Preparation method of tert-butyl peroxyisobutyrate

Abstract

The invention belongs to the technical field of acyclic compounds, and particularly relates to a preparation method of tert-butyl peroxyisobutyrate. Stirring and cooling a solvent, a tert-butyl hydroperoxide aqueous solution and deionized water to obtain a mixed solution A; adding liquid caustic soda and a solid base catalyst into the mixed solution A under a stirring condition, and continuously stirring for reaction to obtain a mixed solution B; under the stirring condition, isobutyryl chloride and a water-soluble distributing agent are added into the mixed solution B, stirring reaction continues to be conducted, and a mixed solution C is obtained; standing and layering the mixed solution C, separating to obtain a tert-butyl peroxyisobutyrate crude product, and refining the tert-butyl peroxyisobutyrate crude product to obtain the tert-butyl peroxyisobutyrate. According to the method, the raw material utilization rate is increased, the reaction speed is increased, the reaction time is shortened, and the product yield is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of acyclic compounds, and particularly relates to a preparation method of tert-butyl peroxyisobutyrate. Background Art

[0002] Tert-butyl peroxyisobutyrate is abbreviated as TBPI, and its chemical formula is C8H 16 O3. Tert-butyl peroxyisobutyrate is an organic peroxide and can be used as a polymerization initiator for ethylene and styrene. Tert-butyl peroxyisobutyrate has poor thermal stability and there is a risk of combustion or explosion during storage and transportation.

[0003] Chinese Patent CN 115536565A discloses a preparation method of tert-butyl peroxybenzoate, which includes the following steps: (1) adding a dehydrating agent to the tert-butyl hydroperoxide solution for dehydration, separating the liquid, and taking the organic layer; (2) adding a sodium hydroxide solution to the organic layer to adjust the pH of the mixed solution to alkaline, then adding a phase transfer catalyst and mixing evenly; (3) mixing benzoyl chloride and a desensitizer evenly; (4) simultaneously adding the mixed solution in step (3) and a sodium hydroxide solution dropwise to the mixed solution in step (2), and keeping the temperature for reaction after dropping; (5) separating the liquid of the reaction solution obtained in step (4) to take the organic layer, and the organic layer is successively subjected to alkali washing, water washing and vacuum flash drying to obtain the finished product of tert-butyl peroxybenzoate. This patent needs to remove the water in the tert-butyl hydroperoxide solution first, and the operation steps are complicated, which is not conducive to reducing the overall reaction time. Summary of the Invention

[0004] The purpose of the present invention is to provide a preparation method of tert-butyl peroxyisobutyrate, which improves the utilization rate of raw materials, speeds up the reaction rate, reduces the reaction time, and has a high product yield.

[0005] The preparation method of tert-butyl peroxyisobutyrate described in the present invention includes the following steps: (1) A solvent, an aqueous solution of tert-butyl hydroperoxide and deionized water are stirred and cooled to obtain a mixed solution A; (2) Under stirring conditions, liquid alkali and a solid base catalyst are added to the mixed solution A, and stirring and reaction are continued to obtain a mixed solution B; (3) Under stirring conditions, isobutyryl chloride and a water-soluble distributor are added to the mixed solution B, and stirring and reaction are continued to obtain a mixed solution C; (4) The mixed solution C is allowed to stand and layer, and after separation, a crude product of tert-butyl peroxyisobutyrate is obtained, and the crude product of tert-butyl peroxyisobutyrate is refined to obtain tert-butyl peroxyisobutyrate.

[0006] In step (1), the solvent is one or more of dodecane, n-hexane or silicone oil, the concentration of the aqueous solution of tert-butyl hydroperoxide is 70-99 wt.%, and the temperature of stirring and cooling is 0-20 °C.

[0007] In step (1), the mass ratio of the aqueous solution of tert-butyl hydroperoxide, the solvent and deionized water is 0.3 - 0.5:0 - 2:0.28 - 0.5.

