Working solution for synthesis of hydrogen peroxide by anthraquinone method

Abstract

This invention discloses a working solution for synthesizing hydrogen peroxide via the anthraquinone method, comprising a solvent and a working carrier. The solvent comprises aromatic hydrocarbons, diisobutylmethanol, and terephthalamide derivative A. Terephthalamide derivative A, by volume, has C9~C64... 10 The aromatic hydrocarbon comprises 30-95 parts, preferably 60-80 parts; the diisobutylmethanol comprises 2-20 parts, preferably 5-15 parts; and the terephthalamide derivative A comprises 5-30 parts, preferably 5-15 parts; the aromatic hydrocarbon is generally C9-C6. 10 Aromatic hydrocarbons; the working carrier is one or more of anthraquinone and its derivatives. This working solution exhibits excellent solubility and mass transfer capabilities for hydrogen, anthraquinone, and hydroanthraquinone, with a hydrogenation efficiency exceeding 13 g / L. It has low miscibility with water, good extraction and separation effects, and stable physicochemical properties. It can improve the production efficiency of the anthraquinone process for producing hydrogen peroxide and has promising prospects for industrial application.

Description

Technical Field

[0001] This invention pertains to the anthraquinone method for hydrogen peroxide preparation, specifically relating to a working solution for the anthraquinone method of hydrogen peroxide synthesis. Background Technology

[0002] Currently, over 99% of hydrogen peroxide products worldwide are produced using the anthraquinone process. This process uses 2-alkylanthraquinone as the working fluid carrier, circulating and alternating the anthraquinone working fluid through catalytic hydrogenation and auto-oxidation reactions. After extraction, purification, and concentration, hydrogen peroxide products of varying concentrations can be obtained. The working fluid, as the "lifeblood" of the anthraquinone process, has a decisive impact on the production efficiency of each production unit. Provided the physicochemical properties of the working fluid fully meet industrial requirements, industry generally uses the mass of H2O2 produced per unit volume of working fluid in a single pass (i.e., the number of grams of H2O2 produced per liter of working fluid) as a key indicator for evaluating production capacity.

[0003] Due to the significant differences in molecular polarity between anthraquinone and its hydrogenation products, a single solvent is insufficient to fully meet the requirements of the working solution. Therefore, the working solution solvent system is generally a mixture of a non-polar anthraquinone solvent and a polar hydrogen anthraquinone solvent. Currently, the working solution solvent system has low solubility for anthraquinone and hydrogen anthraquinone, resulting in low anthraquinone conversion rate and low hydrogenation efficiency. This further leads to a large working solution circulation volume in the unit and limited operational flexibility. The high density and viscosity of the working solution result in poor extraction and separation effects, severely limiting the quality of hydrogen peroxide products. Consequently, the quality grade of hydrogen peroxide is low, anthraquinone consumption is high, and the demand for high-purity hydrogen peroxide products cannot be met.

[0004] CN1552618A discloses a ternary working solution of aromatic hydrocarbon + trioctyl phosphate + methylcyclohexyl acetate (AR / TOP / MCHA). Compared with the traditional AR / TOP working solution, the AR / TOP / MCHA system can increase the solubility of 2-ethylanthraquinone by 30 g / L, and the hydrogenation efficiency of the working solution can be increased to 9-9.5 g / L. CN1583546A discloses a ternary working solution of aromatic hydrocarbon + trioctyl phosphate + tetrabutylurea (AR / TOP / TBU), which increases the solubility of hydrogen anthraquinone by nearly 10% compared with the AR / TOP working solution, and the hydrogenation efficiency of the working solution is slightly improved. CN101798065A discloses a ternary working solution of aromatic hydrocarbon + trioctyl phosphate + N-phenyl-N-ethylbenzamide, which increases the solubility of hydrogen anthraquinone by nearly 10-20% compared with the AR / TOP working solution, and the hydrogenation efficiency can reach 11-12 g / L. EP0287421 discloses an aromatic hydrocarbon + N-phenyl-N-ethylbenzamide (AR / BEA) binary working solution. While this system significantly improves the solubility of anthraquinone and hydroanthraquinone, the working solution formed with anthraquinone has a high density and high water solubility, resulting in poor hydrogen peroxide extraction and separation efficiency, and high carbon residue in the hydrogen peroxide product, leading to unsatisfactory application results. US4803063 discloses an aromatic hydrocarbon + N-phenyl-N-ethylbenzamide binary working solution. This solvent system has good solubility for both 2-alkylanthraquinone and 2-alkylhydroanthraquinone, achieving good hydrogenation efficiency and good oxidation stability. However, the solvent system exhibits long separation and demulsification times with water, severely affecting the separation efficiency of the extraction tower. In severe cases, water entrainment in the working solution affects the hydrogenation efficiency of the catalyst in the hydrogenation process, resulting in poor application results and failing to meet the application requirements of the hydrogen peroxide industry. CN111071993A discloses a working solution solvent molecule with the following diamide structure. The solvent system composed of this solvent and aromatic hydrocarbons also has good solubility for both 2-alkylanthraquinone and 2-alkylhydroanthraquinone, achieving good hydrogenation efficiency. The solvent system has a short separation and demulsification time with water, which can well meet the requirements of industrial use. However, the solvent degradation loss needs to be improved. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention proposes a working solution for the anthraquinone method of hydrogen peroxide synthesis. This working solution exhibits excellent solubility and mass transfer capabilities for hydrogen, anthraquinone, and hydrogen anthraquinone, with a hydrogenation efficiency exceeding 13 g / L. It also demonstrates low miscibility with water, good extraction and separation effects, and stable physicochemical properties. This solution can improve the production efficiency of the anthraquinone method for producing hydrogen peroxide and has promising prospects for industrial application.

