Heteropolyacid catalyst as well as preparation method and application thereof

Abstract

The invention discloses a heteropolyacid quaternary ammonium salt catalyst, a preparation method thereof and application of the heteropolyacid quaternary ammonium salt catalyst in synthesis of bis (tert-butylperoxy isopropyl) benzene (BIPB), and belongs to the technical field of catalysts. The structure of the heteropolyacid quaternary ammonium salt catalyst is as follows: QaHbXMcYdZeO40, wherein Q is a quaternary ammonium salt cation, M is a central metal atom, X is a heteroatom, and Y and Z are substituted metal atoms. Bimetal atoms replace part of central metal atoms to form trimetal active sites with a synergistic effect, meanwhile, quaternary ammonium salt with a hydrophobic function and a phase transfer function is introduced, and heteropoly acid is synergistically modified by bimetal substitution and quaternary ammonium salt, so that the hydrophobicity and stability of the catalyst are improved; therefore, the catalyst has high catalytic activity and selectivity. When the heteropolyacid quaternary ammonium salt catalyst is applied to synthesis of BIPB, the reaction condition is mild, the reaction time is shortened, side reactions are reduced, the yield and purity of BIPB are improved, the process safety is high, and the production cost is reduced; corrosion to equipment is reduced, and the catalyst is easily separated from a product and is convenient to recycle; the process is simplified, alkali washing and water washing links of the condensation liquid are reduced, discharge of a large amount of wastewater is reduced, and green production of synthesized BIPB can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of catalysts, and in particular relates to a heteropolyacid quaternary ammonium salt catalyst and a preparation method thereof, and application of the heteropolyacid quaternary ammonium salt catalyst in synthesizing bis(tert-butylperoxyisopropyl)benzene (BIPB). Background Art

[0002] Bis(tert-butylperoxyisopropyl)benzene, abbreviated as BIPB, commonly known as "odorless DCP", is a dialkyl organic peroxide crosslinking agent second only to DCP in usage. It is widely used as a crosslinking agent in plastics and a vulcanizing agent in rubber. With the increasingly stringent environmental protection regulations, the domestic market demand for BIPB is also increasing.

[0003] According to patent literature, there are four main methods for synthesizing BIPB, but the condensation reaction synthesis method is usually used as the production method of BIPB in industry, that is, under the action of an acidic catalyst, di-(2-hydroxy-2-propyl)benzene (DC for short) and tert-butyl hydroperoxide (TBHP for short) undergo condensation dehydration reaction to generate BIPB. The currently reported condensation synthesis technology for BIPB usually uses sulfuric acid as a catalyst. The disadvantages of this preparation method are: ① a large amount of waste sulfuric acid is generated, which can neither be recycled nor treated and discharged, which is not conducive to environmental protection; ② the presence of sulfuric acid easily causes the decomposition of tert-butyl hydroperoxide, resulting in a low reaction yield; ③ a large amount of sulfuric acid seriously corrodes the equipment; ④ the safety of this production process is relatively low.

[0004] Patent CN106588735B discloses a method for producing bis(tert-butyl peroxyisopropyl)benzene, which uses di-(2-hydroxyisopropyl)benzene and tert-butyl hydroperoxide aqueous solution as raw materials, perchloric acid aqueous solution as catalyst, and toluene as solvent, and performs condensation dehydration reaction under negative pressure to prepare BIPB. This preparation method reduces raw material loss and speeds up the reaction process, but the disadvantages are that toluene has a high boiling point, poor water separation effect, and difficulty in removing the solvent in the later stage. The use of liquid catalysts such as sulfuric acid and perchloric acid cannot overcome the disadvantages of liquid catalysts such as easy corrosion of equipment, difficulty in separation, and inability to recycle.

[0005] Patent CN101544587A discloses a method for preparing α,α′-bis(tert-butylperoxy)diisopropylbenzene. The preparation method uses phosphotungstic acid containing crystal water as a catalyst, tert-butyl hydroperoxide hydrate and α,α′-dihydroxy-p-diisopropylbenzene as raw materials, and reacts in an organic solvent for 15-25 hours to prepare α,α′-bis(tert-butylperoxy)diisopropylbenzene. The disadvantages of the preparation method are: ① phosphotungstic acid has strong hygroscopicity, which is inconvenient to store and use; ② phosphotungstic acid is expensive, the amount used is large, and the raw material cost is high; ③ the reaction time is long and the reaction efficiency is low; ④ the reaction conversion rate and selectivity are low; ⑤ phosphotungstic acid also has problems such as small specific surface area and poor thermal stability. Summary of the invention

[0006] The technical problems to be solved by the present invention are the problems caused by the use of traditional liquid catalysts in the prior art, such as easy corrosion of equipment, difficulty in separation, inability to recycle, and generation of a large amount of wastewater, as well as the problems of strong hygroscopicity, long reaction time, low reaction efficiency, low reaction conversion rate and selectivity in the use of heteropolyacid catalysts in the prior art.

[0007] In order to achieve the above object, the present invention first provides a heteropolyacid quaternary ammonium salt catalyst, the structure of the heteropolyacid quaternary ammonium salt catalyst is as follows: a H b XM c Y d Z e O 40 , where Q is a quaternary ammonium cation, represented by [R1R2R3R4N] + It represents that N is a nitrogen atom, R1, R2, R3, and R4 are selected from hydrogen atoms, linear or branched alkyl groups, and benzyl groups, and R1, R2, R3, and R4 are the same or different; M is a central metal atom, which is selected from at least one element of Mo and W; X is a heteroatom, which is selected from one or more elements of P, Si, As, and Ge; Y is a substituted metal atom, which is selected from one or more elements of Cr, V, Mn, Fe, and Zr; Z is a substituted metal atom, which is selected from one or more elements of Ni, Co, Cu, Zn, and Cd; wherein a=1-3, b=0-2, c=0.1-10, d=1-6, and e=1-6.

