Production method of di-tert-butyl peroxide

Abstract

The invention discloses a production method of di-tert-butyl peroxide, and belongs to the technical field of chemical production. The production method comprises the following steps: adding water into a tert-butyl hydroperoxide crude product for dilution to obtain a mixture containing an oil phase and a water phase; performing liquid separation on the mixture to obtain an oil-phase di-tert-butyl peroxide crude product and a water-phase tert-butyl hydroperoxide crude product; carrying out alkali washing, water washing and drying on the oil-phase di-tert-butyl peroxide crude product to obtain a di-tert-butyl peroxide finished product; and carrying out negative pressure light component removal and concentration on the water-phase tert-butyl hydroperoxide crude product to obtain a tert-butyl hydroperoxide finished product. According to the present invention, the process flow is simple, the tert-butyl hydroperoxide crude product is diluted and separated by adding water, and is simply washed to obtain the high-quality di-tert-butyl peroxide, such that the wastewater output is reduced, the tert-butyl hydroperoxide product is obtained through the light component removal and concentration extraction manner, and the water phase is reused in the system, such that the resource utilization rate is improved, and the production cost is reduced. And green and economical effects are realized.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical production, and more particularly to a method for producing di-tert-butyl peroxide. Background Art

[0002] Di-tert-butyl peroxide (DTBP) is used as a styrene polymerization agent, particularly as an initiator for the production of high-impact polystyrene and flame-retardant polyethylene foam. Tert-butyl hydroperoxide (TBHP) is primarily used as a catalyst, bleaching agent and deodorant, a crosslinker for unsaturated polyesters, a polymerization initiator, and a rubber vulcanizer.

[0003] Currently, tert-butyl hydroperoxide is synthesized using the hydrogen peroxide reaction method. This method involves mixing 70% hydrogen peroxide with tert-butyl alcohol and using 76% concentrated sulfuric acid as a catalyst. After a 30-minute reaction, the oil and water separate to produce a crude upper oil phase of tert-butyl hydroperoxide. The oil phase consists of tert-butyl hydroperoxide, water, and di-tert-butyl peroxide.

[0004] CN 112028805 A discloses a continuous production process for the continuous production of tert-butyl hydroperoxide and di-tert-butyl peroxide. The resulting mixture of tert-butyl alcohol, water, tert-butyl hydroperoxide, and di-tert-butyl peroxide is distilled to a rectifying tower to obtain the tert-butyl hydroperoxide product. The mixture of water, tert-butyl alcohol, and di-tert-butyl peroxide is separated in a reflux tank, and the oil layer is mixed with water before entering a No. 3 separation tank. The separated oil layer is di-tert-butyl peroxide. Patent CN 112521324A discloses a method for preparing di-tert-butyl peroxide. The crude product is washed with 30% sodium hydroxide solution, washed with water, and then dried over anhydrous magnesium sulfate to obtain di-tert-butyl peroxide. The above process CN 112028805 A uses a distillation tower, which consumes a lot of energy and has high separation requirements. Process CN 112521324 A uses high-concentration alkali dissolution and also requires the mother liquor after alkali washing to be treated. Acid needs to be added to recover tert-butyl hydroperoxide, and a large amount of acidic wastewater is produced, resulting in a waste of resources.

[0005] Therefore, how to develop a production method for di-tert-butyl peroxide and solve the shortcomings of the existing production methods is an urgent problem that those skilled in the art need to solve. Summary of the Invention

[0006] In view of this, the present invention provides a method for producing di-tert-butyl peroxide.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for producing di-tert-butyl peroxide comprises the following steps:

[0009] (1) diluting the crude tert-butyl hydroperoxide with water to obtain a mixture containing oil and water phases;

[0010] (2) separating the mixture to obtain a crude di-tert-butyl peroxide product in an oil phase and a crude tert-butyl hydroperoxide product in an aqueous phase;

[0011] (3) washing the crude di-tert-butyl peroxide oil phase with alkali, water, and drying to obtain a finished di-tert-butyl peroxide product;

[0012] (4) The crude tert-butyl hydroperoxide in the aqueous phase is concentrated under reduced pressure to obtain the finished tert-butyl hydroperoxide.

[0013] Furthermore, in step (1), the crude tert-butyl hydroperoxide has a content of tert-butyl hydroperoxide of 70-80 wt %, a content of di-tert-butyl peroxide of 10-20 wt %, and the balance being water.

[0014] Furthermore, in step (1), the mass of water added is 4.2-6.7 times that of the crude tert-butyl hydroperoxide.

