Solid acid catalyst for synthesizing 4-methyl-2,6-di-tert-butylphenol, its preparation method and application

Abstract

The application discloses a solid acid catalyst for synthesizing 4-methyl-2,6-di-tert-butyl phenol and a preparation method and application thereof. The catalyst is prepared by taking one or more of SiO2, TiO2 and MCM-41 molecular sieve as a starting carrier, and then being modified by Ba and acid, modified by organic zirconium and crosslinked by trifluoromethanesulfonic acid. The catalyst is applied to the production of 4-methyl-2,6-di-tert-butyl phenol from p-methyl phenol and isobutene, and has the advantages of mild reaction condition, short reaction time, high raw material conversion rate, high product selectivity, long catalyst service life and simple use process. The conversion rate of p-methyl phenol can reach 100%, and the selectivity of 4-methyl-2,6-di-tert-butyl phenol is between 60% and 81.5%.

Description

Technical Field

[0001] This invention belongs to the field of catalysis technology, specifically relating to a solid acid catalyst for catalyzing the synthesis of 4-methyl-2,6-di-tert-butylphenol from p-methylphenol and isobutylene. Background Technology

[0002] 4-Methyl-2,6-di-tert-butylphenol (BHT) is an important hindered phenolic antioxidant, widely used in food processing, oil and fat preservation, fuel oil preservation, as well as food and medical product packaging materials, polyolefins, synthetic rubber, plastics and other fields.

[0003] In recent years, the demand for BHT has been increasing year by year, and the market supply cannot meet the demand. Researchers from various countries have conducted in-depth research on the catalytic synthesis of BHT, and the main catalysts used include liquid acids, metal oxides, metal salts, ion exchange resins, solid superacids, and heteropolyacids. Liquid acids such as sulfuric acid, sulfur trioxide, sulfosalicylic acid, and benzenesulfonic acid are currently the main catalysts used by domestic production companies. These catalysts have the advantages of low dosage, low cost and easy availability, high feed conversion, and good selectivity. However, they also have many problems, such as the need for further separation between the catalyst and the product (or feedstock), resulting in high production costs; the strong corrosiveness of the catalyst, resulting in large equipment investment; the waste acid treatment process generates a large amount of solid waste that pollutes the environment; and the small amount of acid remaining in the crude product can cause dehydrocarbonization reactions during the distillation separation process, resulting in poor product quality, which greatly limits its application.

[0004] Metal salt catalysts such as ZrCl4, AlCl3, FeCl3, and TiCl4 were the first solid acid catalysts used in the synthesis of BHT. Although the conversion rate of raw materials is high, the strong acidity leads to a large number of by-products. At the same time, there are problems such as post-processing similar to those of liquid acids, which makes it difficult to apply them industrially.

[0005] Boisselet L. (J. Chem. Res. 1958, 856-857) et al. used treated sulfonic acid strong acid cation exchange resin as a catalyst, and reacted p-methylphenol and isobutylene in a 1:3 molar ratio in a batch reactor at 60°C with stirring. After complete reaction, BHT was obtained in a yield of 26%. Although resin catalysts have the advantage of fewer by-products, they have problems such as poor heat resistance, uneven pore distribution, short lifespan, and poor strength. Further improvements are needed for their application in industrial production. Ganapati DY (Ind. Eng. Chem. Res. 1996, 35:721-731) et al. used SO4 2-ZrO2 was used as a catalyst to catalyze the synthesis of BHT from p-methylphenol and isobutylene. Its catalytic activity and product selectivity were higher than those of H2SO4. Although solid superacids possess strong acidity and catalytic activity, their poor activity stability, short lifespan, poor heat resistance, low strength, and difficulty in preparation make them unsuitable for industrial production. Bi ju M. Devassy (J. Mol. Cat. A: Chem. 2004, 210: 125-130) et al. supported phosphotungstic acid on a zirconium dioxide support to prepare a heteropolyacid catalyst, which was applied to the alkylation reaction of p-methylphenol and tert-butanol. The reaction was carried out at a temperature of 130℃, a phenol-to-alcohol molar ratio of 1:3, and a space velocity of 4 h⁻¹. -1 With a phosphotungstic acid loading of 15 wt%, the conversion rate of p-methylphenol reached 61.0%, the selectivity of 2-tert-butyl-p-methylphenol reached 81.4%, and the selectivity of 4-methyl-2,6-di-tert-butylphenol was 18.1%. Although heteropolyacid catalysts have good alkylation catalytic activity and selectivity, and have the advantages of low corrosivity and volatility, their small specific surface area, high price, poor activity stability, short lifespan, and difficulty in preparation mean they cannot yet meet the requirements of industrial production.