[0008] In step (2), the liquid base is an aqueous solution of sodium hydroxide or an aqueous solution of potassium hydroxide, the concentration of the liquid base is 20 - 50 wt.%, and the mass ratio of the liquid base to the aqueous solution of tert-butyl hydroperoxide in step (1) is 22 - 58:24 - 35.

[0009] In step (2), the solid base catalyst is magnesium aluminum hydrotalcite of tert-butanol, and the mass of the solid base catalyst is 0.9 - 10% of the mass of the liquid base.

[0010] In step (2), the addition time is 10 - 30 min, and the addition temperature is 0 - 20 °C; the temperature for continuous stirring reaction is 5 - 15 °C, and the time for continuous stirring reaction is 10 - 30 min.

[0011] In step (3), the mass ratio of isobutyryl chloride to the liquid base in step (2) is 1:0.82 - 2.06.

[0012] In step (3), the water-soluble partitioning agent is one or both of tetramethylammonium chloride and methyltributylammonium chloride, and the mass ratio of isobutyryl chloride to the water-soluble partitioning agent is 1:0.01 - 0.03.

[0013] In step (3), the addition time is 10 - 30 min, and the addition temperature is 0 - 20 °C; the temperature for continuous stirring reaction is 5 - 20 °C, and the time for continuous stirring reaction is 10 - 120 min.

[0014] In step (4), the temperature for static separation is 0 - 15 °C, and the time for static separation is 20 - 30 min; for refining, the crude tert-butyl peroxyisobutyrate is washed with an alkali solution, an aqueous solution of sodium bicarbonate and deionized water respectively. Among them, the alkali solution is one or both of a sodium hydroxide solution and a potassium hydroxide solution, the concentration of the alkali solution is 5 wt.% to the saturated concentration, the concentration of the aqueous solution of sodium bicarbonate is 1 - 10 wt.%, and the number of washing times is 2 - 3 times; the pH value of the tert-butyl peroxyisobutyrate after washing is 7 - 8.

[0015] The beneficial effects of the present invention are as follows: The magnesium aluminum hydrotalcite of tert-butanol adopted in the present invention belongs to the layered double hydroxide structure, has a special ionic layer arrangement, and the layered structure greatly increases the specific surface area of the magnesium aluminum hydrotalcite of tert-butanol. The high valence of the active sites in the magnesium aluminum hydrotalcite of tert-butanol and the high specific surface area of the magnesium aluminum hydrotalcite of tert-butanol make the active sites (Mg 2+ and Al 3 +) It is easier to adsorb chloride ions (Cl in isobutyryl chloride - ) to form unstable intermediate transition states MgCl2 and AlCl3, promoting the decomposition of isobutyryl chloride and accelerating the reaction rate; when the metal peroxide intermediate (tert-butyl hydroperoxide salt) formed by the reaction of liquid alkali and tert-butyl hydroperoxide is attracted to the vicinity of the active site, it reacts with the isobutyryl group to form tert-butyl peroxyisobutyrate. At the same time, sodium ions or potassium ions react with the unstable intermediate transition states MgCl2 and AlCl3 to form NaCl or KCl and desorb from the active site, and the active site is reactivated, forming a synergistic catalysis between the liquid alkali and the solid base catalyst.

[0016] After the introduction of tert-butoxy groups into the interlayer of magnesium-aluminum tert-butoxide hydrotalcite used in the present invention, the magnesium-aluminum tert-butoxide hydrotalcite exhibits stronger basicity than ordinary hydrotalcite, and thus has more excellent base catalytic performance. At the same time, the use of magnesium-aluminum tert-butoxide hydrotalcite will not introduce new impurities.

[0017] tert-Butyl hydroperoxide also belongs to organic peroxides, which will decompose to produce impurities such as tert-butanol. After the introduction of tert-butoxy groups into the interlayer of magnesium-aluminum tert-butoxide hydrotalcite used in the present invention, the decomposition of tert-butyl hydroperoxide will be inhibited, the raw material utilization rate will be improved, and the economy is good.