[0015] Furthermore, in step (2), the content of di-tert-butyl peroxide in the crude di-tert-butyl peroxide oil phase is 97-98 wt %, and the content of tert-butyl hydroperoxide in the crude tert-butyl hydroperoxide aqueous phase is 9.5-15.5 wt %.

[0016] Furthermore, in step (3), the mass ratio of the crude di-tert-butyl peroxide in the oil phase to the alkaline washing solution used for alkali washing or the water used for water washing is 1:(0.8-1.2), the washing temperature of the alkaline washing or water washing is 20-30°C, and the washing time is 20-60min;

[0017] The alkaline washing solution is an aqueous solution of sodium hydroxide or potassium hydroxide, and the concentration of the alkaline washing solution is 3-10wt%.

[0018] Furthermore, in the above step (3), the desiccant used for drying is sodium sulfate.

[0019] Furthermore, in the above step (3), the content of di-tert-butyl peroxide in the finished di-tert-butyl peroxide product is 98.5-99 wt%.

[0020] Furthermore, in the above step (4), the content of tert-butyl hydroperoxide in the finished tert-butyl hydroperoxide product is 70-80 wt%.

[0021] Furthermore, in the above step (4), the specific steps of negative pressure degassing and concentration are:

[0022] The crude tert-butyl hydroperoxide in the aqueous phase is put into a light removal reactor, the vacuum degree is controlled at -0.08 MPa to -0.09 MPa, the temperature is 30 to 50°C, and the product is concentrated under reduced pressure to obtain the finished tert-butyl hydroperoxide. The residual bottom liquid is recycled to step (1).

[0023] Furthermore, in step (1), the preparation method of the crude tert-butyl hydroperoxide comprises the following steps: mixing a 70 wt% aqueous hydrogen peroxide solution with tert-butyl alcohol, adding 76 wt% concentrated sulfuric acid as a catalyst, reacting for 30 minutes, and separating the oil and water to obtain an oil phase, which is the crude tert-butyl hydroperoxide.

[0024] Furthermore, in step (1), the molar ratio of hydrogen peroxide, tert-butanol and sulfuric acid is 1:(0.8-1.2):(0.6-1.8), and the reaction temperature is 30-50°C.

[0025] The beneficial effects of the present invention are as follows: the process flow is simple, a crude tert-butyl hydroperoxide can be separated by dilution with water, and high-quality di-tert-butyl peroxide can be obtained by simple washing, thereby reducing the output of wastewater for separating di-tert-butyl peroxide and tert-butyl hydroperoxide by high-concentration alkali dissolution and acid precipitation, and the remaining tert-butyl hydroperoxide is obtained by light removal and concentration, and the aqueous phase is reused in the system, thereby improving resource utilization, reducing environmental pollution and resource waste, and achieving green conservation. DETAILED DESCRIPTION

[0026] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] Example 1

[0028] The production method of di-tert-butyl peroxide comprises the following steps:

[0029] (1) A 70 wt % aqueous hydrogen peroxide solution is mixed with tert-butyl alcohol, and concentrated sulfuric acid with a concentration of 76 wt % is added as a catalyst. The molar ratio of hydrogen peroxide, tert-butyl alcohol, and sulfuric acid is 1:1:1.2. The reaction temperature is 40° C., and after the reaction is carried out for 30 minutes, oil and water are separated to obtain an oil phase, namely, crude tert-butyl hydroperoxide. The crude tert-butyl hydroperoxide contains 75.2 wt % tert-butyl hydroperoxide and 20.5 wt % di-tert-butyl peroxide, with the remainder being water.

[0030] 1000 kg of crude tert-butyl hydroperoxide was put into a reactor and diluted with 4200 kg of water to obtain a mixture containing oil and water phases;

[0031] (2) separating the mixture to obtain 206 kg of crude di-tert-butyl peroxide in the oil phase and 4994 kg of crude tert-butyl hydroperoxide in the aqueous phase, wherein the content of di-tert-butyl peroxide in the crude di-tert-butyl peroxide in the oil phase is 97.6 wt %, and the content of tert-butyl hydroperoxide in the crude tert-butyl hydroperoxide in the aqueous phase is 15.02 wt %;

[0032] (3) The crude di-tert-butyl peroxide oil phase was put into a washing kettle, and 170 kg of a 3 wt % sodium hydroxide aqueous solution was added and stirred at 20° C. for 20 min. After the alkali washing was completed, the aqueous phase was removed, and the product after the alkali washing was added with 170 kg of water at 20° C. and stirred for 20 min. After the water washing was completed, the aqueous phase was separated, and the product after the water washing was added with sodium sulfate and dried to a water content of ≤0.5% to obtain 204 kg of finished di-tert-butyl peroxide. The content of di-tert-butyl peroxide in the finished di-tert-butyl peroxide was determined by gas chromatography to be 98.5 wt %; the yield was 98%;

[0033] (4) The crude tert-butyl hydroperoxide in the aqueous phase was concentrated under reduced pressure to obtain 889 kg of finished tert-butyl hydroperoxide. The content of the finished tert-butyl hydroperoxide in the finished tert-butyl hydroperoxide was 79.5 wt %, and the yield was 94%.