[0008] Considering the source of raw materials and cost control, X is preferably one or more elements selected from P and Si; considering the synergistic effect between the substituting metal atom and the central metal atom, Y is preferably one or more elements selected from V and Cr; and Z is preferably one or more elements selected from Ni and Co.

[0009] In order to ensure the active effect produced by the combination of the substituted metal atom and the central metal atom, c is preferably 6-10, d is preferably 2-5, and e is preferably 1-4.

[0010] Secondly, the present invention provides a method for preparing a heteropolyacid quaternary ammonium salt, comprising the following steps:

[0011] 1) According to the chemical formula QaHbXMcYdZeO40, a compound containing the elements required for each active component is dissolved in deionized water, mixed evenly, and the pH of the feed solution is adjusted to 1-5 to obtain a mixed solution A containing heteropolyacid.

[0012] 2) Dissolve the quaternary ammonium salt in deionized water until it is completely dissolved to obtain solution B.

[0013] 3) Slowly drop solution B into mixed solution A at 20-50° C. with stirring. After the dropwise addition, continue the reaction for 0.5-3 h. Filter the resulting precipitate, wash with deionized water, and vacuum dry at 45-55° C. to obtain the heteropolyacid quaternary ammonium salt catalyst.

[0014] Furthermore, the compound containing the element required for the active component in step 1) is one or more of the corresponding oxides, hydroxides, nitrates, chlorides, acetates and carbonates.

[0015] Furthermore, in step 1), the pH of the feed solution is adjusted to 1-5 with nitric acid. To ensure the full extent of the reaction, the pH is preferably 2-4.

[0016] Further, the quaternary ammonium salt described in step 2) is selected from one or more of octadecyl trimethyl ammonium chloride, octadecyl trimethyl ammonium bromide, hexadecyl trimethyl ammonium chloride, hexadecyl trimethyl ammonium bromide, tetradecyl trimethyl ammonium chloride, and tetradecyl trimethyl ammonium bromide. Considering the source of raw materials and the fact that the long chain can better improve the hydrophobicity of heteropolyacids, one or more of octadecyl trimethyl ammonium chloride and hexadecyl trimethyl ammonium chloride is preferred.

[0017] Furthermore, in order to save materials and reduce the generation of wastewater, the amount of water added in step 2) is sufficient to completely dissolve the quaternary ammonium salt.

[0018] Furthermore, in order to ensure the substitution effect on the heteropoly acid, the molar ratio of the heteropoly acid in step 1) to the molar ratio of the quaternary ammonium salt in step 2) is 1:(1-4).

[0019] Furthermore, in order to control energy consumption and ensure sufficient reaction, the reaction temperature and reaction time are optimized: under the conditions of 20-50°C and stirring, preferably 30-40°C; continue the reaction for 0.5-3h, preferably 1-2h.

[0020] Again, the present invention provides an application of a heteropolyacid quaternary ammonium salt catalyst in the synthesis of BIPB, using di-(2-hydroxyisopropyl)benzene and tert-butyl hydroperoxide aqueous solution as raw materials, using the heteropolyacid quaternary ammonium salt as a catalyst, and carrying out a condensation reaction in an organic solvent, comprising the following steps:

[0021] 1) Adding tert-butyl hydroperoxide aqueous solution and dehydrating agent into a condensation reaction kettle, stirring and mixing evenly, standing to separate layers, and draining the bottom aqueous phase, thus completing the dehydration treatment of the tert-butyl hydroperoxide aqueous solution.

[0022] 2) Add di-(2-hydroxyisopropyl)benzene, an organic solvent and a quaternary ammonium salt catalyst of a heteropolyacid into a condensation reaction kettle, turn on the hot water in the jacket of the condensation reaction kettle to increase the temperature, turn on the vacuum pump to evacuate the kettle, and at the same time, bubbling nitrogen, stirring and decompressing the kettle under reflux to complete the condensation dehydration reaction.

[0023] 3) When the condensation reaction is finished, add alkali solution with a mass concentration of 3-5% to terminate the reaction.

[0024] 4) After the reaction is terminated, the condensation liquid is filtered, and the filtrate is distilled under reduced pressure to remove the solvent to obtain the product. The filter cake obtained by filtration is the heteropolyacid quaternary ammonium salt catalyst, which can be recycled.

[0025] Furthermore, the dehydrating agent in step 1) is selected from one or more of sodium sulfate and sodium carbonate, and the weight ratio of the dehydrating agent to the aqueous solution of tert-butyl hydroperoxide is 0.01-0.05:1. In order to ensure the dehydrating effect of the dehydrating agent on the aqueous solution of tert-butyl hydroperoxide and save raw materials, it is preferably 0.02-0.04:1.

[0026] Furthermore, the organic solvent in step 2) is selected from one or more of cyclohexane and n-hexane, and the weight ratio of the organic solvent to di-(2-hydroxyisopropyl)benzene is 1.5-4.5:1. In order to ensure the dispersion effect and water-carrying effect of the organic solvent on the reaction system and reduce the generation of organic waste liquid, it is preferably 2-3:1.