[0006] Gulf Industries in the United States used SiO2·Al2O3 as the main catalyst, with zirconium oxide, titanium oxide, magnesium oxide, etc. as auxiliary agents, in a fixed-bed continuous reactor with a space velocity of 0.5–2 h⁻¹. -1 The reaction temperature was 122–178℃, the raw material conversion rate was 8%, and the target product selectivity was 19%. However, the catalytic activity was low, and deactivation was rapid, making it unsuitable for industrial application. Li Wenfeng et al. (Tianjin University, 2006, Master's Thesis) modified Hβ zeolite with metal cations, achieving a p-methylphenol conversion rate of 70.2% and a 2-tert-butyl-p-methylphenol selectivity of 93.6%, but the BHT yield was only about 3%, making industrial application difficult. Luo Xiaolin et al. (CN107649170, CN201710913156) disclosed a molecular sieve-based solid acid catalyst with a p-methylphenol conversion rate of 65.8% and a BHT selectivity of 36.8%. Although this reached the level of a catalyst suitable for industrial application, the p-methylphenol conversion rate was low, and the activity was still far from that of liquid acids. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the catalysts used in the above-mentioned synthesis of BHT and to provide a solid acid catalyst for the synthesis of BHT from p-methylphenol and isobutylene. This catalyst has the characteristics of high p-methylphenol conversion, good BHT selectivity, and long service life.

[0008] The solid acid catalyst provided by this invention is prepared by the following method:

[0009] Step 1: Add BaCl2 to deionized water and add the support. Stir at room temperature for 0.5-2 hours, then add a 30% (w / w) H2SO4 aqueous solution. Stir at room temperature for 1-3 hours, filter, wash, and dry at 80-100℃ for 6-10 hours to obtain the modified support. The support is selected from one or more of SiO2, TiO2, and MCM-41 molecular sieves. The mass ratio of BaCl2 to the support is 1:100-200, and the molar ratio of BaCl2 to H2SO4 is 1:1.2-2.

[0010] Step 2: Add 2-aminoterephthalic acid to organic solvent A, stir to dissolve, then add ZrCl4 and glacial acetic acid, stir for 1-3 hours, then add the modified support, continue stirring for 1-3 hours, then transfer to a reaction vessel, heat to 100-170℃, maintain the temperature for 20-48 hours, cool and filter to obtain organozirconium modified support; wherein, the molar ratio of 2-aminoterephthalic acid to ZrCl4 and glacial acetic acid is 1:0.8-3:1-2, and the mass ratio of 2-aminoterephthalic acid to modified support is 1:0.5-2.

[0011] Step 3: Disperse 1,4-butyryl lactone in organic solvent B, stir evenly, add organozirconium modified carrier, react at 100-140℃ for 18-24h, cool, filter, wash, and dry at 130-160℃ for 12-24h to obtain sulfonic acid modified carrier; wherein, the mass ratio of 1,4-butyryl lactone to organozirconium modified carrier is 1:0.8-3.

[0012] Step 4: Add the sulfonic acid modified support to organic solvent C, stir evenly, and then add trifluoromethanesulfonic acid dropwise in an ice bath at -20 to 0°C. After the addition is complete, continue stirring for 1 to 3 hours, filter, wash, and dry at 80 to 120°C for 6 to 10 hours to prepare a solid acid catalyst; wherein the mass ratio of trifluoromethanesulfonic acid to sulfonic acid modified support is 1:10 to 30.

[0013] Furthermore, in step 1 above, the mass ratio of BaCl2 to deionized water is 1:20 to 100.

[0014] Furthermore, in step 2 above, the mass ratio of 2-aminoterephthalic acid to organic solvent A is 1:200-400, and organic solvent A is one or two of N,N-dimethylformamide, dimethyl sulfoxide, and toluene.

[0015] Furthermore, in step 3 above, the mass ratio of 1,4-butyryl lactone to organic solvent B is 1:100 to 400, and the organic solvent B is one or more of o-xylene, m-xylene, p-xylene, and ethylbenzene.

[0016] Furthermore, in step 4 above, the mass ratio of the sulfonic acid modified carrier to the organic solvent C is 1:100-300, and the organic solvent C is one or more of dichloromethane, trichloromethane, and tetrachloromethane.