[0034] The specific steps of negative pressure desalination and concentration are:

[0035] The crude tert-butyl hydroperoxide in the aqueous phase is put into a light removal reactor, the vacuum degree is controlled at -0.09 MPa, the temperature is 30°C, and the product is concentrated under reduced pressure to obtain the finished tert-butyl hydroperoxide. The residual bottom liquid is recycled to step (1).

[0036] After light removal and concentration, 4070 kg of residual still bottom liquid was obtained. The tert-butyl hydroperoxide content in the residual still bottom liquid was 0.8%, and the total yield was 98.3%. The total yield refers to the calculated value of the sum of the amount of tert-butyl hydroperoxide in the collected tert-butyl hydroperoxide product and the amount of tert-butyl hydroperoxide remaining in the still bottom liquid divided by the amount of tert-butyl hydroperoxide in the crude tert-butyl hydroperoxide product. The calculation formula is:

[0037] (889*79.5%+4070*0.8%) / (1000*75.2%)=98.3%.

[0038] Example 2

[0039] The production method of di-tert-butyl peroxide comprises the following steps:

[0040] (1) A 70 wt % aqueous hydrogen peroxide solution is mixed with tert-butyl alcohol, and concentrated sulfuric acid with a concentration of 76 wt % is added as a catalyst. The molar ratio of hydrogen peroxide, tert-butyl alcohol, and sulfuric acid is 1:1:1.2. The reaction temperature is 40° C., and after the reaction is carried out for 30 minutes, oil and water are separated to obtain an oil phase, namely, crude tert-butyl hydroperoxide. The crude tert-butyl hydroperoxide contains 75.2 wt % tert-butyl hydroperoxide and 20.5 wt % di-tert-butyl peroxide, with the remainder being water.

[0041] 1000 kg of crude tert-butyl hydroperoxide was put into a reactor and diluted with 5200 kg of water to obtain a mixture containing oil and water phases;

[0042] (2) separating the mixture to obtain 207 kg of crude di-tert-butyl peroxide in the oil phase and 5993 kg of crude tert-butyl hydroperoxide in the aqueous phase, wherein the content of di-tert-butyl peroxide in the crude di-tert-butyl peroxide in the oil phase is 97.8 wt %, and the content of tert-butyl hydroperoxide in the crude tert-butyl hydroperoxide in the aqueous phase is 12.5 wt %;

[0043] (3) The crude di-tert-butyl peroxide oil phase was put into a washing kettle, and 200 kg of 6 wt% sodium hydroxide aqueous solution was added and stirred at 25° C. for 40 min. After the alkali washing was completed, the aqueous phase was removed, and the product after the alkali washing was added with 200 kg of water and stirred at 25° C. for 40 min. After the water washing was completed, the aqueous phase was separated, and the product after the water washing was added with sodium sulfate and dried to a water content of ≤0.5% to obtain 205 kg of finished di-tert-butyl peroxide. The content of di-tert-butyl peroxide in the finished di-tert-butyl peroxide was determined by gas chromatography to be 98.7 wt%; the yield was 98.7%;

[0044] (4) The crude tert-butyl hydroperoxide in the aqueous phase was concentrated under reduced pressure to obtain 952 kg of finished tert-butyl hydroperoxide. The content of the finished tert-butyl hydroperoxide in the finished tert-butyl hydroperoxide was 74.8 wt %, and the yield was 94.7%.

[0045] The specific steps of negative pressure desalination and concentration are:

[0046] The crude tert-butyl hydroperoxide in the aqueous phase was placed in a degassing reactor, the vacuum was maintained at -0.08 MPa, the temperature was maintained at 50°C, and the product was concentrated under reduced pressure to obtain the finished tert-butyl hydroperoxide. The residual bottom liquid was reused in step (1). After degassing and concentration, 5000 kg of residual bottom liquid was obtained. The tert-butyl hydroperoxide content in the residual bottom liquid was 0.6%, and the total yield was 98.7%.