[0027] Furthermore, the molar ratio of di-(2-hydroxyisopropyl)benzene to tert-butyl hydroperoxide added in step 2) is 1:2.1-2.7, preferably 1:2.2-2.5 to ensure the completeness of the reaction and reduce material waste; the weight ratio of di-(2-hydroxyisopropyl)benzene to the heteropolyacid quaternary ammonium salt catalyst is 1:0.05%-0.40%, preferably 1:0.10%-0.35% to ensure sufficient catalytic effect and stable and controllable reaction.

[0028] Furthermore, in order to ensure that the reaction proceeds sufficiently and smoothly, avoid excessive reaction, and ensure a high conversion rate, the reaction temperature, vacuum degree and reaction time are optimized respectively. The condensation reaction temperature is 35 to 60°C, preferably 40 to 55°C; the vacuum degree is -0.02 to -0.08MPa, preferably -0.03 to -0.07MPa; the reaction time is 1 to 5h, preferably 2 to 4.5h.

[0029] The beneficial effects of the present invention are:

[0030] 1. The heteropolyacid quaternary ammonium salt catalyst of the present invention, which replaces part of the central metal atoms with dimetallic atoms to form a trimetallic active site with a synergistic effect, introduces a quaternary ammonium salt with a hydrophobic function and a phase transfer function, and the dimetallic substitution and the quaternary ammonium salt synergistically modify the heteropolyacid, improve the hydrophobicity and stability of the catalyst, and make the catalyst have higher catalytic activity and selectivity.

[0031] 2. The heteropolyacid quaternary ammonium salt catalyst of the present invention is insoluble in the reaction system itself, but is dissolved in the reaction system very quickly after reacting with tert-butyl hydroperoxide, and catalyzes the condensation reaction homogeneously; after the tert-butyl hydroperoxide is consumed, the heteropolyacid quaternary ammonium salt catalyst can be precipitated out from the reaction system and can be recycled by filtering and recovery.

[0032] 3. The heteropolyacid quaternary ammonium salt catalyst of the present invention is applied to the synthesis of BIPB, and the reaction conditions are mild, the reaction time is shortened, the side reactions are reduced, the reaction conversion rate and selectivity are improved, the yield and purity of BIPB are improved, the process safety is high, and the production cost is reduced.

[0033] 4. The heteropolyacid quaternary ammonium salt catalyst of the present invention is easy to separate and recycle; it reduces corrosion to equipment, simplifies the process, reduces the alkali washing and water washing steps of the condensation liquid, reduces the discharge of a large amount of waste water, and can realize the green production of synthetic BIPB. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention are clearly and completely described in the following preferred implementation modes, so as to make a clearer and more definite definition of the protection scope of the present invention.

[0035] 1. Preparation Example of Heteropolyacid Quaternary Ammonium Salt Catalyst

[0036] Example 1

[0037] (a) 43.2 g of molybdenum trioxide, 35 g of nickel nitrate, and 9.1 g of vanadium pentoxide were dissolved in 240 g of deionized water, and 6 g of 85% phosphoric acid was added and mixed evenly. The pH of the feed solution was adjusted to 3.0 with nitric acid to obtain a mixed solution A.

[0038] (b) 34.8 g of octadecyltrimethylammonium chloride was dissolved in 200 g of deionized water until it was completely dissolved to obtain a solution B.

[0039] (c) Solution B was slowly added dropwise to the mixed solution A at 35° C. with stirring. After the addition was complete, the reaction was continued for 1.5 h. The resulting precipitate was filtered, washed with deionized water, and dried under vacuum at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 18 H 37 )N(CH3)3]2HPMo6V2Ni4O 40 , i.e. catalyst 1.

[0040] Example 2

[0041] (a) 53 g Na2WO4·2H2O, 3.7 g vanadium pentoxide, and 7 g cobalt nitrate were dissolved in 260 g deionized water, and 2.4 g 85% phosphoric acid was added and mixed evenly. The pH of the feed solution was adjusted to 3.5 with nitric acid to obtain a mixed solution A.

[0042] (b) 25.6 g of hexadecyltrimethylammonium chloride was dissolved in 180 g of deionized water until it was completely dissolved, thereby obtaining a solution B.

[0043] (c) Solution B was slowly added dropwise to the mixed solution A at 30° C. with stirring. After the addition was complete, the reaction was continued for 2 h. The resulting precipitate was filtered, washed with deionized water, and dried under vacuum at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 16 H 33 )N(CH3)3]3PW8V2Co2O 40 , i.e. catalyst 2.

[0044] Example 3

[0045] (a) 50.4 g of molybdenum trioxide, 27 g of nickel nitrate, 9.1 g of vanadium pentoxide and 12.1 g of sodium silicate were dissolved in 300 g of deionized water and mixed well. The pH of the feed solution was adjusted to 2.0 with nitric acid to obtain a mixed solution A.

[0046] (b) 17.4 g of octadecyltrimethylammonium chloride was dissolved in 160 g of deionized water until it was completely dissolved, thereby obtaining a solution B.

[0047] (c) Solution B was slowly added dropwise to the mixed solution A at 35° C. with stirring. After the addition was complete, the reaction was continued for 1.5 h. The resulting precipitate was filtered, washed with deionized water, and dried under vacuum at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 18 H 37 )N(CH3)3]H2SiMo7V2Ni3O40 , namely catalyst 3.

