A supported phosphotungstic acid catalyst, its preparation method and application

Abstract

This invention discloses a supported phosphotungstic acid catalyst, its preparation method, and its application. Specifically, distilled water and phosphotungstic acid are added to a reactor, stirring is started, mesoporous materials SBA-15, ZSM-5, or TiO2-SiO2 are added, stirring is continued, the catalyst is concentrated by vacuum distillation, and then dried to obtain the supported phosphotungstic acid catalyst. This catalyst is then applied to the preparation of sodium 5-dodecyloxycarbonylfuran-2-carboxylate. This invention produces fewer byproducts, has less corrosiveness to equipment, is simple to operate, has a short reaction time, is highly efficient, has a mild reaction, and is low in cost.

Description

Technical Field

[0001] This invention belongs to the field of chemical organic synthesis technology, specifically relating to a supported phosphotungstic acid catalyst, its preparation method, and its application. Background Technology

[0002] Currently, the sodium salt of 5-dodecyloxycarbonylfuran-2-carboxylic acid is widely studied and applied as a surfactant, possessing numerous advantages such as being a bio-based and renewable raw material. According to literature reports, sodium 5-dodecyloxycarbonylfuran-2-carboxylic acid is generally prepared by using 2,5-furandicarboxylic acid to prepare an acyl chloride with thionyl chloride to enhance its activity, followed by unilateral esterification with dodecyl alcohol, and then hydrolyzing it to form a salt. This method has a long synthetic route, high production costs, and the thionyl chloride used is highly corrosive to equipment, making experimental operations difficult and dangerous; therefore, it is not an ideal route for industrialization.

[0003] Therefore, it is an urgent problem to find a simple, safe, reliable, and low-cost method for synthesizing sodium 5-dodecanooxycarbonylfuran-2-carboxylate. This method requires a simple experimental route, mild reaction conditions, easy post-processing, and low cost. Summary of the Invention

[0004] To address the above problems, the present invention aims to provide a supported phosphotungstic acid catalyst, its preparation method, and its application.

[0005] To achieve the above objectives, the following technical solution is proposed:

[0006] A method for preparing a supported phosphotungstic acid catalyst includes the following steps:

[0007] 1) Add distilled water and phosphotungstic acid to the reactor and start stirring;

[0008] 2) Add mesoporous materials SBA-15, ZSM-5, or TiO2-SiO2 to the reactor and stir. ；

[0009] 3) Concentrate by vacuum distillation and dry to obtain a supported phosphotungstic acid catalyst.

[0010] Further, in step 2), the mixture is stirred at 75-85℃ for 0.5-24 hours.

[0011] Furthermore, the mass ratio of phosphotungstic acid to mesoporous material is 0.1-1:1-0.1.

[0012] A supported phosphotungstic acid catalyst prepared by the above preparation method.

[0013] The application of a supported phosphotungstic acid catalyst includes the following steps:

[0014] 1) Add solvent, 2,5-furandicarboxylic acid and supported phosphotungstic acid catalyst to the reaction vessel, start stirring, heat up, and remove water using a water separator;

[0015] 2) Add dodecyl alcohol, keep the reaction at a constant temperature, spread diatomaceous earth and filter while hot, collect the filtrate, concentrate the filtrate under reduced pressure to remove the organic phase, add n-heptane to the concentrated solid, stir and slurry, filter, collect the filter cake, wash it, transfer it to an oven and dry to obtain 5-dodecyloxycarbonylfuran-2-carboxylic acid.

[0016] 3) Dissolve the 5-dodecyloxycarbonylfuran-2-carboxylic acid from step 2) in tetrahydrofuran, turn on the stirrer, add the sodium source, stir, filter, and transfer the filter cake to an oven to dry to obtain sodium 5-dodecyloxycarbonylfuran-2-carboxylic acid.

[0017] Further, the solvent mentioned in step 1) is toluene, p-xylene, or tetrahydrofuran.

[0018] Further, in step 1), the mass ratio of the supported phosphotungstic acid catalyst to 2,5-furandicarboxylic acid is 0.05-1:1.

[0019] Further, in step 1), the temperature is raised to 65-110℃, and in step 2), dodecyl alcohol is added, and the reaction is maintained at this temperature for 0.5-24 hours.