[0017] The present invention also provides the use of the solid acid catalyst in the catalytic synthesis of 4-methyl-2,6-di-tert-butylphenol from p-methylphenol and isobutylene. The specific method is as follows: p-methylphenol and isobutylene are reacted at a molar ratio of 1:3 to 5 at 60 to 80°C for 4 to 8 hours under the action of a solid acid catalyst, wherein the amount of solid acid catalyst added is 10% to 50% of the mass of p-methylphenol, to obtain 4-methyl-2,6-di-tert-butylphenol.

[0018] The beneficial effects of this invention are as follows:

[0019] The catalyst of this invention, after being modified with barium, has increased density, is easier to separate, and reduces separation costs. After the catalytic reaction, it has a high single-pass conversion rate of p-methylphenol, high selectivity for the target product BHT, and a significantly increased single-pass yield of BHT. The catalyst activity is close to that of liquid acid catalysts, which greatly reduces production costs. Detailed Implementation

[0020] The present invention will be further described in detail below with reference to the embodiments, but the scope of protection of the present invention is not limited to these embodiments.

[0021] Example 1

[0022] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add TiO2 and stir at room temperature for 1 hour. Then add a 30% H2SO4 aqueous solution and stir at room temperature for 1 hour. Filter, wash, and dry in an oven at 80℃ for 10 hours to obtain modified TiO2. The mass ratio of BaCl2 to deionized water is 1:20, the mass ratio of BaCl2 to the carrier is 1:100, and the molar ratio of BaCl2 to H2SO4 is 1:1.2.

[0023] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to toluene. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 3 hours. Then add modified TiO2 and continue stirring for 2 hours. Transfer the mixture to a reaction vessel, heat it to 170℃ at 3℃ / min, maintain the temperature for 35 hours, cool, and filter to obtain organozirconium-modified TiO2. The mass ratio of 2-aminoterephthalic acid to toluene is 1:250, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:2:2, and the mass ratio of 2-aminoterephthalic acid to modified TiO2 is 1:1.

[0024] Step 3: Weigh 0.1 g of 1,4-butyric acid lactone and disperse it in o-xylene. After stirring evenly, add organozirconium-modified TiO2 and react at 100℃ for 24 h. Then cool, filter, wash, and dry in an oven at 130℃ for 20 h to obtain sulfonic acid-modified TiO2. The mass ratio of 1,4-butyric acid lactone to o-xylene is 1:100, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified TiO2 is 1:0.8.

[0025] Step 4: Weigh 0.1g of sulfonic acid-modified TiO2 and add it to dichloromethane. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at -10℃. After the addition is complete, continue stirring for 3 hours. Filter, wash, and dry in an oven at 120℃ for 6 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified TiO2 to dichloromethane is 1:300, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified TiO2 is 1:30.

[0026] Example 2

[0027] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add SiO2 and stir at room temperature for 2 hours. Then add a 30% H2SO4 aqueous solution and stir at room temperature for 2 hours. Filter, wash, and dry in an oven at 100℃ for 6 hours to obtain modified SiO2. The mass ratio of BaCl2 to deionized water is 1:100, the mass ratio of BaCl2 to SiO2 is 1:200, and the molar ratio of BaCl2 to H2SO4 is 1:2.

[0028] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to dimethyl sulfoxide. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 3 hours. Then add modified SiO2 and continue stirring for 2 hours. Transfer the mixture to a reaction vessel, heat it to 170℃ at 3℃ / min, maintain the temperature for 35 hours, cool, and filter to obtain organozirconium-modified SiO2. The mass ratio of 2-aminoterephthalic acid to dimethyl sulfoxide is 1:250, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:2:2, and the mass ratio of 2-aminoterephthalic acid to modified SiO2 is 1:1.

[0029] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in m-xylene. After stirring evenly, add organozirconium-modified SiO2 and react at 120℃ for 20h. Then cool, filter, wash, and dry in an oven at 160℃ for 12h to obtain sulfonic acid-modified SiO2. The mass ratio of 1,4-butyric acid lactone to m-xylene is 1:300, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified SiO2 is 1:3.

[0030] Step 4: Weigh 0.1g of sulfonic acid-modified SiO2 and add it to dichloromethane. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at -20℃. After the addition is complete, continue stirring for 2 hours. Filter, wash, and dry in an oven at 100℃ for 8 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified SiO2 to dichloromethane is 1:200, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified SiO2 is 1:20.