[0006] The working solution for synthesizing hydrogen peroxide via the anthraquinone method of the present invention includes a solvent and a working carrier, wherein the solvent includes an aromatic hydrocarbon, diisobutylmethanol, and terephthalamide derivative A, and the structural formula of terephthalamide derivative A is:

[0007] R1, R2, R3, and R4 are alkane substituents, furan, benzyl, or aromatic substituents with 1 to 8 carbon atoms, respectively, and the alkane substituents, furan, benzyl, or aromatic substituents may also contain one or more functional groups selected from alkyl, alkoxy, and ester groups; by volume, C9 to C 10 The aromatic hydrocarbon is 30-95 parts, preferably 60-80 parts; the diisobutylmethanol is 2-20 parts, preferably 5-15 parts; and the terephthalamide derivative A is 5-30 parts, preferably 5-15 parts.

[0008] In the working fluid of this invention, the aromatic hydrocarbon is generally C9-C6. 10 Aromatic hydrocarbons; R1 to R4 in terephthalamide derivative A are preferably C1 to C6 normal / isomeric alkyl substituents. The number of carbon atoms in substituents at different positions can be adjusted according to the different physicochemical properties required by the working solution. The total number of carbon atoms in R1 to R4 is generally not higher than 20.

[0009] In the working fluid of the present invention, the working carrier is one or more of anthraquinone and its derivatives, preferably 2-alkylanthraquinone, and more preferably 2-ethylanthraquinone, 2-butylanthraquinone, or 2-pentylanthraquinone.

[0010] This invention also provides a hydrogenation process for producing hydrogen peroxide using the anthraquinone process, wherein the working fluid described above is used in the hydrogenation process; the reactor in the hydrogenation process can be a fluidized bed, slurry bed, or fixed bed, and the hydrogenation process conditions are: hydrogenation temperature 25–80°C, pressure 0.1–0.7 MPa. The hydrogenation process can use hydrogenation catalysts well-known in the field of anthraquinone process technology, wherein the hydrogenation active component is generally Pd, the support is generally alumina or silica gel, and auxiliary components such as one or more of Mo, Na, K, Ni, Mg, Au, Ca, and Fe can also be added to the catalyst. Based on the weight of the hydrogenation catalyst components, the content of the hydrogenation active component is 0.05%–5%, and the content of the auxiliary components is 0.05%–3%.

[0011] The preparation method of terephthalic acid derivative A of the present invention includes the following steps: (1) dissolving terephthalic acid in organic solvent A, and carrying out a dehydration reaction under the action of acyl chloride C, wherein the functional group of terephthalic acid is replaced by chlorine atoms to generate terephthalic acid dicarboxylic acid chloride D, and separating the acyl chloride after the reaction is completed, and further separating the terephthalic acid dicarboxylic acid chloride D by vacuum distillation; (2) dissolving terephthalic acid dicarboxylic acid chloride D in organic solvent B, adding an appropriate amount of dialkylamine and triethylamine mixture, and carrying out an amidation reaction under certain temperature conditions to obtain crude terephthalic acid derivative A, and separating and purifying to obtain terephthalic acid derivative A.

[0012] In the method of this invention, the dehydration reaction formula in step (1) is as follows (taking phosphoric acid acyl chloride PCl5 as an example):

[0013]

[0014] In the method of the present invention, the organic solvent A in step (1) is selected from one or more of chlorobenzene, dichloromethane, trichloromethane, N,N-dimethylacetamide or ethyl acetate, and the molar ratio of organic solvent A to terephthalic acid is 1:1.5 to 75, preferably 2 to 30.

[0015] In the method of the present invention, the acyl chloride C in step (1) is one or more of phosphoric acid acyl chloride, phosphorous acid acyl chloride or sulfite acyl chloride, and the molar ratio of acyl chloride C to terephthalic acid is 1:1 to 20, preferably 2 to 8.

[0016] In the method of this invention, the dehydration reaction conditions in step (1) are: atmospheric pressure, 100-120℃ for 2-4 hours. After the reaction is completed, the organic solvent A, acyl chloride C and the intermediate product p-phenylenedicarboxylic acid acyl chloride D are separated by vacuum distillation according to their different boiling points.