[0047] Example 3

[0048] The production method of di-tert-butyl peroxide comprises the following steps:

[0049] (1) A 70 wt % aqueous hydrogen peroxide solution is mixed with tert-butyl alcohol, and concentrated sulfuric acid with a concentration of 76 wt % is added as a catalyst. The molar ratio of hydrogen peroxide, tert-butyl alcohol, and sulfuric acid is 1:1:1.2. The reaction temperature is 40° C., and after the reaction is carried out for 30 minutes, oil and water are separated to obtain an oil phase, namely, crude tert-butyl hydroperoxide. The crude tert-butyl hydroperoxide contains 75.2 wt % tert-butyl hydroperoxide and 20.5 wt % di-tert-butyl peroxide, with the remainder being water.

[0050] 1000 kg of crude tert-butyl hydroperoxide was put into a reactor and diluted with 6700 kg of water to obtain a mixture containing oil and water phases;

[0051] (2) separating the mixture to obtain 209 kg of crude di-tert-butyl peroxide in the oil phase and 7491 kg of crude tert-butyl hydroperoxide in the aqueous phase, wherein the content of di-tert-butyl peroxide in the crude di-tert-butyl peroxide in the oil phase is 98 wt %, and the content of tert-butyl hydroperoxide in the crude tert-butyl hydroperoxide in the aqueous phase is 9.98 wt %;

[0052] (3) The crude di-tert-butyl peroxide oil phase was put into a washing kettle, and 240 kg of a 3 wt % sodium hydroxide aqueous solution was added and stirred at 30° C. for 60 min. After the alkali washing was completed, the aqueous phase was removed, and the product after the alkali washing was added with 240 kg of water and stirred at 30° C. for 60 min. After the water washing was completed, the aqueous phase was separated, and the product after the water washing was added with sodium sulfate and dried to a water content of ≤0.5% to obtain 206 kg of finished di-tert-butyl peroxide. The content of di-tert-butyl peroxide in the finished di-tert-butyl peroxide was determined by gas chromatography to be 99 wt %; the yield was 99.5%;

[0053] (4) The crude tert-butyl hydroperoxide in the aqueous phase was concentrated under reduced pressure to obtain 1020 kg of finished tert-butyl hydroperoxide. The content of the finished tert-butyl hydroperoxide in the finished tert-butyl hydroperoxide was 70.5 wt %, and the yield was 95.6%.

[0054] The specific steps of negative pressure desalination and concentration are:

[0055] The crude tert-butyl hydroperoxide in the aqueous phase was placed in a degassing reactor, the vacuum was maintained at -0.085 MPa, the temperature was maintained at 40°C, and the product was concentrated under reduced pressure to obtain the finished tert-butyl hydroperoxide. The residual bottom liquid was recycled to step (1). After degassing and concentration, 6400 kg of residual bottom liquid was obtained. The tert-butyl hydroperoxide content in the residual bottom liquid was 0.4%, and the total yield was 99%.

[0056] Comparative Example 1

[0057] 1000 kg of crude tert-butyl hydroperoxide is put into a reactor, wherein the content of di-tert-butyl peroxide is 20.5%, the content of tert-butyl hydroperoxide is 75.2%, and the balance is water. 1200 kg of 30 wt% sodium hydroxide solution is added for washing and reaction to obtain crude tert-butyl hydroperoxide sodium salt and crude di-tert-butyl peroxide. The reaction temperature is 25° C. The crude di-tert-butyl peroxide is washed with water and dried to obtain 194.7 kg of finished di-tert-butyl peroxide with a content of 95.8% and a yield of 91%. The crude sodium salt of tert-butyl hydroperoxide is washed with alkali, and sulfuric acid is added to the sodium salt to acidify it to pH=1 to obtain 882 kg of finished tert-butyl hydroperoxide. The tert-butyl hydroperoxide content in the finished tert-butyl hydroperoxide is 78.5%, and the yield is 92.1%. A large amount of acidified mother liquor is generated.

[0058] Comparative Example 2

[0059] 1000 kg of crude tert-butyl hydroperoxide was added to a reactor. The di-tert-butyl peroxide content was 20.5%, the tert-butyl hydroperoxide content was 75.2%, and the balance was water. After adding 4000 kg of water, the separation was poor, yielding 4785 kg of turbid aqueous phase with 0.2% di-tert-butyl peroxide and 15.2% tert-butyl hydroperoxide. The oil phase yielded 210 kg of turbid oil with 81.8% di-tert-butyl peroxide and 11.9% tert-butyl hydroperoxide, which did not meet normal specifications.