[0048] Example 4

[0049] (a) 40 g Na2WO4·2H2O, 9.1 g vanadium pentoxide, 3.5 g cobalt nitrate and 5 g sodium silicate were dissolved in 300 g deionized water and mixed evenly. The pH of the feed solution was adjusted to 4.0 with nitric acid to obtain a mixed solution A.

[0050] (b) 16 g of hexadecyltrimethylammonium chloride was dissolved in 150 g of deionized water until it was completely dissolved to obtain a solution B.

[0051] (c) Solution B was slowly added dropwise to the mixed solution A at 40° C. with stirring. After the addition was complete, the reaction was continued for 1 hour. The resulting precipitate was filtered, washed with deionized water, and dried in vacuo at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 16 H 33 )N(CH3)3]2HSiW6V5CoO 40 , namely catalyst 4.

[0052] Example 5

[0053] (a) 34.6 g of molybdenum trioxide, 7 g of nickel nitrate, and 15.2 g of chromium trioxide were dissolved in 280 g of deionized water, and 4 g of 85% phosphoric acid was added and mixed well. The pH of the feed solution was adjusted to 2.5 with nitric acid to obtain a mixed solution A.

[0054] (b) 55.7 g of octadecyltrimethylammonium chloride was dissolved in 300 g of deionized water until it was completely dissolved to obtain a solution B.

[0055] (c) Solution B was slowly added dropwise to the mixed solution A at 30° C. with stirring. After the addition was complete, the reaction was continued for 2 h. The resulting precipitate was filtered, washed with deionized water, and dried under vacuum at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 18 H 37 )N(CH3)3]3PMo6Cr5NiO 40 , namely catalyst 5.

[0056] Example 6

[0057] (a) 66 g Na2WO4·2H2O, 3.04 g chromium trioxide, 3.5 g cobalt nitrate and 5 g sodium silicate were dissolved in 400 g deionized water and mixed well. The pH of the feed solution was adjusted to 3.0 with nitric acid to obtain a mixed solution A.

[0058] (b) 6.4 g of hexadecyltrimethylammonium chloride was dissolved in 100 g of deionized water until it was completely dissolved to obtain solution B.

[0059] (c) Solution B was slowly added dropwise to the mixed solution A at 40° C. with stirring. After the addition was complete, the reaction was continued for 1 hour. The resulting precipitate was filtered, washed with deionized water, and dried in vacuo at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 16 H 33 )N(CH3)3]H2SiW 10 CrCoO 40 , namely catalyst 6.

[0060] Example 7

[0061] (a) 38.9 g of molybdenum trioxide, 11.3 g of copper nitrate, and 2.7 g of manganese dioxide were dissolved in 260 g of deionized water, and 3 g of 85% phosphoric acid was added and mixed evenly. The pH of the feed solution was adjusted to 3.0 with nitric acid to obtain a mixed solution A.

[0062] (b) 19.2 g of hexadecyltrimethylammonium chloride was dissolved in 150 g of deionized water until it was completely dissolved, thereby obtaining a solution B.

[0063] (c) Solution B was slowly added dropwise to the mixed solution A at 30° C. with stirring. After the addition was complete, the reaction was continued for 2 h. The resulting precipitate was filtered, washed with deionized water, and dried under vacuum at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 16 H 33 )N(CH3)3]2HPMo9MnCu2O 40 , namely catalyst 7.

[0064] Example 8

[0065] (a) 53 g Na2WO4·2H2O, 4.8 g ferric oxide, and 2.8 g zinc chloride were dissolved in 300 g deionized water, and 2 g 85% phosphoric acid was added and mixed evenly. The pH of the feed solution was adjusted to 5.0 with nitric acid to obtain a mixed solution A.

[0066] (b) 7.2 g of octadecyltrimethylammonium chloride was dissolved in 100 g of deionized water until it was completely dissolved to obtain a solution B.

[0067] (c) Solution B was slowly added dropwise to the mixed solution A at 30° C. with stirring. After the addition was complete, the reaction was continued for 2 h. The resulting precipitate was filtered, washed with deionized water, and dried under vacuum at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 18 H 37 )N(CH3)3]H2PW8Fe3ZnO 40 , namely catalyst 8.

[0068] Example 9

[0069] (a) 7.2 g of molybdenum trioxide, 43.8 g of nickel nitrate, and 27.3 g of vanadium pentoxide were dissolved in 350 g of deionized water, and 6 g of 85% phosphoric acid was added and mixed evenly. The pH of the feed solution was adjusted to 3.0 with nitric acid to obtain a mixed solution A.

[0070] (b) 41.8 g of octadecyltrimethylammonium chloride was dissolved in 260 g of deionized water until it was completely dissolved, thereby obtaining a solution B.

[0071] (c) Solution B was slowly added dropwise to the mixed solution A at 30° C. with stirring. After the addition was complete, the reaction was continued for 2 h. The resulting precipitate was filtered, washed with deionized water, and dried under vacuum at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 18 H 37 )N(CH3)3]2HPMoV6Ni5O 40 , i.e. catalyst 9.

[0072] Example 10

[0073] (b) 33 g Na2WO4·2H2O, 1.9 g vanadium pentoxide, and 22 g cobalt nitrate were dissolved in 280 g deionized water, and 2.4 g 85% phosphoric acid was added and mixed evenly. The pH of the feed solution was adjusted to 3.5 with nitric acid to obtain a mixed solution A.

[0074] (b) 22.4 g of hexadecyltrimethylammonium chloride was dissolved in 200 g of deionized water until it was completely dissolved to obtain a solution B.