[0018] The addition of a water-soluble distributor further accelerates the ion exchange between the organic phase and the inorganic phase, greatly accelerating the reaction rate and reducing the reaction time. Isobutyryl chloride is insoluble in water, and tert-butyl hydroperoxide exists in the form of an aqueous solution. The tetramethylammonium cation [(CH3)4N of the water-soluble distributor such as tetramethylammonium chloride (TMAC) + has amphiphilicity: the cationic head can form an ion pair with the conjugate base of tert-butyl hydroperoxide (tert-butoxy anion (CH3)3COO in the aqueous phase - ) through electrostatic interaction, and its four methyl side chains enable it to dissolve in the organic phase. Therefore, TMAC transfers the nucleophile (CH3)3COO in the aqueous phase - to the organic phase, where it undergoes an acylation reaction with isobutyryl chloride to form TBPI. The phase transfer effect enables the two-phase reactants that were originally isolated to come into full contact, and the reaction rate is increased. In the aqueous phase, the dissociation of tert-butyl hydroperoxide is limited by its weak acidity (pKa≈12), while the cation [(CH3)4N of TMAC + can form a tight ion pair with (CH3)3COO - to reduce its solvation effect and enhance its nucleophilicity. This activation effect makes the acylation reaction easier to proceed, especially significant under low-temperature (0-10 °C) conditions. In addition, the reaction of isobutyryl chloride and tert-butyl hydroperoxide releases HCl, which needs to be neutralized with a base (such as NaOH). After HCl is generated in the organic phase, the cation [(CH3)4N of TMAC + reacts with Cl- Combined to form an ion pair, accelerating the transfer of HCl from the organic phase to the aqueous phase and avoiding its inhibition of the reaction. TMAC can also reduce the excessive OH in the aqueous phase - , preventing the excessive decomposition of tert-butyl hydroperoxide under alkaline conditions and thus increasing the product yield. The product yield of the present invention reaches over 90%. Detailed implementation mode

[0019] The present invention will be further described below in conjunction with embodiments.

[0020] Embodiment 1 (1) 40.02 g of dodecane, 30.55 g of an aqueous solution of tert-butyl hydroperoxide with a concentration of 80 wt.%, and 30.01 g of deionized water were stirred and cooled to 0 °C to obtain a mixed solution A; (2) Under stirring conditions, 22.85 g of an aqueous solution of sodium hydroxide with a concentration of 50 wt.% and 2.28 g of magnesium aluminum hydrotalcite tert-butoxide were added to the mixed solution A. The addition temperature was 0 °C, the addition time was 10 min, and after the addition, stirring was continued at 5 °C for 30 min to obtain a mixed solution B; (3) Under stirring conditions, 27.79 g of isobutyryl chloride and 0.28 g of tetramethylammonium chloride were added to the mixed solution B. The addition time was 10 min, the addition temperature was 20 °C, and after the addition, stirring was continued at 20 °C for 30 min to obtain a mixed solution C; (4) The mixed solution C was allowed to stand at 0 °C for 30 min and layered. After separating and removing the mother liquor, a crude product of tert-butyl isobutyrate peroxide was obtained. The crude product of tert-butyl isobutyrate peroxide was washed three times with an aqueous solution of sodium hydroxide with a concentration of 5 wt.%, an aqueous solution of sodium bicarbonate with a concentration of 1 wt.%, and deionized water to obtain 77.47 g of a solvent-type tert-butyl isobutyrate peroxide product. After testing, the content of pure tert-butyl isobutyrate peroxide in the solvent-type tert-butyl isobutyrate peroxide product was 49.5 wt.%, the pH value was 7.1, and the chlorine content was 77 ppm. After removing the solvent from the solvent-type tert-butyl isobutyrate peroxide product, 37.45 g of a tert-butyl isobutyrate peroxide product was obtained. The product yield was calculated to be 90%.