[0017] In the method of the present invention, the dialkylamine mentioned in step (2) is dialkylamine D1 (NHR1R2) and dialkylamine D1 (NHR3R4), wherein R1, R2, R3 and R4 are one of furan, aromatic substituent, benzyl or alkane substituent, and the furan, aromatic substituent, benzyl or alkane substituent may also contain one or more functional groups of alkyl, alkoxy and ester groups.

[0018] In the method of the present invention, the reaction formula in step (2) is as follows:

[0019]

[0020] In the method of the present invention, the organic solvent B in step (2) is selected from chlorobenzene, dichloromethane or trichloromethane, and the molar ratio of organic solvent B to terephthalic acid acyl chloride D is 1:1.5 to 100, preferably 2 to 30.

[0021] In the method of the present invention, the molar ratio of dialkylamines D1 and D2 to terephthalic acid acyl chloride D in step (2) is 1:1:0.5-1. Terephthalic acid acyl chloride D can be mixed with dialkylamine and triethylamine at once, or added dropwise to the mixture.

[0022] In the method of the present invention, the reaction conditions in step (2) are 50-120°C and normal pressure, and the reaction solution is reacted in a reflux reactor for 0.5-4 hours to obtain a crude product mixture containing terephthalamide derivative A.

[0023] In the method of this invention, the separation and extraction process is as follows: After the crude product mixture containing terephthalamide derivative A is cooled to room temperature, a small amount of insoluble matter generated during the reaction is filtered out. The reaction solution is washed with hydrochloric acid, sodium carbonate solution, and deionized water until neutral. The lower organic phase is separated by standing, and then purified by vacuum distillation to finally obtain the target product, terephthalamide derivative A. The washing generally involves washing the reaction mixture 2-4 times with hydrochloric acid, sodium carbonate solution, and deionized water until the final reaction solution is neutral.

[0024] Compared with the prior art, the working solution of the present invention has the following advantages: (1) Good solubility for anthraquinone: Under the anthraquinone process conditions, the solubility of the working solution for 2-alkyl anthraquinone can be increased by more than 35% compared with the existing industrial working solution. Under the anthraquinone process conditions, the solubility of 2-alkyl anthraquinone can reach more than 90 g / L, which can significantly increase the effective anthraquinone concentration in the working solution and improve the hydrogenation conversion rate of anthraquinone; (2) High solubility for anthraquinone: Under room temperature conditions, the solubility of the composite solvent for 2-ethyl anthraquinone reaches more than 180 g / L, which can be increased by 2% compared with the existing industrial working solution. (2) High hydrogenation efficiency: Under the above hydrogenation catalyst and hydrogenation conditions, the hydrogenation efficiency of 2-ethylanthraquinone working solution can reach more than 11.5 g / L, and the hydrogenation efficiency of 2-pentylanthraquinone working solution can reach more than 15 g / L; (3) High hydrogenation efficiency: Under the above hydrogenation catalyst and hydrogenation conditions, the hydrogenation efficiency of 2-ethylanthraquinone working solution can reach more than 11.5 g / L, and the hydrogenation efficiency of 2-pentylanthraquinone working solution can reach more than 15 g / L; (4) Stable physical and chemical properties of working solution, low density and viscosity, high hydrogenation efficiency, and low miscibility with water; (5) Good antioxidant properties of working solution, low solvent decomposition rate, and low residual carbon in hydrogen peroxide product, which can greatly improve the production capacity and utilization efficiency of anthraquinone hydrogen peroxide plant. Detailed Implementation

[0025] The present invention will be further described below with reference to specific preferred embodiments, but this does not limit the scope of protection of the present invention. The performance evaluation method for the working fluid is as follows:

[0026] (1) Evaluation method of hydrogenation test: The anthraquinone working solution was subjected to catalytic hydrogenation reaction in a 500ml mechanically stirred reactor at a hydrogenation temperature of 55℃, a hydrogenation pressure of 0.3MPa, and a stirring rate of 400rpm. The resulting hydrogenated solution was oxidized with air at atmospheric pressure and 50℃ for 1 hour. The oxidized solution was extracted four times using a separatory funnel, and the concentration of hydrogen peroxide in the extract was determined by potassium permanganate titration. The hydrogenation efficiency was calculated. The catalyst used in the hydrogenation test was a conventional Pd / Al2O3 catalyst with a particle size of 0.4-0.5mm and a pore volume of 0.6-0.7cm. 3 / g, specific surface area 150~180m² 2 / g, with a Pd content of 0.25wt% to 0.35wt%.

