A metal-organic framework porous polymer material, its preparation method and application

Abstract

The present invention relates to the technical field of trimethylolethane preparation, and specifically discloses a metal-organic framework porous polymer material, a preparation method thereof and an application. The preparation method comprises the following steps: adding a metal chloride into a glutamic acid-halocarboxylic acid ionic liquid, reacting at 100 °C to 140 °C for 2 h to 6 h, adding a sodium alkali salt, and reacting at 70 °C to 110 °C to obtain the metal-organic framework porous polymer material; wherein the halocarboxylic acid is at least one of 3-chloropropionic acid, 4-(chloromethyl)benzoic acid, 3-bromopropionic acid or bromoacetic acid; and the metal chloride is zirconium chloride, iron chloride, zinc chloride or aluminum chloride. The metal-organic framework polymer material prepared by the specific method of the present invention has the advantages of high porosity, many active centers, large specific surface area, is convenient to separate and recover from the system, has good thermal stability, and the catalytic activity does not decrease significantly after being reused multiple times, and has broad application prospects in the field of synthesizing trimethylolethane.

Description

Technical Field

[0001] The present invention relates to the technical field of trimethylolethane preparation, and particularly relates to a metal-organic framework porous polymer material, a preparation method thereof, and an application thereof. Background Art

[0002] Trimethylolethane (TME) is an important chemical intermediate and fine chemical product. It can react with organic acids to form monoesters or polyesters. So far, trimethylolethane is mainly used in the synthesis of alkanoic resins, lubricants, plasticizers, coating agents, crosslinking agents, and phase change materials. Trimethylolethane is also widely used in the synthesis of thermal fibers and clothing, and has been extended to fields such as medical, health care, automotive, and military. In recent years, the demand has been increasing continuously.

[0003] Currently, trimethylolethane is mainly prepared by two-step reactions of formaldehyde and propionaldehyde through hydroxy condensation reaction and disproportionation reaction. The catalysts used for preparing trimethylolethane are mainly organic amine catalysts and inorganic base catalysts. Among them, organic amine catalysts have a high price and are not easy to be used in industrial-scale production applications; inorganic base catalysts are soluble in water and are not easy to be reused. In addition, since the preparation of trimethylolethane requires two different reactions, generally two different catalysts need to be added to improve the yield and purity of the product, which increases the production cost and prolongs the production cycle, restricting the large-scale production application of trimethylolethane. Therefore, developing a new catalyst with high catalytic activity, high selectivity, good stability, and capable of accelerating the production efficiency of trimethylolethane is of great significance for expanding the application scope of trimethylolethane. Summary of the Invention

[0004] Aiming at the problem that two different catalysts need to be added in the existing synthesis of trimethylolethane, resulting in low production efficiency and high production cost of trimethylolethane, the present invention provides a metal-organic framework porous polymer material.

[0005] And, a preparation method of a metal-organic framework porous polymer material.

[0006] And, an application of a metal-organic framework porous polymer material.

[0007] To achieve the above invention purpose, the embodiments of the present invention adopt the following technical solutions:

[0008] The present invention provides a preparation method of a metal-organic framework porous polymer material, including the following steps:

[0009] Step a, using glutamic acid and a halogenated carboxylic acid as raw materials, and reacting to obtain a glutamic acid-halogenated carboxylic acid ionic liquid;

[0010] Step b: Add metal chloride to the glutamic acid-halocarboxylic acid ionic liquid, heat up to 100°C - 140°C for reaction to obtain a reaction solution.

[0011] Step c: Add sodium base salt to the reaction solution, heat up to 70°C - 110°C for reaction, and separate to obtain the metal-organic framework porous polymer material.

[0012] Wherein, the halocarboxylic acid is at least one of 3-chloropropionic acid, 4-(chloromethyl)benzoic acid, 3-bromopropionic acid or bromoacetic acid; the metal chloride is zirconium chloride, iron chloride, zinc chloride or aluminum chloride.

[0013] Compared with the prior art, the preparation method of the metal-organic framework porous polymer material provided by the present invention uses the green and environmentally friendly glutamic acid-halocarboxylic acid ionic liquid as a raw material, conducts a polymerization reaction with a specific metal chloride to prepare a metal-organic framework polymer, and introduces alkaline ions into the metal-organic framework polymer through subsequent ion exchange, significantly improving the catalytic activity of the metal-organic framework polymer. Moreover, the metal-organic framework polymer material prepared by the specific method of the present invention has the advantages of high porosity, many active centers and large specific surface area, which is beneficial to achieving the purpose of one-pot synthesis of the target product, and is convenient for separation and recovery from the system, has good thermal stability, and the catalytic activity does not decrease significantly after repeated use for many times. It is a novel catalyst material with great application value and broad potential application fields.