[0031] Example 3

[0032] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add MCM-41 and stir at room temperature for 2 hours. Then add a 30% H2SO4 aqueous solution and stir at room temperature for 2 hours. Filter, wash, and dry in an oven at 100℃ for 6 hours to obtain modified MCM-41. The mass ratio of BaCl2 to deionized water is 1:20, the mass ratio of BaCl2 to MCM-41 is 1:100, and the molar ratio of BaCl2 to H2SO4 is 1:2.

[0033] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to toluene. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 1 hour. Then add modified MCM-41 and continue stirring for 1 hour. Transfer the mixture to a reaction vessel, heat it to 100℃ at 2℃ / min, maintain the temperature for 40 hours, cool, and filter to obtain organozirconium-modified MCM-41. The mass ratio of 2-aminoterephthalic acid to toluene is 1:200, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:0.8:1, and the mass ratio of 2-aminoterephthalic acid to modified MCM-41 is 1:0.5.

[0034] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in m-xylene. After stirring evenly, add organozirconium-modified MCM-41 and react at 140℃ for 18h. Then cool, filter, wash, and dry in an oven at 150℃ for 18h to obtain sulfonic acid-modified MCM-41. The mass ratio of 1,4-butyric acid lactone to m-xylene is 1:200, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified MCM-41 is 1:1.2.

[0035] Step 4: Weigh 0.1g of sulfonic acid-modified MCM-41 and add it to chloroform. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at -5℃. After the addition is complete, continue stirring for 3 hours. Filter, wash, and dry in an oven at 120℃ for 3 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified MCM-41 to chloroform is 1:140, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified MCM-41 is 1:10.

[0036] Example 4

[0037] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add SiO2 and stir at room temperature for 1.5h. Then add 30% H2SO4 aqueous solution and stir at room temperature for 3h. Filter, wash, and dry in an oven at 90℃ for 8h to obtain modified SiO2. The mass ratio of BaCl2 to deionized water is 1:60, the mass ratio of BaCl2 to SiO2 is 1:160, and the molar ratio of BaCl2 to H2SO4 is 1:1.8.

[0038] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to dimethyl sulfoxide. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 2 hours. Then add modified SiO2 and continue stirring for 2 hours. Transfer the mixture to a reaction vessel, heat it to 150℃ at 4℃ / min, maintain the temperature for 30 hours, cool, and filter to obtain organozirconium-modified SiO2. The mass ratio of 2-aminoterephthalic acid to dimethyl sulfoxide is 1:400, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:3:2, and the mass ratio of 2-aminoterephthalic acid to modified SiO2 is 1:1.5.

[0039] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in ethylbenzene. After stirring evenly, add organozirconium-modified SiO2 and react at 140℃ for 18h. Then cool, filter, wash, and dry in an oven at 150℃ for 18h to obtain sulfonic acid-modified SiO2. The mass ratio of 1,4-butyric acid lactone to ethylbenzene is 1:200, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified SiO2 is 1:1.2.

[0040] Step 4: Weigh 0.1g of sulfonic acid-modified SiO2 and add it to tetrachloromethane. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at -20℃. After the addition is complete, continue stirring for 2 hours. Filter, wash, and dry in an oven at 100℃ for 8 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified SiO2 to tetrachloromethane is 1:200, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified SiO2 is 1:20.

[0041] Example 5

[0042] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add TiO2 and stir at room temperature for 1 hour. Then add a 30% (w / w) H2SO4 aqueous solution and stir at room temperature for 1 hour. Filter, wash, and dry in an oven at 100℃ for 8 hours to obtain modified TiO2. The mass ratio of BaCl2 to deionized water is 1:100, the mass ratio of BaCl2 to TiO2 is 1:200, and the molar ratio of BaCl2 to H2SO4 is 1:1.5.

[0043] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to toluene. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 2 hours. Then add modified TiO2 and continue stirring for 2 hours. Transfer the mixture to a reaction vessel, heat it to 130℃ at 2℃ / min, and hold it at that temperature for 32 hours. After cooling and filtering, obtain organozirconium-modified TiO2. The mass ratio of 2-aminoterephthalic acid to toluene is 1:300, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:2:1, and the mass ratio of 2-aminoterephthalic acid to modified TiO2 is 1:1.

[0044] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in ethylbenzene. After stirring evenly, add organozirconium-modified TiO2 and react at 120℃ for 20h. Then cool, filter, wash, and dry in an oven at 160℃ for 12h to obtain sulfonic acid-modified TiO2. The mass ratio of 1,4-butyric acid lactone to ethylbenzene is 1:300, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified TiO2 is 1:3.