[0075] (c) Solution B is slowly added dropwise to the mixed solution A at 25° C. with stirring. After the addition is complete, the reaction is continued for 2 h. The resulting precipitate is filtered, washed with deionized water, and dried in vacuo at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 16 H 33 )N(CH3)3]3PW5VCo6O 40 , that is, catalyst 10.

[0076] Embodiment 11

[0077] (a) 40.4 g of molybdenum trioxide, 21 g of nickel nitrate, 7.3 g of vanadium pentoxide and 9.7 g of sodium silicate were dissolved in 300 g of deionized water and mixed well. The pH of the feed solution was adjusted to 2.0 with nitric acid to obtain a mixed solution A.

[0078] (b) 17.5 g of octadecyltrimethylammonium chloride was dissolved in 180 g of deionized water until it was completely dissolved, thereby obtaining a solution B.

[0079] (c) Solution B was slowly added dropwise to the mixed solution A at 35° C. with stirring. After the addition was complete, the reaction was continued for 1.5 h. The resulting precipitate was filtered, washed with deionized water, and dried under vacuum at 45 to 55° C. to obtain a heteropolyacid quaternary ammonium salt catalyst [(C 14 H 29 )N(CH3)3]H2SiMo7V2Ni3O 40 , that is, catalyst 11.

[0080] Comparative Example 1

[0081] (a) 7 g of octadecyltrimethylammonium chloride was completely dissolved in 100 g of deionized water, and 30 g of phosphotungstic acid was completely dissolved in 200 g of deionized water.

[0082] (b) Slowly drop the octadecyltrimethylammonium chloride solution into the phosphotungstic acid solution at 30°C with stirring. After the dropwise addition, the reaction was continued for 2 hours. The obtained precipitate was filtered, washed with deionized water, and vacuum dried at 45-55°C to obtain the heteropolyacid quaternary ammonium salt catalyst [(C 18 H 37 )N(CH3)3]2HPW 12 O 40 , i.e. comparative catalyst 1.

[0083] Comparative Example 2

[0084] (a) 10 g of hexadecyltrimethylammonium chloride was completely dissolved in 120 g of deionized water, and 30 g of silicotungstic acid was completely dissolved in 200 g of deionized water.

[0085] (b) Slowly add the hexadecyltrimethylammonium chloride solution to the phosphotungstic acid solution at 35°C with stirring. After the addition, continue the reaction for 1.5 hours, filter the resulting precipitate, wash it with deionized water, and dry it in a vacuum at 45-55°C to obtain the heteropolyacid quaternary ammonium salt catalyst [(C 16 H 33 )N(CH3)3]3SiW 12 O 40 , i.e. comparative catalyst 2.

[0086] Comparative Example 3

[0087] Heteropolyphosphotungstic acid H3PW 12 O 40 , i.e. comparative catalyst 3.

[0088] 2. An example of synthesizing BIPB using the heteropolyacid quaternary ammonium salt catalyst prepared by 1-11 of the present invention.

[0089] Application Example 1

[0090] (1) Adding tert-butyl hydroperoxide aqueous solution and sodium sulfate in a weight ratio of 1:0.03 into a condensation reaction kettle, stirring and mixing evenly, standing to separate layers, and draining the bottom aqueous phase, thus completing the dehydration treatment of the tert-butyl hydroperoxide aqueous solution.

[0091] (2) Add di-(2-hydroxyisopropyl)benzene, cyclohexane and catalyst 1 into the condensation reactor, the molar ratio of di-(2-hydroxyisopropyl)benzene to tert-butyl hydroperoxide is 1:2.4, and the weight ratio of di-(2-hydroxyisopropyl)benzene, cyclohexane and catalyst 1 is 1:2.5:0.20%. Turn on the hot water in the jacket of the condensation reactor to increase the temperature, turn on the vacuum pump to evacuate, the condensation reaction temperature is 45°C, the vacuum degree is -0.045MPa, nitrogen is bubbled at the same time, and the mixture is stirred and refluxed under reduced pressure for 3.9 hours to complete the condensation dehydration reaction.

[0092] (3) When the condensation reaction is finished, add alkali solution with a mass concentration of 3-5% to terminate the reaction.

[0093] (4) After the reaction is terminated, the condensation liquid is filtered, and the filtrate is distilled under reduced pressure to remove the solvent to obtain the product. The filter cake obtained by filtration is the catalyst 1, which can be recycled.

[0094] Application Example 2

[0095] (1) Adding tert-butyl hydroperoxide aqueous solution and sodium sulfate in a weight ratio of 1:0.04 into a condensation reaction kettle, stirring and mixing evenly, standing to separate layers, and draining the bottom aqueous phase, thus completing the dehydration treatment of the tert-butyl hydroperoxide aqueous solution.

[0096] (2) Add di-(2-hydroxyisopropyl)benzene, n-hexane and catalyst 2 into the condensation reactor, the molar ratio of di-(2-hydroxyisopropyl)benzene to tert-butyl hydroperoxide is 1:2.3, and the weight ratio of di-(2-hydroxyisopropyl)benzene, n-hexane and catalyst 2 is 1:2.5:0.30%. Turn on the hot water in the jacket of the condensation reactor to increase the temperature, turn on the vacuum pump to evacuate, the condensation reaction temperature is 55°C, the vacuum degree is -0.07MPa, nitrogen is bubbled at the same time, and the mixture is stirred and refluxed under reduced pressure for 2.1h to complete the condensation dehydration reaction.

[0097] (3) When the condensation reaction is finished, add alkali solution with a mass concentration of 3-5% to terminate the reaction.