[0020] Further, the sodium source mentioned in step 3) is sodium carbonate, sodium bicarbonate or sodium tert-butoxide, and the mixture is stirred for 0.5-24 hours.

[0021] The beneficial effects of this invention are as follows: This invention uses 2,5-furandicarboxylic acid as raw material, and obtains the product 5-dodecanooxycarbonylfuran-2-carboxylic acid by unilateral esterification catalyzed by a supported phosphotungstic acid catalyst. It produces fewer byproducts, has less corrosiveness to equipment, is simple to operate, requires a short reaction time, is highly efficient, has a mild reaction, and is low in cost. Attached Figure Description

[0022] Figure 1 The mass spectrum of sodium 5-dodecyloxycarbonylfuran-2-carboxylate prepared in Example 1;

[0023] Figure 2 The chromatogram is of sodium 5-dodecyloxycarbonylfuran-2-carboxylate prepared in Example 1. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited thereto.

[0025] Example 1

[0026] Preparation of supported phosphotungstic acid catalysts

[0027] 100.0 g of distilled water and 4.0 g of phosphotungstic acid were added to a 250 mL reaction flask. Stirring was started, and 4.0 g of mesoporous material SBA-15 was added. The temperature was raised to 85℃ and stirred for 2 hours. The reaction system was transferred to a single-necked flask and concentrated under reduced pressure at 85℃ until no obvious fractions were found. The solid was transferred to an oven and dried at 45℃ to obtain the supported phosphotungstic acid catalyst.

[0028] Synthesis of sodium 5-dodecyloxycarbonylfuran-2-carboxylate

[0029] The reaction process is as follows:

[0030]

[0031] 100.0 mL of toluene was added to a 250 mL reaction flask, and stirring was started. 10.0 g of 2,5-furandicarboxylic acid and 0.5 g of the supported phosphotungstic acid catalyst prepared above were added. The mixture was heated to 110 °C, and water was removed by reflux using a water separator. 12.0 g of dodecyl alcohol was added, and the mixture was kept at 110 °C for 6 hours. The reaction system was filtered while hot using diatomaceous earth, and the filtrate was collected. The filtrate was concentrated under reduced pressure until no obvious fractions were observed. 30.0 mL of n-heptane was added to the concentrated solid, and the mixture was stirred and slurried at 25 °C for 2 hours. The mixture was then filtered, and the filter cake was washed twice with 5.0 mL of n-heptane. The filter cake was transferred to an oven and dried at 45 °C to obtain a white solid, namely 5-dodecyloxycarbonylfuran-2-carboxylic acid.

[0032] 50.0 mL of tetrahydrofuran was added to 5-dodecyloxycarbonylfuran-2-carboxylic acid, and 6.16 g of sodium tert-butoxide was slowly added dropwise. The mixture was stirred for 1 h, filtered, and the filter cake was washed three times with 50 mL of tetrahydrofuran and then transferred to an oven at 60 °C for 12 h to obtain sodium 5-dodecyloxycarbonylfuran-2-carboxylic acid with a purity of 96.1%. The yield was 71%.

[0033] Its mass spectrum is as follows Figure 1 As shown, [M+Na]=347, indicating that the relative molecular weight is consistent with the target product. Figure 2 The image shows the chromatogram of sodium 5-dodecyloxycarbonylfuran-2-carboxylate, indicating that the purity of the obtained product is 96.1%.

[0034] Example 2

[0035] Preparation of supported phosphotungstic acid catalysts

[0036] 100.0 g of distilled water and 4.0 g of phosphotungstic acid were added to a 250 mL reaction flask. Stirring was started, and 4.0 g of mesoporous material ZSM-5 was added. The temperature was raised to 85℃ and stirred for 2 hours. The reaction system was transferred to a single-necked flask and concentrated under reduced pressure at 85℃ until no obvious fractions were found. The solid was transferred to an oven and dried at 45℃ to obtain the supported phosphotungstic acid catalyst.