[0045] Step 4: Weigh 0.1g of sulfonic acid-modified TiO2 and add it to tetrachloromethane. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at -10℃. After the addition is complete, continue stirring for 3 hours. Filter, wash, and dry in an oven at 120℃ for 6 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified TiO2 to tetrachloromethane is 1:300, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified TiO2 is 1:30.

[0046] Example 6

[0047] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add MCM-41 and stir at room temperature for 1.5h. Then add 30% H2SO4 aqueous solution and stir at room temperature for 3h. Filter, wash, and dry in an oven at 90℃ for 8h to obtain modified MCM-41. The mass ratio of BaCl2 to deionized water is 1:60, the mass ratio of BaCl2 to MCM-41 is 1:160, and the molar ratio of BaCl2 to H2SO4 is 1:1.8.

[0048] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to N,N-dimethylformamide. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 1 hour. Then add modified MCM-41 and continue stirring for 1 hour. Transfer the mixture to a reaction vessel, heat it to 100℃ at 2℃ / min, maintain the temperature for 40 hours, cool, and filter to obtain organozirconium-modified MCM-41. The mass ratio of 2-aminoterephthalic acid to N,N-dimethylformamide is 1:200, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:0.8:1, and the mass ratio of 2-aminoterephthalic acid to modified MCM-41 is 1:0.5.

[0049] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in ethylbenzene. After stirring evenly, add organozirconium-modified MCM-41 and react at 100℃ for 24h. Then cool, filter, wash, and dry in an oven at 130℃ for 20h to obtain sulfonic acid-modified MCM-41. The mass ratio of 1,4-butyric acid lactone to ethylbenzene is 1:100, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified MCM-41 is 1:0.8.

[0050] Step 4: Weigh 0.1g of sulfonic acid-modified MCM-41 and add it to dichloromethane. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at 0℃. After the addition is complete, continue stirring for 1 hour. Filter, wash, and dry in an oven at 80℃ for 10 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified MCM-41 to dichloromethane is 1:100, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified MCM-41 is 1:10.

[0051] Example 7

[0052] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add MCM-41 and stir at room temperature for 1 hour. Then add a 30% H2SO4 aqueous solution and stir at room temperature for 1 hour. Filter, wash, and dry in an oven at 100℃ for 8 hours to obtain modified MCM-41. The mass ratio of BaCl2 to deionized water is 1:100, the mass ratio of BaCl2 to MCM-41 is 1:200, and the molar ratio of BaCl2 to H2SO4 is 1:1.5.

[0053] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to toluene. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 2 hours. Then add modified MCM-41 and continue stirring for 2 hours. Transfer the mixture to a reaction vessel, heat it to 150℃ at 4℃ / min, maintain the temperature for 30 hours, cool, and filter to obtain organozirconium-modified MCM-41. The mass ratio of 2-aminoterephthalic acid to toluene is 1:400, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:3:2, and the mass ratio of 2-aminoterephthalic acid to modified MCM-41 is 1:1.5.

[0054] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in o-xylene. After stirring evenly, add organozirconium-modified MCM-41 and react at 120℃ for 20h. Then cool, filter, wash, and dry in an oven at 160℃ for 12h to obtain sulfonic acid-modified MCM-41. The mass ratio of 1,4-butyric acid lactone to o-xylene is 1:300, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified MCM-41 is 1:3.

[0055] Step 4: Weigh 0.1g of sulfonic acid-modified MCM-41 and add it to chloroform. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at 0℃. After the addition is complete, continue stirring for 1 hour. Filter, wash, and dry in an oven at 80℃ for 10 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified MCM-41 to chloroform is 1:100, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified MCM-41 is 1:10.

[0056] Example 8

[0057] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add TiO2 and stir at room temperature for 2 hours. Then add a 30% H2SO4 aqueous solution and stir at room temperature for 2 hours. Filter, wash, and dry in an oven at 100℃ for 6 hours to obtain modified TiO2. The mass ratio of BaCl2 to deionized water is 1:100, the mass ratio of BaCl2 to TiO2 is 1:200, and the molar ratio of BaCl2 to H2SO4 is 1:2.