[0027] (2) Hydrogenation efficiency analysis method: After the working solution undergoes catalytic hydrogenation reaction, 5 ml of hydrogenated solution is promptly taken into a separatory funnel using a precision pipette. The hydrogenated solution is diluted with 50 ml of heavy aromatic hydrocarbons, 100 ml of ultrapure water, and 15 ml of 22.5% dilute sulfuric acid solution. High-purity air is introduced into the separatory funnel, and the hydrogenated solution is fully oxidized under normal temperature and pressure conditions. After the 2-ethylanthraquinone working solution is fully oxidized for 15 min and the 2-pentylanthraquinone working solution is fully oxidized for 25 min, the oxidized solution is extracted with ultrapure water. After three parallel extractions, the concentration of hydrogen peroxide in the extract is titrated using the potassium permanganate titration method. Before titration, the potassium permanganate solution needs to be prepared and its concentration calibrated. Accurately weigh 3.4g of potassium permanganate crystals, dissolve them in 1000ml of ultrapure water, place them in a brown bottle and let them stand for 5-7 days. After filtering the supernatant through a sintered glass funnel, the concentration of the supernatant is determined by sodium oxalate (Na2C2O4). Accurately weigh 0.20g of Na2C2O4, dry it at 110℃ for 2 hours, dissolve it in 30ml of ultrapure water and 25ml of 22.5% dilute sulfuric acid solution, heat the mixture to 85℃, and titrate the potassium permanganate solution while it is hot. When the titrant remains pink for 30s without fading, it is considered the titration endpoint. Record the amount of potassium permanganate consumed, and calculate the concentration of the potassium permanganate solution (C) using equations (1) and (2), respectively. KmnO4 ) and the hydrogenation efficiency (η) of the working fluid:

[0028]

[0029]

[0030] (3) Method for determining the solubility of 2-alkylanthraquinone: Place a 500ml three-necked flask in a constant temperature water bath, and control the water bath temperature to be constant at 25℃±0.1℃; 10 Aromatic hydrocarbons, diisobutylmethanol, and terephthalamide derivative A were prepared into 200 ml test solvents and added to a three-necked flask at different volume fractions. Under constant temperature conditions, the anthraquinone to be tested was gradually dissolved at a rate of 5 mg / min until the anthraquinone no longer dissolved. The total amount of anthraquinone dissolved was recorded, and the solubility of anthraquinone in different solvent systems was calculated.

[0031] (4) Method for determining the solubility of 2-alkylanthraquinone: Different working solutions containing 2-ethylanthraquinone or 2-pentylanthraquinone were subjected to hydrogenation reaction in a transparent and visible fixed-bed reaction tube. The reaction temperature was 55℃ and the reaction pressure was 0.1~0.3MPa. The flow state of the working solution was monitored. When the working solution reached a turbid state (critical precipitation state), the hydrogenation reaction was stopped. The composition of the working solution at this time was analyzed by high performance liquid chromatography, and the hydrogenation efficiency of anthraquinone was determined at the same time. Under the condition that no obvious degradation products were detected by high performance liquid chromatography, the solubility of 2-alkylanthraquinone in the solvent system was calculated based on the hydrogenation efficiency value.

[0032] (5) Analysis method for extraction partition coefficient of working solution: The liquid-liquid equilibrium analysis method was carried out according to GB / T 1616-2014. A ternary system (working solution-pure water-hydrogen peroxide) of a certain concentration was thoroughly mixed in a 250ml constant temperature volumetric flask with a glass jacket. After standing for 2.5 hours under constant temperature conditions, the inorganic aqueous phase and the organic working solution phase were separated. The hydrogen peroxide content in the former was directly determined by potassium permanganate titration, and the organic working solution content was analyzed by a TOC residual carbon analyzer. The latter was extracted with pure water three times at the same temperature, and the hydrogen peroxide content was analyzed by the same method. The pure water content was analyzed by a Karl Fischer moisture analyzer. After three parallel experiments, the mass concentration ratio of hydrogen peroxide in the aqueous phase and the organic phase of the working solution was taken as the extraction partition coefficient.

[0033] (6) Analysis method of antioxidant properties of working solution: Air is introduced into a 500ml mechanically stirred reactor to carry out oxidation reaction of working solution. The oxidation temperature is 150-200℃, the oxidation pressure is 0.1-0.15MPa, and the stirring rate is 400rpm. After 150h of oxidation reaction, the components of working solution are qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry, and the decomposition rate of terephthalamide derivative A before and after oxidation reaction is calculated.

[0034] (7) Working fluid density and viscosity analysis methods:

[0035] The density and viscosity of different working fluids were analyzed and determined according to the standards SH / T 0604-2000 and GB 265-1988, respectively.