[0037] Synthesis of sodium 5-dodecyloxycarbonylfuran-2-carboxylate

[0038] 100.0 mL of toluene was added to a 250 mL reaction flask, and stirring was started. 10.0 g of 2,5-furandicarboxylic acid and 0.5 g of the supported phosphotungstic acid catalyst prepared in Example 2 were added. The mixture was heated to 110 °C, and water was removed by reflux using a water separator. 12.0 g of dodecyl alcohol was added, and the mixture was kept at 110 °C for 6 hours. The reaction system was filtered while hot using diatomaceous earth, and the filtrate was collected. The filtrate was concentrated under reduced pressure until no obvious fractions were observed. 30.0 mL of n-heptane was added to the concentrated solid, and the mixture was stirred and slurried at 25 °C for 2 hours. The mixture was then filtered, and the filter cake was washed twice with 5.0 mL of n-heptane. The filter cake was transferred to an oven and dried at 45 °C to obtain a white solid, namely 5-dodecyloxycarbonylfuran-2-carboxylic acid.

[0039] 50.0 mL of tetrahydrofuran was added to 5-dodecyloxycarbonylfuran-2-carboxylic acid, and 6.16 g of sodium tert-butoxide was slowly added dropwise. The mixture was stirred for 1 h, filtered, and the filter cake was washed three times with 50 mL of tetrahydrofuran and then transferred to an oven at 60 °C for 12 h to obtain sodium 5-dodecyloxycarbonylfuran-2-carboxylic acid with a purity of 93.7%. The yield was 72%.

[0040] Example 3

[0041] Preparation of supported phosphotungstic acid catalysts

[0042] 100.0 g of distilled water and 4.0 g of phosphotungstic acid were added to a 250 mL reaction flask. Stirring was started, and 4.0 g of mesoporous material TiO2-SiO2 was added. The temperature was raised to 85℃ and stirred for 2 hours. The reaction system was transferred to a single-necked flask and concentrated under reduced pressure at 85℃ until no obvious fractions were found. The solid was transferred to an oven and dried at 45℃ to obtain the supported phosphotungstic acid catalyst.

[0043] Synthesis of sodium 5-dodecyloxycarbonylfuran-2-carboxylate

[0044] 100.0 mL of toluene was added to a 250 mL reaction flask, and stirring was started. 10.0 g of 2,5-furandicarboxylic acid and 0.5 g of the supported phosphotungstic acid catalyst prepared in Example 3 were added. The mixture was heated to 110 °C, and water was removed by reflux using a water separator. 12.0 g of dodecyl alcohol was added, and the mixture was kept at 110 °C for 6 hours. The reaction system was filtered while hot using diatomaceous earth, and the filtrate was collected. The filtrate was concentrated under reduced pressure until no obvious fractions were observed. 30.0 mL of n-heptane was added to the concentrated solid, and the mixture was stirred and slurried at 25 °C for 2 hours. The mixture was then filtered, and the filter cake was washed twice with 5.0 mL of n-heptane. The filter cake was transferred to an oven and dried at 45 °C to obtain a white solid, namely 5-dodecyloxycarbonylfuran-2-carboxylic acid.

[0045] 50.0 mL of tetrahydrofuran was added to 5-dodecyloxycarbonylfuran-2-carboxylic acid, and 6.16 g of sodium tert-butoxide was slowly added dropwise. The mixture was stirred for 1 h, filtered, and the filter cake was washed three times with 50 mL of tetrahydrofuran and then transferred to an oven at 60 °C for 12 h to obtain sodium 5-dodecyloxycarbonylfuran-2-carboxylic acid with a purity of 89.7%. The yield was 68%.

[0046] Example 4

[0047] Synthesis of sodium 5-dodecyloxycarbonylfuran-2-carboxylate

[0048] 100.0 mL of p-xylene was added to a 250 mL reaction flask, and stirring was started. 10.0 g of 2,5-furandicarboxylic acid and 0.5 g of the supported phosphotungstic acid catalyst prepared in Example 1 were added. The mixture was heated to 120 °C, and water was removed by reflux using a water separator. 12.0 g of dodecyl alcohol was added, and the mixture was kept at 120 °C for 6 hours. The reaction system was filtered while hot using diatomaceous earth, and the filtrate was collected. The filtrate was concentrated under reduced pressure until no obvious fractions were observed. 30.0 mL of n-heptane was added to the concentrated solid, and the mixture was stirred and slurried at 25 °C for 2 hours. The mixture was then filtered, and the filter cake was washed twice with 5.0 mL of n-heptane. The filter cake was transferred to an oven and dried at 45 °C to obtain a white solid, namely 5-dodecyloxycarbonylfuran-2-carboxylic acid.

