g of triaryl phosphate, mixed and stirred at 55°C for 1h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 1000r / min.

[0065] Embodiment 15

[0066] Take 5.0g of aluminum phosphate and dissolve it in 120ml of ethanol, mix and stir, then add 15.0g of 400 mesh silica gel to the mixed solution and mix it thoroughly. Then, use an evaporator to remove the ethanol to obtain about 20.0g of silica gel modified adsorbent loaded with aluminum phosphate. Add 20.0g of modified adsorbent with a porosity of 76% to 400.0g of triaryl phosphate, mix and stir at 45°C for 2h, and filter and remove the modified adsorbent to obtain the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 1050r / min.

[0067] Example 16

[0068] Take 5.0g of aluminum phosphate and dissolve it in 140ml of propanol, mix and stir, then add 20.0g of 400 mesh silica gel to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 25.0g of silica gel modified adsorbent loaded with aluminum phosphate. 25.0g of modified adsorbent with a porosity of 78% is added to 460.0g of triaryl phosphate, mixed and stirred at 50°C for 3h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 1100r / min.

[0069] Embodiment 17

[0070] Take 5.0g of aluminum phosphate and dissolve it in 160ml of propanol, mix and stir, then add 25.0g of 400 mesh silica gel to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 30.0g of silica gel modified adsorbent loaded with aluminum phosphate. 30.0g of modified adsorbent with a porosity of 80% is added to 510.0g of triaryl phosphate, mixed and stirred at 60°C for 1h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 1150r / min.

[0071] Embodiment 18

[0072] Take 5.0g of aluminum phosphate and dissolve it in 180ml of propanol, mix and stir, then add 30.0g of 400 mesh silica gel to the mixed solution and mix it thoroughly. Then, use an evaporator to remove the propanol to obtain about 35.0g of silica gel modified adsorbent loaded with aluminum phosphate. 35.0g of modified adsorbent with a porosity of 82% is added to 520.0g of triaryl phosphate, mixed and stirred at 60°C for 1h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 1200r / min.

[0073] Embodiment 19

[0074] Take 5.0g of aluminum phosphate and dissolve it in 200ml of propanol, mix and stir, then add 15.0g of diatomaceous earth to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 20.0g of diatomaceous earth modified adsorbent loaded with aluminum phosphate. 20.0g of modified adsorbent with a porosity of 84% is added to 480.0g of triaryl phosphate, mixed and stirred at 60°C for 1h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 1200r / min.

[0075] Embodiment 20

[0076] Take 5.0g of aluminum phosphate and dissolve it in 220ml of propanol, mix and stir, then add 20.0g of diatomaceous earth to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 25.0g of diatomaceous earth modified adsorbent loaded with aluminum phosphate. 25.0g of modified adsorbent with a porosity of 86% is added to 490.0g of triaryl phosphate, mixed and stirred at 40°C for 3h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 1200r / min.

[0077] Embodiment 21

[0078] Take 5.0g of aluminum phosphate and dissolve it in 240ml of propanol, mix and stir, then add 25.0g of diatomaceous earth to the mixed solution and mix it thoroughly. Subsequently, use an evaporator to remove the propanol to obtain about 30.0g of diatomaceous earth modified adsorbent loaded with aluminum phosphate. 30.0g of modified adsorbent with a porosity of 88% is added to 375.0g of triaryl phosphate, mixed and stirred at 40°C for 2h, and the modified adsorbent is filtered to remove the treated triaryl phosphate. The titration method specified in GB 31604.46-2023 standard is used to determine the content of phenolic compounds in phosphate before and after adsorption; the EN14832 standard method is used to detect the oxidation stability of triaryl phosphate before and after adsorption; wherein, the mixing and stirring adopts mechanical stirring, and the speed is 1200r / min.

[0079] Among them, GB 31604.46-2023 is the "National Food Safety Standard - Determination of Free Phenol and Migration Amount in Food Contact Materials and Products"; EN14832 is "Petroleum and Related Products. Determination of Oxidative Stability and Corrosion of Refractory Phosphate Ester Liquids".

[0080] In Examples 1 to 21, the content of triaryl phosphate phenolic compounds before adsorption was 3549.1 ppm, the oxidative stability acid value was 0.45 mg KOH / g, the mass change of the iron sheet was +0.4 mg, and the mass change of the steel sheet was +0.6 mg. The content of triaryl phosphate phenolic compounds and the oxidative stability test results after adsorption are shown in Tables 1, 2 and 3:

[0081] Table 1 Test results of triaryl phosphate phenol content and oxidation stability after adsorption in Examples 1-7

[0082]

[0083] Table 2 Test results of triaryl phosphate phenol content and oxidation stability after adsorption in Examples 8-14

[0084]

[0085] Table 3 Test results of triaryl phosphate phenol content and oxidation stability after adsorption of Examples 15-21

[0086]

[0087] It can be seen from Table 1, Table 2 and Table 3 that the final test results of Examples 1 to 21 provided by the present invention show that after adsorption by the aluminum phosphate modified adsorbent, the content of phenolic compounds in the triaryl phosphate is significantly reduced, all below 960 ppm, and the oxidation stability indicators are significantly improved, all lower than the original values.

[0088] 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 effectively removing phenolic compounds from triaryl phosphates, characterized in that: The specific steps include: Aluminum phosphate is dissolved in an organic solvent, mixed and stirred, and then a carrier with a porous structure is added, and the organic solvent is removed after mixing to obtain a modified adsorbent; The modified adsorbent and the triaryl phosphate are mixed and stirred at 40-60° C., so that the modified adsorbent adsorbs the phenolic compounds in the triaryl phosphate, and after sufficient adsorption, the modified adsorbent is removed by filtering to obtain the triaryl phosphate after the phenolic compounds are removed; The solid-liquid ratio of the aluminum phosphate and the organic solvent is 1 g: (10-50) mL; the mass ratio of the aluminum phosphate and the carrier with a porous structure is 1: (3-6); The carrier with a porous structure is beta zeolite, silica gel or diatomaceous earth; The porosity of the modified adsorbent is not less than 50%.

2. A method for effectively removing phenolic compounds in triaryl phosphate according to claim 1, characterized in that: The particle size of the silica gel is 200-400 mesh.

3. A method for effectively removing phenolic compounds from triaryl phosphates according to claim 1, characterized in that: The mass of the modified adsorbent is 4% to 8% of the mass of the triaryl phosphate.

4. A method for effectively removing phenolic compounds from triaryl phosphates according to claim 1, characterized in that: The organic solvent is methanol, ethanol or propanol.

5. A method for effectively removing phenolic compounds from triaryl phosphates according to claim 1, characterized in that: The modified adsorbent and the triaryl phosphate are mixed and stirred for 1 to 4 hours.

6. A method for effectively removing phenolic compounds from triaryl phosphates according to claim 1, characterized in that: The mixing and stirring adopts magnetic stirring or mechanical stirring.

7. A method for effectively removing phenolic compounds from triaryl phosphates according to claim 1, characterized in that: The rotating speed of the mixing and stirring is 800-1200 r / min.

8. A method for effectively removing phenolic compounds from triaryl phosphates according to claim 1, characterized in that: After mixing, the organic solvent was removed by evaporation.

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