[0098] (4) After the reaction is terminated, the condensation liquid is filtered, and the filtrate is distilled under reduced pressure to remove the solvent to obtain the product. The filter cake obtained by filtration is the catalyst 2, which can be recycled.

[0099] Application Example 3

[0100] (1) Adding tert-butyl hydroperoxide aqueous solution and sodium carbonate in a weight ratio of 1:0.03 into a condensation reaction kettle, stirring and mixing evenly, standing to separate layers, and draining the bottom aqueous phase, thus completing the dehydration treatment of the tert-butyl hydroperoxide aqueous solution.

[0101] (2) Add di-(2-hydroxyisopropyl)benzene, n-hexane and catalyst 3 into the condensation reactor, the molar ratio of di-(2-hydroxyisopropyl)benzene to tert-butyl hydroperoxide is 1:2.5, and the weight ratio of di-(2-hydroxyisopropyl)benzene, n-hexane and catalyst 3 is 1:3.0:0.10%. Turn on the hot water in the jacket of the condensation reactor to increase the temperature, turn on the vacuum pump to evacuate, the condensation reaction temperature is 45°C, the vacuum degree is -0.042MPa, nitrogen is bubbled at the same time, and the mixture is stirred and refluxed under reduced pressure for 4.5 hours to complete the condensation dehydration reaction.

[0102] (3) When the condensation reaction is finished, add alkali solution with a mass concentration of 3-5% to terminate the reaction.

[0103] (4) After the reaction is terminated, the condensation liquid is filtered, and the filtrate is distilled under reduced pressure to remove the solvent to obtain the product. The filter cake obtained by filtration is the catalyst 3, which can be recycled.

[0104] Application Example 4

[0105] (1) Adding tert-butyl hydroperoxide aqueous solution and sodium carbonate in a weight ratio of 1:0.02 into a condensation reaction kettle, stirring and mixing evenly, standing to separate layers, and draining the bottom aqueous phase, thus completing the dehydration treatment of the tert-butyl hydroperoxide aqueous solution.

[0106] (2) Add di-(2-hydroxyisopropyl)benzene, n-hexane and catalyst 4 into the condensation reactor, the molar ratio of di-(2-hydroxyisopropyl)benzene to tert-butyl hydroperoxide is 1:2.2, and the weight ratio of di-(2-hydroxyisopropyl)benzene, n-hexane and catalyst 4 is 1:2.0:0.35%. Turn on the hot water in the jacket of the condensation reactor to increase the temperature, turn on the vacuum pump to evacuate, the condensation reaction temperature is 45°C, the vacuum degree is -0.063MPa, nitrogen is bubbled at the same time, and the mixture is stirred and refluxed under reduced pressure for 2.6 hours to complete the condensation dehydration reaction.

[0107] (3) When the condensation reaction is finished, add alkali solution with a mass concentration of 3-5% to terminate the reaction.

[0108] (4) After the reaction is terminated, the condensation liquid is filtered, and the filtrate is distilled under reduced pressure to remove the solvent to obtain the product. The filter cake obtained by filtration is the catalyst 4, which can be recycled.

[0109] Application Example 5

[0110] (1) Adding tert-butyl hydroperoxide aqueous solution and sodium sulfate in a weight ratio of 1:0.02 into a condensation reaction kettle, stirring and mixing evenly, standing to separate layers, and draining the bottom aqueous phase, thus completing the dehydration treatment of the tert-butyl hydroperoxide aqueous solution.

[0111] (2) Add di-(2-hydroxyisopropyl)benzene, cyclohexane and catalyst 5 into the condensation reactor, the molar ratio of di-(2-hydroxyisopropyl)benzene to tert-butyl hydroperoxide is 1:2.4, and the weight ratio of di-(2-hydroxyisopropyl)benzene, cyclohexane and catalyst 5 is 1:2.0:0.25%. Turn on the hot water in the jacket of the condensation reactor to increase the temperature, turn on the vacuum pump to evacuate, the condensation reaction temperature is 50°C, the vacuum degree is -0.033MPa, nitrogen is bubbled at the same time, and the mixture is stirred and refluxed under reduced pressure for 3.5 hours to complete the condensation dehydration reaction.

[0112] (3) When the condensation reaction is finished, add alkali solution with a mass concentration of 3-5% to terminate the reaction.

[0113] (4) After the reaction is terminated, the condensation liquid is filtered, and the filtrate is distilled under reduced pressure to remove the solvent to obtain the product. The filter cake obtained by filtration is the catalyst 5, which can be recycled.

[0114] Application Example 6

[0115] (1) Adding tert-butyl hydroperoxide aqueous solution and sodium carbonate in a weight ratio of 1:0.04 into a condensation reaction kettle, stirring and mixing evenly, standing to separate layers, and draining the bottom aqueous phase, thus completing the dehydration treatment of the tert-butyl hydroperoxide aqueous solution.

[0116] (2) Add di-(2-hydroxyisopropyl)benzene, cyclohexane and catalyst 6 into the condensation reactor, the molar ratio of di-(2-hydroxyisopropyl)benzene to tert-butyl hydroperoxide is 1:2.2, and the weight ratio of di-(2-hydroxyisopropyl)benzene, cyclohexane and catalyst 6 is 1:3.0:0.15%. Turn on the hot water in the jacket of the condensation reactor to increase the temperature, turn on the vacuum pump to evacuate, the condensation reaction temperature is 40°C, the vacuum degree is -0.055MPa, nitrogen is bubbled at the same time, and the mixture is stirred and refluxed under reduced pressure for 4 hours to complete the condensation dehydration reaction.