[0058] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to dimethyl sulfoxide. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 2 hours. Then add modified TiO2 and continue stirring for 2 hours. Transfer the mixture to a reaction vessel, heat it to 130℃ at 2℃ / min, maintain the temperature for 32 hours, cool, and filter to obtain organozirconium-modified TiO2. The mass ratio of 2-aminoterephthalic acid to dimethyl sulfoxide is 1:300, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:2:1, and the mass ratio of 2-aminoterephthalic acid to modified TiO2 is 1:1.

[0059] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in m-xylene. After stirring evenly, add organozirconium-modified TiO2 and react at 100℃ for 24h. Then cool, filter, wash, and dry in an oven at 130℃ for 20h to obtain sulfonic acid-modified TiO2. The mass ratio of 1,4-butyric acid lactone to m-xylene is 1:100, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified TiO2 is 1:0.8.

[0060] Step 4: Weigh 0.1g of sulfonic acid-modified TiO2 and add it to chloroform. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at -10℃. After the addition is complete, continue stirring for 3 hours. Filter, wash, and dry in an oven at 120℃ for 6 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified TiO2 to chloroform is 1:300, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified TiO2 is 1:30.

[0061] Example 9

[0062] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add SiO2 and stir at room temperature for 1 hour. Then add a 30% H2SO4 aqueous solution and stir at room temperature for 1 hour. Filter, wash, and dry in an oven at 80℃ for 10 hours to obtain modified SiO2. The mass ratio of BaCl2 to deionized water is 1:20, the mass ratio of BaCl2 to SiO2 is 1:100, and the molar ratio of BaCl2 to H2SO4 is 1:1.2.

[0063] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to dimethyl sulfoxide. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 1 hour. Then add modified SiO2 and continue stirring for 1 hour. Transfer the mixture to a reaction vessel, heat it to 100℃ at 2℃ / min, maintain the temperature for 40 hours, cool, and filter to obtain organozirconium-modified SiO2. The mass ratio of 2-aminoterephthalic acid to dimethyl sulfoxide is 1:200, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:0.8:1, and the mass ratio of 2-aminoterephthalic acid to modified SiO2 is 1:0.5.

[0064] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in p-xylene. After stirring evenly, add organozirconium-modified SiO2 and react at 120℃ for 20h. Then cool, filter, wash, and dry in an oven at 160℃ for 12h to obtain sulfonic acid-modified SiO2. The mass ratio of 1,4-butyric acid lactone to p-xylene is 1:300, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified SiO2 is 1:3.

[0065] Step 4: Weigh 0.1g of sulfonic acid-modified SiO2 and add it to chloroform. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at -20℃. After the addition is complete, continue stirring for 2 hours. Filter, wash, and dry in an oven at 100℃ for 8 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified SiO2 to chloroform is 1:200, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified SiO2 is 1:20.

[0066] Example 10

[0067] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add TiO2 and stir at room temperature for 1.5h. Then add 30% H2SO4 aqueous solution and stir at room temperature for 3h. Filter, wash, and dry in an oven at 90℃ for 8h to obtain modified TiO2. The mass ratio of BaCl2 to deionized water is 1:60, the mass ratio of BaCl2 to TiO2 is 1:160, and the molar ratio of BaCl2 to H2SO4 is 1:1.8.

[0068] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to N,N-dimethylformamide. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 3 hours. Then add modified TiO2 and continue stirring for 2 hours. Transfer the mixture to a reaction vessel, heat it to 170℃ at 3℃ / min, maintain the temperature for 35 hours, cool, and filter to obtain organozirconium-modified TiO2. The mass ratio of 2-aminoterephthalic acid to N,N-dimethylformamide is 1:250, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:2:2, and the mass ratio of 2-aminoterephthalic acid to modified TiO2 is 1:1.

[0069] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in o-xylene. After stirring evenly, add organozirconium-modified TiO2 and react at 140℃ for 18h. Then cool, filter, wash, and dry in an oven at 150℃ for 18h to obtain sulfonic acid-modified TiO2. The mass ratio of 1,4-butyric acid lactone to o-xylene is 1:200, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified TiO2 is 1:1.2.

[0070] Step 4: Weigh 0.1g of sulfonic acid-modified TiO2 and add it to dichloromethane. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at -5℃. After the addition is complete, continue stirring for 3 hours. Filter, wash, and dry in an oven at 120℃ for 10 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified TiO2 to dichloromethane is 1:140, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified TiO2 is 1:10.