[0060] Comparative Example 3

[0061] 1000 kg of crude tert-butyl hydroperoxide was put into a reactor, wherein the content of di-tert-butyl peroxide was 20.5%, the content of tert-butyl hydroperoxide was 75.2%, and the balance was water. 7000 kg of water was added to separate 209 kg of crude di-tert-butyl peroxide, wherein the content of di-tert-butyl peroxide was 98%. The crude di-tert-butyl peroxide was put into a washing kettle, and 240 kg of 3% sodium hydroxide solution and water were added, and the mixture was stirred and washed at 30° C. for 60 minutes. After washing, the water phase was separated and dried with sodium sulfate to a water content of ≤0.5%, thereby obtaining 206 kg of di-tert-butyl peroxide, wherein the content of di-tert-butyl peroxide was 99% as detected by gas chromatography, and the yield was 99.5%. 7790 kg of crude tert-butyl hydroperoxide was separated, with a tert-butyl hydroperoxide content of 9.6%. After light removal and concentration, 1100 kg of finished tert-butyl hydroperoxide was obtained, with a tert-butyl hydroperoxide content of 64.8% and a yield of 94.8%. A total of 6600 kg of residual bottom liquid was left, with a tert-butyl hydroperoxide content of 0.1%, for a total yield of 95.7%. The tert-butyl hydroperoxide content of the concentrated product was low, not meeting the required tert-butyl hydroperoxide content of 70-80%.

[0062] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for producing di-tert-butyl peroxide, characterized in that: The following steps are involved: (1) adding water to dilute the crude tert-butyl hydroperoxide to obtain a mixture containing oil and water phases; (2) separating the mixture to obtain a crude product of di-tert-butyl peroxide in an oil phase and a crude product of tert-butyl hydroperoxide in an aqueous phase; (3) washing the crude di-tert-butyl peroxide product in the oil phase with alkali, water, and drying to obtain a finished di-tert-butyl peroxide product; (4) The crude tert-butyl hydroperoxide in the aqueous phase is concentrated by vacuum stripping to obtain the finished tert-butyl hydroperoxide.

2. A method for producing di-tert-butyl peroxide according to claim 1, characterized in that: In step (1), in the crude tert-butyl hydroperoxide, the content of tert-butyl hydroperoxide is 70-80wt%, the content of di-tert-butyl peroxide is 10-20wt%, and the balance is water.

3. A method for producing di-tert-butyl peroxide according to claim 1, characterized in that: In step (1), the mass of water added is 4.2-6.7 times that of the crude tert-butyl hydroperoxide.

4. A method for producing di-tert-butyl peroxide according to claim 1, characterized in that: In step (2), the content of di-tert-butyl peroxide in the crude di-tert-butyl peroxide product in the oil phase is 97-98 wt %, and the content of tert-butyl hydroperoxide in the crude tert-butyl hydroperoxide product in the water phase is 9.5-15.5 wt %.

5. A method for producing di-tert-butyl peroxide according to claim 1, characterized in that: In step (3), the mass ratio of the crude di-tert-butyl peroxide in the oil phase to the alkaline washing liquid used for alkali washing or the water used for water washing is 1:(0.8-1.2), the washing temperature of the alkaline washing or water washing is 20-30° C., and the washing time is 20-60 min; The alkaline washing solution is an aqueous solution of sodium hydroxide or potassium hydroxide, and the concentration of the alkaline washing solution is 3-10wt%.

6. A method for producing di-tert-butyl peroxide according to claim 1, characterized in that: In the step (3), the desiccant used for drying is sodium sulphate.

7. A method for producing di-tert-butyl peroxide according to claim 1, characterized in that: In the step (3), the content of di-tert-butyl peroxide in the finished di-tert-butyl peroxide product is 98.5-99wt%.

8. A method for producing di-tert-butyl peroxide according to claim 1, characterized in that: In the step (4), the content of tert-butyl hydroperoxide in the finished tert-butyl hydroperoxide is 70-80 wt %.

9. A method for producing di-tert-butyl peroxide according to claim 1, characterized in that: In the step (4), the specific steps of negative pressure desalination and concentration are as follows: The crude tert-butyl hydroperoxide in the aqueous phase is placed in a light removal kettle, the vacuum degree is controlled at -0.08 MPa to -0.09 MPa, the temperature is 30 to 50°C, and the product is concentrated under reduced pressure to obtain the tert-butyl hydroperoxide product. The residual bottom liquid is recycled to step (1).

10. The method for producing di-tert-butyl peroxide according to claim 1, characterized in that: In step (1), the preparation method of the crude tert-butyl hydroperoxide comprises the following steps: mixing a 70wt% aqueous hydrogen peroxide solution with tert-butyl alcohol, and adding 76wt% concentrated sulfuric acid as a catalyst, reacting for 30 minutes, separating oil from water to obtain an oil phase, which is the crude tert-butyl hydroperoxide.