[0021] Embodiment 2 (1) 40.02 g of n-hexane, 24.68 g of an aqueous solution of tert-butyl hydroperoxide with a concentration of 99 wt.%, and 40.02 g of deionized water were stirred and cooled to 15 °C to obtain a mixed solution A; (2) Under stirring conditions, 57.13 g of an aqueous solution of potassium hydroxide with a concentration of 20 wt.% and 0.57 g of magnesium aluminum hydrotalcite tert-butoxide were added to the mixed solution A. The addition temperature was 15 °C, the addition time was 30 min, and after the addition, stirring was continued at 15 °C for 10 min to obtain a mixed solution B; (3) Under stirring conditions, 27.79 g of isobutyryl chloride and 0.56 g of tetramethylammonium chloride were added to the mixed solution B. The addition time was 30 min, the addition temperature was 0 °C, and after the addition, the mixture was stirred at 5 °C for 120 min to obtain a mixed solution C; (4) The mixed solution C was allowed to stand at 5 °C for 25 min and then layered. After separating and removing the mother liquor, a crude product of tert-butyl peroxyisobutyrate was obtained. The crude product of tert-butyl peroxyisobutyrate was washed three times with saturated potassium hydroxide solution, 10 wt.% aqueous sodium bicarbonate solution, and deionized water, respectively, to obtain 77.88 g of a solvent-type tert-butyl peroxyisobutyrate product. After testing, the content of pure tert-butyl peroxyisobutyrate in the solvent-type tert-butyl peroxyisobutyrate product was 50.02 wt.%, the pH value was 7.3, and the chlorine content was 88 ppm. After removing the solvent from the solvent-type tert-butyl peroxyisobutyrate product, 37.86 g of a tert-butyl peroxyisobutyrate product was obtained. The product yield was calculated to be 91%.

[0022] Example 3 (1) 150.34 g of silicone oil, 34.91 g of an aqueous solution of tert-butyl hydroperoxide with a concentration of 70 wt.%, and 23.34 g of deionized water were stirred and cooled to 20 °C to obtain a mixed solution A; (2) Under stirring conditions, 32.65 g of an aqueous sodium hydroxide solution with a concentration of 35 wt.% and 1.63 g of magnesium aluminum hydrotalcite tert-butoxide were added to the mixed solution A. The addition temperature was 20 °C, the addition time was 20 min, and after the addition, the mixture was stirred at 10 °C for 20 min to obtain a mixed solution B; (3) Under stirring conditions, 27.79 g of isobutyryl chloride and 0.60 g of methyltributylammonium chloride were added to the mixed solution B. The addition time was 20 min, the addition temperature was 15 °C, and after the addition, the mixture was stirred at 15 °C for 60 min to obtain a mixed solution C; (4) The mixed solution C was allowed to stand at 15 °C for 20 min and then layered. After separating and removing the mother liquor, a crude product of tert-butyl peroxyisobutyrate was obtained. The crude product of tert-butyl peroxyisobutyrate was washed three times with a 5 wt.% sodium hydroxide solution, a 3 wt.% aqueous sodium bicarbonate solution, and deionized water, respectively, to obtain 187.98 g of a solvent-type tert-butyl peroxyisobutyrate product. After testing, the content of pure tert-butyl peroxyisobutyrate in the solvent-type tert-butyl peroxyisobutyrate product was 20.06 wt.%, the pH value was 7.2, and the chlorine content was 84 ppm. After removing the solvent from the solvent-type tert-butyl peroxyisobutyrate product, 37.64 g of a tert-butyl peroxyisobutyrate product was obtained. The product yield was calculated to be 90.5%.