[0071] Example 11

[0072] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add SiO2 and stir at room temperature for 1 hour. Then add a 30% H2SO4 aqueous solution and stir at room temperature for 1 hour. Filter, wash, and dry in an oven at 100℃ for 8 hours to obtain modified SiO2. The mass ratio of BaCl2 to deionized water is 1:100, the mass ratio of BaCl2 to SiO2 is 1:200, and the molar ratio of BaCl2 to H2SO4 is 1:1.5.

[0073] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to N,N-dimethylformamide. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 3 hours. Then add modified SiO2 and continue stirring for 3 hours. Transfer the mixture to a reaction vessel, heat it to 150℃ at 4℃ / min, maintain the temperature for 30 hours, cool, and filter to obtain organozirconium-modified SiO2. The mass ratio of 2-aminoterephthalic acid to N,N-dimethylformamide is 1:400, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:3:2, and the mass ratio of 2-aminoterephthalic acid to modified SiO2 is 1:1.5.

[0074] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in p-xylene. After stirring evenly, add organozirconium-modified SiO2 and react at 100℃ for 24h. Then cool, filter, wash, and dry in an oven at 130℃ for 20h to obtain sulfonic acid-modified SiO2. The mass ratio of 1,4-butyric acid lactone to p-xylene is 1:100, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified SiO2 is 1:0.8.

[0075] Step 4: Weigh 0.1g of sulfonic acid-modified SiO2 and add it to tetrachloromethane. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at 0℃. After the addition is complete, continue stirring for 1 hour. Filter, wash, and dry in an oven at 80℃ for 10 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified SiO2 to tetrachloromethane is 1:100, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified SiO2 is 1:30.

[0076] Example 12

[0077] Step 1: Weigh 0.1g BaCl2 and add it to deionized water, then add MCM-41 and stir at room temperature for 1 hour. Then add a 30% H2SO4 aqueous solution and stir at room temperature for 1 hour. Filter, wash, and dry in an oven at 80℃ for 10 hours to obtain modified MCM-41. The mass ratio of BaCl2 to deionized water is 1:20, the mass ratio of BaCl2 to MCM-41 is 1:100, and the molar ratio of BaCl2 to H2SO4 is 1:1.2.

[0078] Step 2: Weigh 0.1g of 2-aminoterephthalic acid and add it to N,N-dimethylformamide. After stirring and dissolving, add ZrCl4 and glacial acetic acid, and stir for 2 hours. Then add modified MCM-41 and continue stirring for 2 hours. Transfer the mixture to a reaction vessel, heat it to 130℃ at 2℃ / min, maintain the temperature for 32 hours, cool, and filter to obtain organozirconium-modified MCM-41. The mass ratio of 2-aminoterephthalic acid to N,N-dimethylformamide is 1:300, the molar ratio of 2-aminoterephthalic acid, ZrCl4, and glacial acetic acid is 1:2:1, and the mass ratio of 2-aminoterephthalic acid to modified MCM-41 is 1:1.

[0079] Step 3: Weigh 0.1g of 1,4-butyric acid lactone and disperse it in p-xylene. After stirring evenly, add organozirconium-modified MCM-41 and react at 140℃ for 18h. Then cool, filter, wash, and dry in an oven at 150℃ for 18h to obtain sulfonic acid-modified MCM-41. The mass ratio of 1,4-butyric acid lactone to p-xylene is 1:200, and the mass ratio of 1,4-butyric acid lactone to organozirconium-modified MCM-41 is 1:1.2.

[0080] Step 4: Weigh 0.1g of sulfonic acid-modified MCM-41 and add it to tetrachloromethane. After stirring evenly, add trifluoromethanesulfonic acid dropwise in an ice bath at -5℃. After the addition is complete, continue stirring for 3 hours. Filter, wash, and dry in an oven at 120℃ for 3 hours to prepare a solid acid catalyst. The mass ratio of sulfonic acid-modified MCM-41 to tetrachloromethane is 1:140, and the mass ratio of trifluoromethanesulfonic acid to sulfonic acid-modified MCM-41 is 1:20.

[0081] Example 13

[0082] The solid acid catalysts prepared in Examples 1-12 above were used to catalyze the synthesis of 4-methyl-2,6-di-tert-butylphenol from p-methylphenol and isobutylene. Specific experiments were conducted as follows:

[0083] 108.14 g (1 mol) of p-methylphenol, 224.44 g (4 mol) of isobutylene and 32.44 g of solid acid catalyst were added to the reactor and stirred at 80 °C for 6 hours. The reaction results are shown in Table 1.