[0014] Preferably, the halocarboxylic acid is 4-(chloromethyl)benzoic acid and the metal chloride is zirconium chloride.

[0015] The metal-organic framework polymer prepared from the preferred halocarboxylic acid and metal chloride has high catalytic activity for the synthesis reaction of trimethylolethane.

[0016] Preferably, step a is specifically: Dissolve glutamic acid and halocarboxylic acid in an organic solvent, heat up to 60°C - 100°C for reaction for 8h - 12h to obtain a glutamic acid-halocarboxylic acid ionic liquid.

[0017] Preferably, in step a, the organic solvent is at least one of anhydrous ethanol, propanol, n-butanol, chloroform or ether.

[0018] Preferably, in step a, the molar ratio of glutamic acid to halocarboxylic acid is 1:1 - 1:5.

[0019] Preferably, in step a, the volume-mass ratio of the organic solvent to glutamic acid is (7 - 15) mL:1 g.

[0020] The preferred organic solvent and the ratio of the organic solvent to the raw materials are beneficial to fully dissolve the raw materials, thus facilitating the subsequent reaction of glutamic acid and halocarboxylic acid to form an ionic liquid.

[0021] Preferably, in step b, the molar ratio of the metal chloride to glutamic acid is 1:1 to 1:5.

[0022] Preferably, in step b, the reaction time is 2 h to 6 h.

[0023] The preferred proportion of reaction raw materials and reaction time can promote the full progress of the reaction, help to disperse the crystal grains, improve the dispersibility of the prepared metal-organic framework polymer material, ensure the formation of a stable framework structure of the metal-organic framework material, and have a large specific surface area and high porosity, so that the prepared metal-organic framework polymer material has excellent catalytic activity.

[0024] Preferably, in step c, the sodium alkali salt is at least one of sodium methoxide, sodium carbonate or sodium silicate.

[0025] Preferably, in step c, the molar ratio of the sodium alkali salt to glutamic acid is 1:1 to 1:5.

[0026] Preferably, in step c, the reaction time is 2 h to 6 h.

[0027] The preferred sodium alkali salt, as well as the addition ratio and reaction time, are beneficial to the full ion exchange of chloride ions and alkaline ions in the metal-organic framework polymer material, and improve the catalytic activity of the metal-organic framework polymer material.

[0028] The present invention also provides a metal-organic framework porous polymer material prepared by the preparation method of the metal-organic framework porous polymer material described in any one of the above.

[0029] The metal-organic framework polymer material provided by the present invention uses Zr, Fe, Zn or Al as the active center and glutamic acid-halocarboxylic acid ionic liquid as the ligand, and has the advantages of high porosity, large specific surface area, many active sites, high thermal stability, etc. At the same time, it also has the advantages of easy recovery and multiple reuse, and the preparation method is simple, the raw materials are easy to obtain, green and environmentally friendly, suitable for industrial production applications, and is a catalyst material with high application value.

[0030] The present invention also provides the application of the above metal-organic framework porous polymer material as a catalyst for preparing trimethylolethane.

[0031] Exemplarily, the addition amount of the metal-organic framework porous polymer material as a catalyst is 18% to 22% of the propionaldehyde patent.

[0032] In the prior art, the catalysts for the preparation of trimethylolethane generally have the disadvantages of high cost and inability to be recycled. Moreover, the current process for synthesizing trimethylolethane involves two different organic reactions, and it is difficult for a single catalyst to achieve high selectivity and high activity catalysis. The metal-organic framework porous polymer material provided by the present invention can catalyze different types of organic reactions, realizing the purpose of green synthesis of trimethylolethane by a one-pot method for tandem reactions. Moreover, it has high catalytic activity and selectivity, is easy to separate from the reaction system, has good stability, can be reused, and has broad application prospects in the field of synthesizing trimethylolethane. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is the thermogravimetric analysis diagram of the metal-organic framework porous polymer material prepared in Example 1 of the present invention;

[0034] Figure 2 It is the N 2 adsorption and desorption curve of the metal-organic framework porous polymer material prepared in Example 1 of the present invention;

[0035] Figure 3 It is the pore size distribution curve of the metal-organic framework porous polymer material prepared in Example 1 of the present invention;

[0036] Figure 4 It is the catalytic performance diagram of the metal-organic framework porous polymer material prepared by the present invention for recycling. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0038] To better illustrate the present invention, further examples are given below through embodiments.