[0023] Example 4 (1) 30.55 g of an aqueous solution of tert-butyl hydroperoxide with a concentration of 80 wt.% and 30.01 g of deionized water were stirred and cooled to 0 °C to obtain a mixed solution A; (2) Under stirring conditions, 22.85 g of an aqueous sodium hydroxide solution with a concentration of 50 wt.% and 1.14 g of magnesium aluminum hydrotalcite tert-butoxide were added to the mixed solution A. The addition temperature was 0 °C, the addition time was 10 min, and after the addition, stirring was continued at 5 °C for 30 min to obtain a mixed solution B; (3) Under stirring conditions, 27.79 g of isobutyryl chloride and 0.30 g of methyltributylammonium chloride were added to the mixed solution B. The addition time was 10 min, the addition temperature was 15 °C, and after the addition, stirring was continued at 20 °C for 10 min to obtain a mixed solution C; (4) The mixed solution C was allowed to stand at 10 °C for 25 min and layered. After separating and removing the mother liquor, a crude product of tert-butyl isobutyrate peroxide was obtained. The crude product of tert-butyl isobutyrate peroxide was washed three times with a sodium hydroxide solution with a concentration of 5 wt.%, an aqueous sodium bicarbonate solution with a concentration of 1 wt.% and deionized water to obtain 37.59 g of a tert-butyl isobutyrate peroxide product. After testing, the content of tert-butyl isobutyrate peroxide was 98.86 wt.%, the pH value was 7.2, and the chlorine content was 76 ppm. The product yield was calculated to be 90.4%.

[0024] Comparative Example 1 (1) 40.02 g of dodecane, 30.55 g of an aqueous solution of tert-butyl hydroperoxide with a concentration of 80 wt.% and 30.01 g of deionized water were stirred and cooled to 0 °C to obtain a mixed solution A; (2) Under stirring conditions, 22.85 g of an aqueous sodium hydroxide solution with a concentration of 50 wt.% was added to the mixed solution A. The addition temperature was 0 °C, the addition time was 10 min, and after the addition, stirring was continued at 5 °C for 30 min to obtain a mixed solution B; (3) Under stirring conditions, 27.79 g of isobutyryl chloride and 0.28 g of tetramethylammonium chloride were added to the mixed solution B. The addition time was 10 min, the addition temperature was 20 °C, and after the addition, stirring was continued at 20 °C for 60 min to obtain a mixed solution C; (4)The mixed solution C was allowed to stand at 0 °C for 30 min and was separated into layers. After removing the mother liquor, the crude tert-butyl peroxyisobutyrate was obtained. The crude tert-butyl peroxyisobutyrate was washed three times with a sodium hydroxide solution with a concentration of 5 wt.%, an aqueous sodium bicarbonate solution with a concentration of 1 wt.% and deionized water, and 74.45 g of the solvent-type tert-butyl peroxyisobutyrate product was obtained. It was detected that the content of pure tert-butyl peroxyisobutyrate in the solvent-type tert-butyl peroxyisobutyrate product was 47.17 wt.%, the pH value was 7.1, and the chlorine content was 98 ppm. After removing the solvent in the solvent-type tert-butyl peroxyisobutyrate product, 34.43 g of the tert-butyl peroxyisobutyrate product was obtained. The product yield was calculated to be 82.8%.

[0025] Comparative Example 2 (1)40.02 g of dodecane, 30.55 g of an aqueous solution of tert-butyl hydroperoxide with a concentration of 80 wt.% and 30.01 g of deionized water were stirred and cooled to 0 °C to obtain a mixed solution A; (2)Under stirring conditions, 22.85 g of an aqueous sodium hydroxide solution with a concentration of 50 wt.% and 2.28 g of magnesium-aluminum hydrotalcite tert-butoxide were added to the mixed solution A. The addition temperature was 0 °C, the addition time was 10 min, and after the addition, stirring was continued at 5 °C for 30 min to obtain a mixed solution B; (3)Under stirring conditions, 27.79 g of isobutyryl chloride was added to the mixed solution B. The addition time was 10 min, the addition temperature was 20 °C, and after the addition, stirring was continued at 20 °C for 50 min to obtain a mixed solution C; (4)The mixed solution C was allowed to stand at 0 °C for 30 min and was separated into layers. After removing the mother liquor, the crude tert-butyl peroxyisobutyrate was obtained. The crude tert-butyl peroxyisobutyrate was washed three times with a sodium hydroxide solution with a concentration of 5 wt.%, an aqueous sodium bicarbonate solution with a concentration of 1 wt.% and deionized water, and 73.45 g of the solvent-type tert-butyl peroxyisobutyrate product was obtained. It was detected that the content of pure tert-butyl peroxyisobutyrate in the solvent-type tert-butyl peroxyisobutyrate product was 47.13 wt.%, the pH value was 7.3, and the chlorine content was 104 ppm. After removing the solvent in the solvent-type tert-butyl peroxyisobutyrate product, 33.43 g of the tert-butyl peroxyisobutyrate product was obtained. The product yield was calculated to be 80.4%.