[0117] (3) When the condensation reaction is finished, add alkali solution with a mass concentration of 3-5% to terminate the reaction.

[0118] (4) After the reaction is terminated, the condensation liquid is filtered, and the filtrate is distilled under reduced pressure to remove the solvent to obtain the product. The filter cake obtained by filtration is the catalyst 6, which can be recycled.

[0119] Application Example 7

[0120] The same process and reaction conditions as those in Application Example 1 were used, except that the catalyst was changed to Catalyst 7.

[0121] Application Example 8

[0122] The same process and reaction conditions as those in Application Example 2 were used, except that the catalyst was changed to Catalyst 8.

[0123] Application Example 9

[0124] The same process and reaction conditions as those in Application Example 3 were adopted, except that the catalyst was changed to Catalyst 9.

[0125] Application Example 10

[0126] The same process and reaction conditions as those in Application Example 4 were adopted, with only the catalyst being changed to catalyst 10.

[0127] Application Example 11

[0128] The same process and reaction conditions as those in Application Example 5 were adopted, except that the catalyst was changed to catalyst 11.

[0129] Application Example 12

[0130] The same process and reaction conditions as those in Application Example 1 were adopted, except that the weight ratio of the aqueous tert-butyl hydroperoxide solution to sodium sulfate was changed to 1:0.01.

[0131] Application Example 13

[0132] The same process and reaction conditions as those in Application Example 2 were used, except that the weight ratio of di-(2-hydroxyisopropyl)benzene to n-hexane was changed to 1:1.5.

[0133] Application Example 14

[0134] The same process and reaction conditions as those in Application Example 3 were used, except that the weight ratio of di-(2-hydroxyisopropyl)benzene to catalyst 4 was 1:0.05%.

[0135] Application Example 15

[0136] The same process and reaction conditions as those in Application Example 4 were used, except that the molar ratio of di-(2-hydroxyisopropyl)benzene to tert-butyl hydroperoxide was changed to 1:2.1.

[0137] Application Example 16

[0138] The same process and reaction conditions as those in Application Example 5 were adopted, except that the vacuum degree was changed to -0.02 MPa.

[0139] Application Example 17

[0140] The same process and reaction conditions as those in Application Example 6 were used, except that the condensation reaction temperature was changed to 35°C.

[0141] Comparative Application Example 1

[0142] The same process and reaction conditions as those in Application Example 1 were adopted, except that the catalyst was changed to Comparative Catalyst 1.

[0143] Comparative Application Example 2

[0144] The same process and reaction conditions as those in Application Example 3 were adopted, except that the catalyst was changed to Comparative Catalyst 2.

[0145] Comparative Application Example 3

[0146] The same process and reaction conditions as those in Application Example 5 were adopted, except that the catalyst was changed to Comparative Catalyst 3.

[0147] The yield and purity of the product BIPB obtained in each application example of the present invention and the comparative application example are shown in Table 1.

[0148] Table 1 Evaluation results of various embodiments and comparative examples

[0149] Appearance Yield / % purity / % Application Example 1 White solid 92.5 97.6 Application Example 2 White solid 91.7 98.1 Application Example 3 White solid 91.5 97.8 Application Example 4 White solid 92.8 97.5 Application Example 5 White solid 91.2 98.4 Application Example 6 White solid 92.1 97.9 Application Example 7 White solid 90.8 96.8 Application Example 8 White solid 89.9 96.3 Application Example 9 White solid 90.2 96.5 Application Example 10 White solid 89.7 96.1 Application Example 11 White solid 90.1 96.7 Application Example 12 White solid 91.2 96.5 Application Example 13 White solid 90.3 97.0 Application Example 14 White solid 89.6 96.8 Application Example 15 White solid 91.3 97.0 Application Example 16 White solid 89.5 97.1 Application Example 17 White solid 90.0 97.2 Comparative application example 1 White solid 84.5 95.4 Comparative Application Example 2 White solid 83.9 95.9 Comparative Application Example 3 White solid 68.5 93.8

[0150] It can be known from the combination of application examples 1 to 17 and comparative application examples 1 to 3 that, compared with the unmodified heteropolyacid catalyst or quaternary ammonium salt single modified heteropolyacid catalyst of the comparative example, the heteropolyacid quaternary ammonium salt catalyst of the present invention, by replacing part of the central metal atoms with dimetallic atoms to form a trimetallic active site with a synergistic effect, introduces a quaternary ammonium salt with a hydrophobic function and a phase transfer function, and the dimetallic substitution and quaternary ammonium salt synergistically modify the heteropolyacid, improves the hydrophobicity and stability of the catalyst, and makes the catalyst have a higher catalytic activity and selectivity. The heteropolyacid quaternary ammonium salt catalyst of the present invention is applied to the synthesis of BIPB, the reaction conditions are mild, the reaction time is shortened, the side reaction is reduced, the yield and purity of BIPB are improved, the process safety is high, and the production cost is reduced. At the same time, the heteropolyacid quaternary ammonium salt catalyst of the present invention reduces the corrosion of equipment, the catalyst is easily separated from the product, and is convenient for recycling; the process is simplified, the alkali washing and water washing links of the condensation liquid are reduced, and the discharge of a large amount of waste water is reduced, and the green production of the synthesis of BIPB can be realized.