[0036] Example 1

[0037] Taking the synthesis process of N,N,N',N'-tetrabutylterephthalamide as an example:

[0038]

[0039] In a 500 mL reactor, 116 g of 1,4-phenylenediacetic acid, 150 mL of dichloromethane, and 250 g of PCl5 were added in a single batch. The system temperature was raised to 100 °C, and the reactants were thoroughly dissolved under vigorous stirring. After maintaining the system temperature for 2 hours, the reaction was stopped, and the system was allowed to cool naturally to 40–50 °C. The reactants were then transferred to a distillation vessel, and the reaction solution was subjected to vacuum distillation at this temperature. Further vacuum distillation was then carried out at -0.1 MPa and 75–78 °C to separate dichloromethane and PCl5. Finally, the system temperature was further increased to 128–132 °C to obtain the fraction in this temperature range as phenylenediacetyl chloride. In another 500 mL reactor, 258.5 g of dibutylamine and 15 g of PCl5 were added in a single batch. 0 ml of triethylamine was added to the reaction vessel, followed by phenylacetyl chloride. After thorough stirring until the reactants were uniformly mixed, the reaction was carried out under normal pressure, 100 °C, and reflux for 2 hours. After the reaction was completed, the reaction solution was washed four times with 22.5 wt.% hydrochloric acid, 30 wt.% sodium carbonate aqueous solution, and pure water to make the reaction solution neutral. The reaction solution was then transferred to a distillation vessel and subjected to vacuum distillation at -0.1 MPa to obtain the target product at 205–208 °C. The obtained product was confirmed by 1H NMR and MS spectral analysis to be N,N,N',N'-tetrabutylphthalamide, with a yield of 94.1%.

[0040] 1H NMR (500MHz, CDCl3) δ=0.92~0.97(m, 12H), 1.30~1.38(m, 8H), 1.47~1.54(m, 8H), 3.18~3.24(m, 8H), 3.58~3.62(m, 4H), 7.20~7.23(m, 4H); MS[M+H] + :412.1.

[0041] Example 2

[0042] Taking the synthesis process of N,N,N',N'-tetraethylterephthalamide as an example:

[0043]

[0044] In a 500 mL reactor, 58 g of 1,4-phenylenediacetic acid, 100 mL of dichloromethane, and 125 g of PCl5 were added in a single batch. The system temperature was raised to 100 °C, and the reactants were fully dissolved under thorough stirring. After maintaining the system temperature for 2 hours, the reaction was stopped, and the system was allowed to cool naturally to 40–50 °C. The reactants were then transferred to a distillation vessel, and the reaction solution was subjected to vacuum distillation at this temperature. Further vacuum distillation was then carried out at -0.1 MPa and 75–78 °C to separate dichloromethane and PCl5. Finally, the system temperature was further increased to 128–132 °C to obtain the fraction in this temperature range as phenylenediacetyl chloride. In another 500 mL reactor, 130 g of diethylamine and 100 mL of PCl5 were added in a single batch. 1 ml of triethylamine was added to the reaction vessel, followed by a single addition of phenylacetyl chloride. The mixture was stirred thoroughly until homogeneous, and then reacted at atmospheric pressure, 100°C, and reflux for 2 hours. After the reaction, the resulting reaction solution was washed four times with 22.5 wt.% hydrochloric acid, 30 wt.% sodium carbonate aqueous solution, and pure water to ensure neutrality. The reaction solution was then transferred to a distillation vessel and subjected to vacuum distillation at -0.1 MPa to obtain the target product at 205–208°C. The product was confirmed by 1H NMR and MS spectral analysis to be N,N,N',N'-tetraethylphenylenediamide, with a yield of 95.7%.

[0045] 1H NMR (500MHz, CDCl3) δ=0.92~0.97(m, 12H), 1.33~1.38(m, 8H), 1.41~1.49(m, 8H), 3.21~3.26(m, 8H), 3.58~3.62(m, 4H), 7.20~7.23(m, 4H); MS[M+H] + :301.4.

[0046] Example 3

[0047] A ternary composite agent system for working fluid in the anthraquinone hydrogen peroxide production process, comprising C9 to C14 compounds. 10 Aromatic hydrocarbons, diisobutylmethanol, and N,N,N',N'-tetraethylterephthalamide were prepared by the method of Example 1. The composite working solution uses 2-ethylanthraquinone as the anthraquinone carrier, and the ternary solvent, by volume, comprises C9-C9 components. 10Aromatic hydrocarbons: diisobutylmethanol: N,N,N',N'-tetraethylterephthalamide = 75:20:5 were used to prepare a 2-ethylanthraquinone working solution. Experimental results showed that at 25℃, the solubility of 2-ethylanthraquinone in this composite solvent system was 169.5 g / L; at 50–55℃ and 0.25–0.28 MPa, the solubility of 2-ethylhydroanthraquinone was 91.6 g / L; the hydrogenation efficiency of the working solution with a 2-ethylanthraquinone mass concentration of 165 g / L was 11.5 g / L; the oxidative decomposition rate of the composite working solution was 7.6%; and the working solution density was 0.921 g / cm³. 3 The viscosity is 0.235 Pa·s, the organic residual carbon in the hydrogen peroxide product is 95.1 ppm, and the separation and demulsification time of the working solution and pure water is 37 s.