Claims

1. A preparation method of tert-butyl peroxyisobutyrate, characterized in that It includes the following steps: (1) A solvent, an aqueous solution of tert-butyl hydroperoxide, and deionized water are stirred and cooled to obtain a mixed solution A; (2) Under stirring conditions, liquid alkali and a solid base catalyst are added to the mixed solution A, and stirring and reaction are continued to obtain a mixed solution B; (3) Under stirring conditions, isobutyryl chloride and a water-soluble distributor are added to the mixed solution B, and stirring and reaction are continued to obtain a mixed solution C; (4) The mixed solution C is allowed to stand and layer, and after separation, a crude product of tert-butyl peroxyisobutyrate is obtained, and the crude product of tert-butyl peroxyisobutyrate is refined to obtain tert-butyl peroxyisobutyrate.

2. The preparation method of tert-butyl peroxyisobutyrate according to claim 1, characterized in that In step (1), the solvent is one or more of dodecane, n-hexane, or silicone oil, the concentration of the aqueous solution of tert-butyl hydroperoxide is 70-99 wt.%, and the temperature for stirring and cooling is 0-20 °C.

3. The preparation method of tert-butyl peroxyisobutyrate according to claim 1, wherein In step (1), the mass ratio of the aqueous solution of tert-butyl hydroperoxide, the solvent, and deionized water is 0.3-0.5:0-2:0.28-0.

5.

4. The preparation method of tert-butyl peroxyisobutyrate according to claim 1, characterized in that In step (2), the liquid alkali is an aqueous solution of sodium hydroxide or an aqueous solution of potassium hydroxide, the concentration of the liquid alkali is 20-50 wt.%, and the mass ratio of the liquid alkali to the aqueous solution of tert-butyl hydroperoxide in step (1) is 22-58:24-35.

5. The preparation method of tert-butyl peroxyisobutyrate according to claim 1, wherein In step (2), the solid base catalyst is magnesium aluminum hydrotalcite of tert-butanol, and the mass of the solid base catalyst is 0.9-10% of the mass of the liquid alkali.

6. The preparation method of tert-butyl peroxyisobutyrate according to claim 1, characterized in that In step (2), the addition time is 10-30 min, and the addition temperature is 0-20 °C; the temperature for continued stirring and reaction is 5-15 °C, and the time for continued stirring and reaction is 10-30 min.

7. The preparation method of tert-butyl peroxyisobutyrate according to claim 1, characterized in that In step (3), the mass ratio of isobutyryl chloride to the liquid alkali in step (2) is 1:0.82-2.

06.

8. The preparation method of tert-butyl peroxyisobutyrate according to claim 1, characterized in that In step (3), the water-soluble distributor is one or two of tetramethylammonium chloride or methyltributylammonium chloride, and the mass ratio of isobutyryl chloride to the water-soluble distributor is 1:0.01-0.

03.

9. The preparation method of tert-butyl peroxyisobutyrate according to claim 1, characterized in that In step (3), the addition time is 10-30 min, and the addition temperature is 0-20 °C; the temperature for continued stirring and reaction is 5-20 °C, and the time for continued stirring and reaction is 10-120 min.

10. The preparation method of tert-butyl peroxyisobutyrate according to claim 1, wherein In step (4), the temperature for standing and layering is 0-15 °C, and the time for standing and layering is 20-30 min; the refining is to wash the crude product of tert-butyl peroxyisobutyrate with an alkali solution, an aqueous solution of sodium bicarbonate, and deionized water respectively.