[0151] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. A heteropolyacid quaternary ammonium salt catalyst, characterized in that The structure of the heteropolyacid quaternary ammonium salt catalyst is as follows: a H b XM c Y d Z e O 40 , where Q is a quaternary ammonium cation, represented by [R1R2R3R4N] + It represents that N is a nitrogen atom, R1, R2, R3, and R4 are selected from hydrogen atoms, linear or branched alkyl groups, and benzyl groups, and R1, R2, R3, and R4 are the same or different; M is a central metal atom, selected from at least one element of Mo and W; X is a heteroatom, selected from one or more elements of P, Si, As, and Ge, preferably one or more elements of P and Si; Y is a substituted metal atom, selected from one or more elements of Cr, V, Mn, Fe, and Zr, preferably one or more elements of V and Cr; Z is a substituted metal atom, selected from one or more elements of Ni, Co, Cu, Zn, and Cd, preferably one or more elements of Ni and Co; wherein a=1-3, b=0-2, c=0.1-10, d=1-6, e=1-6, preferably c=6-10, preferably d=2-5; preferably e=1-4.

2. The method for preparing a heteropolyacid quaternary ammonium salt catalyst according to claim 1, wherein: The following steps are involved: 1) According to the chemical formula Q a H b XM c Y d Z e O 40 The compound containing the elements required by each active component is calculated, dissolved in deionized water, and after uniform mixing, the pH of the liquid is adjusted to 1-5, preferably pH=2-4, to obtain a mixed solution A containing heteropolyacid. 2) Dissolve the quaternary ammonium salt in deionized water until it is completely dissolved to obtain solution B. 3) Slowly drop solution B into mixed solution A at 20-50° C. with stirring. After the dropwise addition, continue the reaction for 0.5-3 h. Filter the resulting precipitate, wash with deionized water, and vacuum dry at 45-55° C. to obtain the heteropolyacid quaternary ammonium salt catalyst.

3. The preparation method of heteropolyacid quaternary ammonium salt catalyst according to claim 2, characterized in that, In step 1), the compound containing the element required by the active component is one or more of the corresponding oxides, hydroxides, nitrates, chlorides, acetates and carbonates.

4. The preparation method of heteropolyacid quaternary ammonium salt catalyst according to claim 2, characterized in that, Step 1) The pH of the feed solution is adjusted to 1-5 with nitric acid.

5. The preparation method of heteropolyacid quaternary ammonium salt catalyst according to claim 2, characterized in that, The quaternary ammonium salt described in step 2) is selected from one or more of octadecyltrimethylammonium chloride, octadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, tetradecyltrimethylammonium chloride, and tetradecyltrimethylammonium bromide, preferably one or more of octadecyltrimethylammonium chloride and hexadecyltrimethylammonium chloride.

6. A method for synthesizing BIPB using the heteropolyacid quaternary ammonium salt catalyst described in claim 1, characterized in that: The method uses di-(2-hydroxyisopropyl)benzene and tert-butyl hydroperoxide aqueous solution as raw materials and heteropolyacid quaternary ammonium salt as catalyst to carry out a condensation reaction in an organic solvent, which specifically includes the following steps: 1) Adding tert-butyl hydroperoxide aqueous solution and dehydrating agent into a condensation reaction kettle, stirring and mixing evenly, standing to separate layers, and draining the bottom aqueous phase, the dehydration treatment of the tert-butyl hydroperoxide aqueous solution is completed. 2) Add di-(2-hydroxyisopropyl)benzene, an organic solvent and a quaternary ammonium salt catalyst of a heteropolyacid into a condensation reaction kettle, turn on the hot water in the jacket of the condensation reaction kettle to increase the temperature, turn on the vacuum pump to evacuate the kettle, and at the same time, bubbling nitrogen, stirring and decompressing the kettle under reflux to complete the condensation dehydration reaction. 3) When the condensation reaction is finished, add alkali solution with a mass concentration of 3-5% to terminate the reaction. 4) After the reaction is terminated, the condensation liquid is filtered, and the filtrate is distilled under reduced pressure to remove the solvent to obtain the product. The filter cake obtained by filtration is the heteropolyacid quaternary ammonium salt catalyst, which can be recycled.

7. The method for synthesizing BIPB using a heteropolyacid quaternary ammonium salt catalyst according to claim 6, characterized in that: The dehydrating agent is selected from one or more of sodium sulfate and sodium carbonate, and the weight ratio of the dehydrating agent to the aqueous solution of tert-butyl hydroperoxide is 0.01-0.05:

1.

8. The method for synthesizing BIPB using a heteropolyacid quaternary ammonium salt catalyst according to claim 6, characterized in that: The organic solvent is selected from one or more of cyclohexane and n-hexane, and the weight ratio of the organic solvent to di-(2-hydroxyisopropyl)benzene is 1.5-4.5:

1.

9. The method for synthesizing BIPB using a heteropolyacid quaternary ammonium salt catalyst according to claim 6, characterized in that: The proportions of each material are as follows: The molar ratio of di-(2-hydroxyisopropyl)benzene to tert-butyl hydroperoxide is 1:2.1-2.7; The weight ratio of di-(2-hydroxyisopropyl)benzene to heteropolyacid quaternary ammonium salt catalyst is 1:0.05% to 0.40%.

10. The use of heteropolyacid quaternary ammonium salt catalyst to synthesize BIPB according to claim 6, characterized in that: The condensation reaction temperature is 35 to 60°C, the vacuum degree is -0.02 to -0.08 MPa, and the reaction time is 1 to 5 hours.