[0084] Table 1. Catalytic reaction results of the catalyst of the present invention

[0085]

[0086]

[0087] Further, taking the catalyst of Example 6 as an example, the catalyst life was tested. After 40 uses, the conversion rate of p-methylphenol was 100%, and the selectivity of 4-methyl-2,6-di-tert-butylphenol still reached 61%.

Claims

1. A method for preparing a solid acid catalyst for the synthesis of 4-methyl-2,6-di-tert-butylphenol, characterized in that, The preparation method includes the following steps: Step 1: Add BaCl2 to deionized water and add the support. Stir at room temperature for 0.5-2 hours, then add a 30% (w / w) H2SO4 aqueous solution. Stir at room temperature for 1-3 hours, filter, wash, and dry at 80-100℃ for 6-10 hours to obtain the modified support. The support is selected from one or more of SiO2, TiO2, and MCM-41 molecular sieves. The mass ratio of BaCl2 to the support is 1:100-200, and the molar ratio of BaCl2 to H2SO4 is 1:1.2-2. Step 2: Add 2-aminoterephthalic acid to organic solvent A, stir to dissolve, then add ZrCl4 and glacial acetic acid, stir for 1-3 hours, then add the modified support, continue stirring for 1-3 hours, then transfer to a reaction vessel, heat to 100-170℃, maintain the temperature for 20-48 hours, cool and filter to obtain organozirconium modified support; wherein, the molar ratio of 2-aminoterephthalic acid to ZrCl4 and glacial acetic acid is 1:0.8-3:1-2, and the mass ratio of 2-aminoterephthalic acid to modified support is 1:0.5-2; Step 3: Disperse 1,4-butyryl lactone in organic solvent B, stir evenly, add organozirconium modified support, react at 100-140℃ for 18-24h, cool, filter, wash, and dry at 130-160℃ for 12-24h to obtain sulfonic acid modified support; wherein, the mass ratio of 1,4-butyryl lactone to organozirconium modified support is 1:0.8-3; Step 4: Add the sulfonic acid modified support to organic solvent C, stir evenly, and then add trifluoromethanesulfonic acid dropwise in an ice bath at -20 to 0°C. After the addition is complete, continue stirring for 1 to 3 hours, filter, wash, and dry at 80 to 120°C for 6 to 10 hours to prepare a solid acid catalyst; wherein the mass ratio of trifluoromethanesulfonic acid to sulfonic acid modified support is 1:10 to 30.

2. The method for preparing the solid acid catalyst for the synthesis of 4-methyl-2,6-di-tert-butylphenol according to claim 1, characterized in that, In step 1, the mass ratio of BaCl2 to deionized water is 1:20 to 100.

3. The method for preparing the solid acid catalyst for the synthesis of 4-methyl-2,6-di-tert-butylphenol according to claim 1, characterized in that, In step 2, the mass ratio of 2-aminoterephthalic acid to organic solvent A is 1:200-400, and organic solvent A is one or two of N,N-dimethylformamide, dimethyl sulfoxide, and toluene.

4. The method for preparing the solid acid catalyst for the synthesis of 4-methyl-2,6-di-tert-butylphenol according to claim 1, characterized in that, In step 3, the mass ratio of 1,4-butyryl lactone to organic solvent B is 1:100-400, and the organic solvent B is one or more of o-xylene, m-xylene, p-xylene, and ethylbenzene.

5. The method for preparing the solid acid catalyst for the synthesis of 4-methyl-2,6-di-tert-butylphenol according to claim 1, characterized in that, In step 4, the mass ratio of the sulfonic acid modified carrier to the organic solvent C is 1:100-300, and the organic solvent C is one or more of dichloromethane, trichloromethane, and tetrachloromethane.

6. The solid acid catalyst obtained by any one of the preparation methods of claims 1 to 5.

7. Use of the solid acid catalyst according to claim 6 in the catalytic synthesis of 4-methyl-2,6-di-tert-butylphenol from p-methylphenol and isobutylene.

8. The use of the solid acid catalyst according to claim 7 in the catalytic synthesis of 4-methyl-2,6-di-tert-butylphenol from p-methylphenol and isobutylene, characterized in that, p-Cresol and isobutylene were reacted at a molar ratio of 1:3 to 5 at 60 to 80 °C for 4 to 8 hours under the action of a solid acid catalyst, wherein the amount of solid acid catalyst added was 10% to 50% of the mass of p-cresol, to obtain 4-methyl-2,6-di-tert-butylphenol.

Images