[0039] Example 1

[0040] A preparation method of a metal-organic framework porous polymer material:

[0041] Step 1: Weigh 4.41 g of glutamic acid and 5.12 g of 4-(chloromethyl)benzoic acid, dissolve them in 50 mL of absolute ethanol, heat up to 60 °C and react for 10 h to obtain an ionic liquid;

[0042] Step 2: Add 3.35 g of zirconium chloride to the above ionic liquid, mix evenly, heat up to 120 °C and react for 4 h to obtain a reaction solution;

[0043] Step 3: Add 1.62 g of sodium methoxide to the reaction solution, heat up to 80 °C and react for 6 h, filter and dry to obtain a metal-organic framework porous polymer material.

[0044] The thermogravimetric analysis diagram of the metal-organic framework porous polymer material prepared in this example is as follows Figure 1 shown. It can be seen from the figure that even when the catalyst is heated to 288 °C, the weight loss rate is only 10%, and when the temperature reaches 566 °C, the weight loss rate is only 40%. Therefore, it is proved that the catalyst has good thermal stability and is suitable for the preparation of trimethylolethane.

[0045] Using N 2 adsorption-desorption experiments to characterize the specific surface area and pore size distribution of the metal-organic framework porous polymer material prepared in this example. Among them, the N 2 adsorption equilibrium isotherm of the metal-organic framework porous polymer material is as follows Figure 2 shown, and the pore size distribution diagram is as follows Figure 3 shown (calculated using the Barrett-Joyner-Hallender (BJH) desorption model). It can be seen from the figure that the adsorption-desorption of the metal-organic framework porous polymer material shows a typical type IV hysteresis loop. The specific surface area, pore volume and pore size are shown in Table 1. The pore size of the metal-organic framework porous polymer material prepared in this example is mainly concentrated around 3 nm, belonging to mesoporous materials.

[0046] Table 1 Specific surface area, pore volume and pore size of metal-organic framework porous polymer materials

[0047] <![CDATA[Specific surface area (m 2 ·g -1 )]]> <![CDATA[Pore volume (cm 3 ·g -1 )]]> Pore size nm 68.602 0.134 3.169

[0048] Example 2

[0049] A preparation method of a metal-organic framework porous polymer material:

[0050] Step 1: Weigh 4.41 g of glutamic acid and 1.85 g of 4-(chloromethyl)benzoic acid, dissolve them in 35 mL of absolute ethanol, and raise the temperature to 80 °C for reaction for 12 h to obtain an ionic liquid;

[0051] Step 2: Add 6.7 g of zirconium chloride to the above ionic liquid, mix evenly, and raise the temperature to 100 °C for reaction for 6 h to obtain a reaction solution;

[0052] Step 3: Add 0.63 g of sodium methoxide to the reaction solution, raise the temperature to 70 °C for reaction for 6 h, filter, and dry to obtain a metal-organic framework porous polymer material.

[0053] Example 3

[0054] A preparation method of a metal-organic framework porous polymer material:

[0055] Step 1: Weigh 4.41 g of glutamic acid and 1.05 g of 4-(chloromethyl)benzoic acid, dissolve them in 65 mL of absolute ethanol, heat up to 100 °C and react for 8 h to obtain an ionic liquid;

[0056] Step 2: Add 1.45 g of zirconium chloride to the above ionic liquid, mix evenly, heat up to 140 °C and react for 2 h to obtain a reaction solution;

[0057] Step 3: Add 0.35 g of sodium methoxide to the reaction solution, heat up to 100 °C and react for 2 h, filter and dry to obtain a metal-organic framework porous polymer material.

[0058] Example 4

[0059] A preparation method of a metal-organic framework porous polymer material:

[0060] Step 1: Weigh 4.41 g of glutamic acid and 4.59 g of 3-bromopropionic acid, dissolve them in 50 mL of absolute ethanol, heat up to 60 °C and react for 10 h to obtain an ionic liquid;

[0061] Step 2: Add 2.35 g of ferric chloride to the above ionic liquid, mix evenly, heat up to 120 °C and react for 4 h to obtain a reaction solution;

[0062] Step 3: Add 1.62 g of sodium methoxide to the reaction solution, heat up to 80 °C and react for 6 h, filter and dry to obtain a metal-organic framework porous polymer material.