[0048] Example 4

[0049] A ternary composite agent system for working fluid in the anthraquinone hydrogen peroxide production process, comprising C9 to C14 compounds. 10 Aromatic hydrocarbons, diisobutylmethanol, and N,N,N',N'-tetraethylterephthalamide were prepared by the method of Example 1. The composite working solution uses 2-pentylanthraquinone as the anthraquinone carrier, and the ternary solvent, by volume, comprises C9-C9... 10 Aromatic hydrocarbons: diisobutylmethanol: N,N,N',N'-tetraethylterephthalamide = 75:15:10 were used to prepare a 2-pentylanthraquinone working solution. Experimental results showed that at 25℃, the solubility of 2-pentylanthraquinone in this working solution solvent system was 564.9 g / L; at 50–55℃ and 0.25–0.28 MPa, the solubility of 2-pentylhydroanthraquinone was 129.2 g / L; the hydrogenation efficiency of the working solution with a 2-pentylanthraquinone mass concentration of 300 g / L was 18.4 g / L; the oxidative decomposition rate of the composite working solution was 14.5%; and the working solution density was 0.937 g / cm³. 3 The viscosity was 0.273 Pa·s, the organic residual carbon in the hydrogen peroxide product was 115.3 ppm, and the separation and demulsification time between the working solution and pure water was 36 s.

[0050] Example 5

[0051] A ternary composite agent system for working fluid in the anthraquinone hydrogen peroxide production process, comprising C9 to C14 compounds. 10 Aromatic hydrocarbons, diisobutylmethanol, and N,N'-methoxy-N,N'-dipropylterephthalamide. The composite working solution uses 2-ethylanthraquinone as the anthraquinone carrier, and the ternary solvent, by volume, comprises C9–C64 compounds. 10Aromatic hydrocarbons: diisobutylmethanol: N,N'-methoxy-N,N'-dipropylterephthalic acid amide = 75:5:20 were used to prepare a 2-ethylanthraquinone working solution. Experimental results showed that at 25℃, the solubility of 2-ethylanthraquinone in this working solution solvent system was 185.7 g / L; at 50–55℃ and 0.25–0.28 MPa, the solubility of 2-ethylhydroanthraquinone was 97.6 g / L; the hydrogenation efficiency of the working solution with a 2-ethylanthraquinone mass concentration of 180 g / L was 13.1 g / L; the oxidative decomposition rate of the composite working solution was 16.8%; and the working solution density was 0.928 g / cm³. 3 The viscosity was 0.233 Pa·s, the organic residual carbon in the hydrogen peroxide product was 109.5 ppm, and the separation and demulsification time between the working solution and pure water was 33 s.

[0052] Example 6

[0053] A ternary composite agent system for working fluid in the anthraquinone hydrogen peroxide production process, comprising C9 to C14 compounds. 10 Aromatic hydrocarbons, diisobutylmethanol, and N,N'-benzyl-N,N'-diethylterephthalamide. The composite working solution uses 2-pentylanthraquinone as the anthraquinone carrier, and the ternary solvent, by volume, comprises C9–C64 compounds. 10 Aromatic hydrocarbons: diisobutylmethanol: N,N'-benzyl-N,N'-diethylterephthalamide = 60:20:20 were used to prepare a 2-pentylanthraquinone working solution. Experimental results showed that at 25℃, the solubility of 2-pentylanthraquinone in this working solution solvent system was 532.7 g / L; at 55–60℃ and 0.25–0.30 MPa, the solubility of 2-pentylhydroanthraquinone was 158.6 g / L; the hydrogenation efficiency of the working solution with a 2-pentylanthraquinone mass concentration of 300 g / L was 18.8 g / L; the oxidative decomposition rate of the composite working solution was 20.2%; and the working solution density was 0.939 g / cm³. 3 The viscosity is 0.244 Pa·s, and the organic residual carbon in the hydrogen peroxide product is 161.6 ppm.

[0054] Example 7

[0055] A ternary composite agent system for working fluid in the anthraquinone hydrogen peroxide production process, comprising C9 to C14 compounds. 10 Aromatic hydrocarbons, diisobutylmethanol, and N,N,N',N'-tetrabutylterephthalamide. The composite working solution uses 2-ethylanthraquinone as the anthraquinone carrier, and the ternary solvent, by volume, comprises C9–C64 compounds. 10A 2-ethylanthraquinone working solution was prepared by mixing aromatic hydrocarbons, diisobutylmethanol, and N,N,N',N'-tetrabutylterephthalamide in a ratio of 75:12.5:12.5. Experimental results showed that the solubility of 2-ethylanthraquinone in this working solution solvent system was 180.3 g / L at 25℃, and 92.5 g / L at 50–55℃ and 0.25–0.28 MPa. The hydrogenation efficiency of the working solution with a 2-ethylanthraquinone mass concentration of 180 g / L was 13.4 g / L, the oxidative decomposition rate of the composite working solution was 11.5%, and the working solution density was 0.927 g / cm³. 3 The viscosity is 0.231 Pa·s, and the organic residual carbon in the hydrogen peroxide product is 117.2 ppm.