[0049] 50.0 mL of tetrahydrofuran was added to 5-dodecyloxycarbonylfuran-2-carboxylic acid, and 6.16 g of sodium tert-butoxide was slowly added dropwise. The mixture was stirred for 1 h, filtered, and the filter cake was washed three times with 50 mL of tetrahydrofuran and then transferred to an oven at 60 °C for 12 h to obtain sodium 5-dodecyloxycarbonylfuran-2-carboxylic acid with a purity of 97.1%. The yield was 73%.

[0050] Example 5

[0051] Synthesis of sodium 5-dodecyloxycarbonylfuran-2-carboxylate

[0052] 100.0 mL of tetrahydrofuran was added to a 250 mL reaction flask, and stirring was started. 10.0 g of 2,5-furandicarboxylic acid and 0.5 g of the supported phosphotungstic acid catalyst prepared in Example 1 were added. The mixture was heated to 65 °C, and water was removed by reflux using a water separator. 12.0 g of dodecyl alcohol was added, and the mixture was kept at 65 °C for 6 hours. The reaction system was filtered while hot using diatomaceous earth, and the filtrate was collected. The filtrate was concentrated under reduced pressure until no obvious fractions were observed. 30.0 mL of n-heptane was added to the concentrated solid, and the mixture was stirred and slurried at 25 °C for 2 hours. The mixture was then filtered, and the filter cake was washed twice with 5.0 mL of n-heptane. The filter cake was transferred to an oven and dried at 45 °C to obtain a white solid, namely 5-dodecyloxycarbonylfuran-2-carboxylic acid.

[0053] 50.0 mL of tetrahydrofuran was added to 5-dodecyloxycarbonylfuran-2-carboxylic acid, and 6.16 g of sodium tert-butoxide was slowly added dropwise. The mixture was stirred for 1 h, filtered, and the filter cake was washed three times with 50 mL of tetrahydrofuran and then transferred to an oven at 60 °C for 12 h to obtain sodium 5-dodecyloxycarbonylfuran-2-carboxylic acid with a purity of 83.2%. The yield was 55%.

Claims

1. Use of a supported phosphotungstic acid catalyst, characterized in that Comprising the following steps: 1) adding solvent, 2,5-furan dicarboxylic acid and supported phosphotungstic acid catalyst into a reaction vessel, starting stirring, heating to 110℃, removing water by water trap; 2) adding dodecyl alcohol, keeping reaction, filtering by hot diatomite, collecting filtrate, removing organic phase by vacuum concentration, adding n-heptane into the concentrated solid, stirring and slurry, suction filtration, collecting and washing the filter cake, transferring to oven for drying to obtain 5-dodecyloxycarbonyl furan-2-carboxylic acid; 3) dissolving 5-dodecyloxycarbonyl furan-2-carboxylic acid in step 2) in tetrahydrofuran, starting stirring, adding sodium source, stirring, suction filtration, transferring the filter cake to oven for drying to obtain sodium 5-dodecyloxycarbonyl furan-2-carboxylate; The preparation method of the supported phosphotungstic acid catalyst comprises the following steps: 1) adding distilled water and phosphotungstic acid into a reactor, starting stirring; 2) Mesoporous material SBA-15, ZSM-5 or TiO2-SiO2 was added to the reactor and stirred at 75-85 °C for 0.5-24 h ； 3) concentrating by vacuum distillation, drying to obtain the supported phosphotungstic acid catalyst; The mass ratio of phosphotungstic acid to mesoporous material is 0.1-1:1-0.

1.

2. Use according to claim 1, wherein The solvent in step 1) in the application step is toluene, p-xylene or tetrahydrofuran.

3. The use according to claim 1, wherein The mass ratio of the supported phosphotungstic acid catalyst to 2,5-furan dicarboxylic acid in step 1) in the application step is 0.05-1:

1.

4. The use according to claim 1, wherein The dodecyl alcohol in step 2) in the application step is reacted for 0.5-24 hours.

5. The use according to claim 1, wherein The sodium source in step 3) in the application step is sodium carbonate, sodium bicarbonate or sodium tert-butoxide, and stirring is performed for 0.5-24 hours.

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