[0063] Example 5

[0064] A preparation method of a metal-organic framework porous polymer material:

[0065] Step 1: Weigh 4.41 g of glutamic acid and 3.23 g of 3-chloropropionic acid, dissolve them in 50 mL of absolute ethanol, heat up to 60 °C and react for 10 h to obtain an ionic liquid;

[0066] Step 2: Add 2 g of zinc chloride to the above ionic liquid, mix evenly, heat up to 120 °C and react for 4 h to obtain a reaction solution;

[0067] Step 3: Add 3.18 g of sodium carbonate to the reaction solution, heat up to 80 °C and react for 6 h, filter and dry to obtain a metal-organic framework porous polymer material.

[0068] Example 6

[0069] A preparation method of a metal-organic framework porous polymer material:

[0070] Step 1: Weigh 4.41 g of glutamic acid and 2.84 g of chloroacetic acid, dissolve them in 50 mL of absolute ethanol, heat up to 60 °C and react for 10 h to obtain an ionic liquid;

[0071] Step 2: Add 1.92 g of aluminum chloride to the above ionic liquid, mix evenly, heat up to 120 °C and react for 4 h to obtain a reaction solution;

[0072] Step 3: Add 3.66 g of sodium silicate to the reaction solution, heat up to 80 °C and react for 6 h, filter and dry to obtain a metal-organic framework porous polymer material.

[0073] Comparative Example 1

[0074] This comparative example provides a preparation method of a metal-organic framework porous polymer material. The specific steps are exactly the same as those in Example 1, except that 4-(chloromethyl)benzoic acid is replaced with an equimolar amount of dichloroacetic acid. The specific steps are as follows:

[0075] Step 1: Weigh 4.41 g of glutamic acid and 3.87 g of dichloroacetic acid, dissolve them in 50 mL of absolute ethanol, heat up to 60 °C and react for 10 h to obtain an ionic liquid;

[0076] Step 2: Add 3.35 g of zirconium chloride to the above ionic liquid, mix evenly, heat up to 120 °C and react for 4 h to obtain a reaction solution;

[0077] Step 3: Add 1.62 g of sodium methoxide to the reaction solution, heat up to 80 °C and react for 6 h, filter and dry to obtain a metal-organic framework porous polymer material.

[0078] Application Example

[0079] Apply the metal-organic framework porous polymer materials prepared in Examples 1-6 and Comparative Example 1 as catalysts for the preparation of trimethylolethane. The specific steps for the preparation of trimethylolethane are as follows:

[0080] Add 24.3 g of formaldehyde solution (mass concentration 37%) and 4.86 g of the metal-organic framework porous polymer material to a three-necked flask, heat up to 30 °C, keep the temperature and dropwise add 4.86 g of propionaldehyde, react for 2 h, then heat up to 65 °C and continue to react for 2.5 h to obtain trihydroxyethane.

[0081] The catalytic performance results of each example and comparative example are shown in Table 2. The conversion rate and selectivity are calculated by gas chromatography using the internal standard method. The calculation formulas are as follows:

[0082] Conversion rate = (m 丙醛总量 - m 未反应丙醛 ) / m 丙醛总量 × 100%

[0083] Selectivity = (m 三羟甲基乙烷 / M 三羟甲基乙烷 ) / [(m 丙醛总量 - m 未反应丙醛 ) / M 丙醛× 100%

[0084] Table 2 Catalysis Results

[0085] Conversion rate (%) Selectivity (%) Example 1 98.34 86.90 Example 2 96.89 85.43 Example 3 95.03 83.92 Example 4 78.74 64.32 Example 5 75.43 67.29 Example 6 70.61 65.66 Comparative Example 1 65.83 52.67

[0086] Comparative Example 2

[0087] This comparative example provides a method for preparing trimethylolethane, and the specific steps are as follows:

[0088] Add 15.6 g of distilled water and 14.6 g of triethylamine compound into a flat-bottom flask, and dropwise add 12 g of acetic acid. The dropping time is controlled for 30 min. After dropping, continue stirring for 1 h. Then add 24.3 g of formaldehyde solution (mass concentration 37%) into the above flat-bottom flask. Dropwise add propionaldehyde at 30°C, react for 2 h, and then raise the temperature to 65°C and react for 2.5 h to obtain trimethylolethane.