[0056] Comparative Example 1

[0057] Measured by volume fraction, in C9~C 10 A mixture of aromatic hydrocarbons and trioctyl phosphate (75 / 25) was used as the solvent, and 2-ethylanthraquinone was used as the anthraquinone carrier to prepare the working solution. The performance of this working solution system was analyzed using the method described above. Experimental results showed that 2-ethylanthraquinone, under 25℃ and normal pressure conditions, exhibits good performance at C9–C9. 10 The solubility of 2-ethylanthraquinone in the aromatic hydrocarbon / trioctyl phosphate working solution system is 123–130 g / L. Under conditions of 50–55 °C and 0.25–0.30 MPa, the solubility of 2-ethylanthraquinone is 68.5–69 g / L. The hydrogenation efficiency of the working solution with a 2-ethylanthraquinone mass concentration of 125 g / L is 6.5–7.3 g / L. The solubility of H2 in this working solution system is 1.12 mmol / L. The degradation rate of the working solution is 29.8%, and the density of the working solution is 0.929 g / cm³. 3 The viscosity is 0.237 Pa·s, the organic residual carbon in the hydrogen peroxide product is 355 ppm, and the separation and demulsification time between the working solution and pure water is 31 s.

[0058] Comparative Example 2

[0059] The working solution was prepared according to Example 3 of CN1552618A, and its performance was analyzed as described above. The experimental results showed that, under conditions of 53–60℃ and 0.25–0.30 MPa, the working solution with a 2-ethylanthraquinone concentration of 154 g / L exhibited a solubility of 51.5–53.1 g / L for hydroanthraquinone, a hydrogenation efficiency of 7.4–7.8 g / L, a H2 solubility of 1.27 mmol / L, a degradation rate of 33.1%, and a working solution density of 0.935 g / cm³. 3 The viscosity is 0.254 Pa·s, the organic residual carbon in the hydrogen peroxide product is 851 ppm, and the separation and demulsification time between the working solution and pure water is 33 s.

[0060] Comparative Example 3

[0061] A 2-ethylanthraquinone working solution was prepared according to the binary solvent system of aromatic hydrocarbon + N-phenyl-N-ethylbenzamide (BEA) disclosed in EP0287421. The performance of this working solution system was analyzed as described above. Experimental results showed that the solubility of 2-ethylanthraquinone in this working solution system was 155–163 g / L at 25℃ and atmospheric pressure, and 85–89 g / L at 55–60℃ and 0.25–0.30 MPa. The hydrogenation efficiency of the working solution with a 2-ethylanthraquinone mass concentration of 150 g / L was 10.33 g / L, the degradation rate was 22.6%, and the density was 0.933 g / cm³. 3 The viscosity is 0.241 Pa·s, the organic residual carbon in the hydrogen peroxide product is 1031 ppm, the solvent oxidation decomposition rate is 12.9%, and the separation and demulsification time between the working solution and pure water is 72 s.

[0062] Comparative Example 4

[0063] A 2-ethylanthraquinone working solution was prepared according to the binary solvent system of aromatic hydrocarbon + N,N-dibutyl-N',N'-diethylbutanediamide disclosed in CN111071993A. The performance of this working solution system was analyzed using the method described above. Experimental results showed that the solubility of 2-ethylanthraquinone in the working solution system was 165 g / L at 25℃ and normal pressure; the solubility of 2-ethylhydroanthraquinone was 94.5 g / L at 55–60℃ and 0.25–0.30 MPa; the hydrogenation efficiency of the working solution with a 2-ethylanthraquinone mass concentration of 150 g / L was 10.33 g / L; the organic residual carbon in the hydrogen peroxide product was 129.6 ppm; the oxidative decomposition rate of the solvent during 120 hours of oxidation was 17.3%; and the separation and demulsification time between the working solution and pure water was 41 s.

[0064] Comparative Example 5

[0065] A 2-ethylanthraquinone working solution was prepared according to the binary solvent system of aromatic hydrocarbon + N-phenyl-N-ethylbenzamide disclosed in US4803063, and its performance was analyzed as described above. The experimental results showed that the solubility of 2-ethylanthraquinone in the working solution system was 158.5 g / L at 25℃ and normal pressure, and 83.1 g / L at 55–60℃ and 0.25–0.30 MPa. The hydrogenation efficiency of the working solution with a 2-ethylanthraquinone mass concentration of 150 g / L was 10.33 g / L. The organic residual carbon in the hydrogen peroxide product was 133.4 ppm. The oxidative decomposition rate of the solvent during 120 hours of oxidation was 12.1%, and the separation and demulsification time between the working solution and pure water was 63 s.

Claims

1. A working solution for synthesizing hydrogen peroxide via the anthraquinone method, characterized in that: The system includes a solvent and a working carrier, wherein the solvent comprises an aromatic hydrocarbon, diisobutylmethanol, and terephthalamide derivative A, the structural formula of which is: R1, R2, R3, and R4 are alkane substituents, furan, benzyl, or aromatic substituents with 1 to 8 carbon atoms, respectively, and are C9 to C4 substituents by volume. 10 The aromatic hydrocarbons are 30-95 parts, the diisobutylmethanol is 2-20 parts, and the terephthalamide derivative A is 5-30 parts.

2. The working fluid according to claim 1, characterized in that: The alkane substituent, furan, benzyl or aromatic substituent further contains one or more functional groups selected from alkyl, alkoxy, and ester groups.

3. The working fluid according to claim 1, characterized in that: In terephthalamide derivative A, R1 to R4 are C1 to C6 normal / isomeric alkyl substituents, and the total number of carbon atoms in R1 to R4 is not higher than 20.

4. The working fluid according to claim 1, characterized in that: The working carrier is one or more of anthraquinone and its derivatives.

5. The working fluid according to claim 1, characterized in that: The working carrier is 2-alkylanthraquinone.

6. The working fluid according to claim 1, characterized in that: The preparation method of terephthalic acid derivative A includes the following: (1) dissolving terephthalic acid in organic solvent A, and carrying out a dehydration reaction under the action of acyl chloride C, the functional group of terephthalic acid is replaced by chlorine atoms to generate terephthalic acid dicarboxylic acid chloride D, and separating the acyl chloride after the reaction is completed, and further separating the terephthalic acid dicarboxylic acid chloride D by vacuum distillation; (2) dissolving terephthalic acid dicarboxylic acid chloride D in organic solvent B, adding an appropriate amount of dialkylamine and triethylamine mixture, and carrying out an amidation reaction under certain reaction conditions to obtain crude terephthalic acid derivative A, and separating and purifying to obtain terephthalic acid derivative A.

7. The working fluid according to claim 6, characterized in that: In the preparation method of the terephthalic acid derivative A, the organic solvent A in step (1) is selected from one or more of chlorobenzene, dichloromethane, trichloromethane, N,N-diethylformamide or ethyl acetate, and the molar ratio of organic solvent A to terephthalic acid is 1:1.5~75.

8. The working fluid according to claim 6, characterized in that: In the preparation method of the terephthalamide derivative A, the acyl chloride C in step (1) is one or more of phosphoric acid acyl chloride, phosphorous acid acyl chloride or sulfite acyl chloride, and the molar ratio of acyl chloride C to terephthalic acid is 1:1~20.

9. The working fluid according to claim 6, characterized in that: In the preparation method of the terephthalamide derivative A, the dehydration reaction conditions in step (1) are: atmospheric pressure, 100~120℃ for 2~4 hours.

10. The working fluid according to claim 6, characterized in that: In the preparation method of the terephthalamide derivative A, the dialkylamine in step (2) is dialkylamine D1 NHR1R2 and dialkylamine D2 NHR3R4, wherein R1, R2, R3 and R4 are one of furan, aromatic substituent, benzyl or alkane substituent, respectively.

11. The working fluid according to claim 6, characterized in that: In the preparation method of the terephthalamide derivative A, the organic solvent B in step (2) is selected from chlorobenzene, dichloromethane or trichloromethane, and the molar ratio of organic solvent B to terephthalic acid acyl chloride D is 1:1.5~100.

12. The working fluid according to claim 6, characterized in that: In the preparation method of the terephthalamide derivative A, the molar ratio of the dialkylamines D1 and D2 to the terephthalic acid acyl chloride D in step (2) is 1:1:0.5~1.

13. The working fluid according to claim 6, characterized in that: In the preparation method of the terephthalamide derivative A, the amidation reaction in step (2) is carried out at 50~120℃ and normal pressure, and the reaction solution is reacted in a reflux reactor for 0.5~4 hours to obtain a crude product mixture of terephthalamide derivative A.

14. The working fluid according to claim 6, characterized in that: In the preparation method of the terephthalamide derivative A, the separation and purification process in step (2) is as follows: after the crude product mixture containing terephthalamide derivative A is cooled to room temperature, the small amount of insoluble matter generated during the reaction is filtered out, and the reaction solution is washed with hydrochloric acid, sodium carbonate solution and deionized water until neutral. The lower organic phase is separated by standing, and then the terephthalamide derivative A is obtained by vacuum distillation. The washing is performed by washing the reaction mixture with hydrochloric acid, sodium carbonate solution and deionized water until neutral.

15. The application of the working solution for the anthraquinone method for synthesizing hydrogen peroxide according to any one of claims 1 to 6 in the hydrogen peroxide preparation process.

16. A hydrogenation process for producing hydrogen peroxide using the anthraquinone method, characterized in that: The hydrogenation process uses the working fluid described in any one of claims 1 to 6.

17. The hydrogenation process according to claim 16, characterized in that: The reactor can be a fluidized bed, slurry bed, or fixed bed. The hydrogenation process conditions are: hydrogenation temperature 25–80℃, pressure 0.1–0.7 MPa. The active component of the hydrogenation catalyst is Pd, the support is alumina or silica gel, and the promoter component in the hydrogenation catalyst is one or more of the elements Mo, Na, K, Ni, Mg, Au, Ca, and Fe. The content of the active component and the promoter is 0.05%–5% by weight of the hydrogenation catalyst.

Images