[0089] The conversion rate of preparing trihydroxyethane in this comparative example is 63.44%, and the selectivity is 50.61%.

[0090] Reusability

[0091] In order to demonstrate the recycling performance of the metal-organic framework porous polymer material prepared in the examples of the present invention, the following reuse test is carried out, and the specific experimental steps are as follows:

[0092] Filter the reaction solution after the application example test, wash it twice with ethanol and distilled water in sequence, and then dry it at 100°C for 12 h to obtain the regenerated metal-organic framework porous polymer material.

[0093] Carry out the preparation test of trimethylolethane on the regenerated metal-organic framework porous polymer material according to the steps in the application example part. The results are as Figure 4 shown.

[0094] In this test, the metal-organic framework porous polymer material prepared in Example 1 is used. The number of cycles refers to the number of times the metal-organic framework porous polymer material is washed and regenerated.

[0095] As can be seen from the figure, after 5 cycles of the metal-organic framework porous polymer material prepared in Example 1, it still has high catalytic performance. After 5 cycles, the selectivity can still reach 98%, and the conversion rate can still reach 86%, showing good reusability.

[0096] In summary, the metal-organic framework porous polymer material prepared in the examples of the present invention has excellent catalytic performance and recycling performance, can achieve efficient catalysis of the trimethylolethane synthesis reaction, is easy to separate and recover from the system, can be recycled, and has broad application prospects in the field of synthesizing trimethylolethane.

[0097] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, or improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A preparation method of a metal-organic framework porous polymer material, characterized in that, it comprises the following steps: Step a, using glutamic acid and a halogenated carboxylic acid as raw materials, reacting to obtain a glutamic acid-halogenated carboxylic acid ionic liquid; Step b, adding a metal chloride to the glutamic acid-halogenated carboxylic acid ionic liquid, heating to 100 °C to 140 °C for reaction to obtain a reaction solution; Step c, adding a sodium alkali salt to the reaction solution, heating to 70 °C to 110 °C for reaction, and separating to obtain the metal-organic framework porous polymer material; wherein, the halogenated carboxylic acid is at least one of 3-chloropropionic acid, 4-(chloromethyl)benzoic acid, 3-bromopropionic acid or bromoacetic acid; the metal chloride is zirconium chloride, iron chloride, zinc chloride or aluminum chloride.

2. The preparation method of the metal-organic framework porous polymer material according to claim 1, characterized in that, the halogenated carboxylic acid is 4-(chloromethyl)benzoic acid, and the metal chloride is zirconium chloride.

3. The preparation method of the metal-organic framework porous polymer material according to claim 1 or 2, characterized in that, Step a is specifically: dissolving glutamic acid and a halogenated carboxylic acid in an organic solvent, heating to 60 °C to 100 °C for reaction for 8 h to 12 h to obtain a glutamic acid-halogenated carboxylic acid ionic liquid.

4. The preparation method of the metal-organic framework porous polymer material according to claim 3, characterized in that, in Step a, the organic solvent is at least one of absolute ethanol, propanol, n-butanol, chloroform or ether.

5. The preparation method of the metal-organic framework porous polymer material according to claim 3, characterized in that, in Step a, the molar ratio of glutamic acid to the halogenated carboxylic acid is 1:1 to 1:5; and / or in Step a, the volume-mass ratio of the organic solvent to glutamic acid is (7 - 15) mL:1 g.

6. The preparation method of the metal-organic framework porous polymer material according to claim 1, characterized in that, in Step b, the molar ratio of the metal chloride to glutamic acid is 1:1 to 1:5; and / or in Step b, the reaction time is 2 h to 6 h.

7. The preparation method of the metal-organic framework porous polymer material according to claim 1, characterized in that, in Step c, the sodium alkali salt is at least one of sodium methoxide, sodium carbonate or sodium silicate.

8. The preparation method of the metal-organic framework porous polymer material according to claim 1 or 7, characterized in that, in Step c, the molar ratio of the sodium alkali salt to glutamic acid is 1:1 to 1:5; and / or in Step c, the reaction time is 2 h to 6 h.

9. A metal-organic framework porous polymer material, characterized in that, it is prepared by the preparation method of the metal-organic framework porous polymer material according to any one of claims 1 - 8.

10. Application of the metal-organic framework porous polymer material according to claim 9 as a catalyst for preparing trimethylolethane.

Images