Catalytic oxidation method of cyclododecatriene

Abstract

The present invention relates to a cyclododecatriene catalytic oxidation method, which comprises that cyclododecatriene, an oxidizing agent, an optional solvent and a catalyst are contacted to carry out an oxidation reaction, and the catalyst is a graphene-loaded polyacid catalyst. The graphene-loaded polyacid catalyst is used for catalytic oxidation of cyclododecatriene, so that the raw material conversion rate and the selectivity of the target product dodecanedioic acid can be effectively improved.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a catalytic oxidation method of cyclododecatriene. BACKGROUND

[0002] With the rapid development of science and technology, the epoxidation technology of macrocyclic olefins is constantly progressing and increasingly attracting attention. Among them, cyclododecatriene is one of the main macrocyclic polyenes produced in the process of petroleum chemical production, is an important organic chemical raw material, and has a wide application prospect. Its complete oxidation can obtain diacid product, which has high industrial value, for example, can be used to prepare lubricants, plasticizers, etc. However, the completeness of the catalytic oxidation reaction of cyclododecatriene as a raw material in the prior art is insufficient, resulting in low selectivity of diacid product. SUMMARY

[0003] The purpose of the present disclosure is to provide a catalytic oxidation method of cyclododecatriene to improve the selectivity of diacid product.

[0004] In order to achieve the above-mentioned purpose, the present disclosure provides a catalytic oxidation method of cyclododecatriene, which comprises: contacting cyclododecatriene, an oxidizing agent, a solvent and a catalyst to perform an oxidation reaction, wherein the catalyst is a graphene supported polyacid catalyst.

[0005] Optionally, the preparation step of the catalyst comprises:

[0006] mixing graphene and polyacid to obtain a mixture;

[0007] adding water to the mixture, then placing it in a sealed reactor for treatment, and drying the obtained product to obtain a graphene supported polyacid catalyst.

[0008] Optionally, the graphene is prepared by a supercritical carbon dioxide exfoliation method; and / or,

[0009] The D50 particle size of the graphene is 0.5-5 pm, the flake size is 1-10000 nm, the number of layers is 10 layers or less, and the specific surface area is 100-800 m 2 / g.

[0010] Optionally, the polyacid is at least one selected from phosphotungstic heteropoly acid, phosphomolybdic heteropoly acid, silicotungstic heteropoly acid, silicomolybdic heteropoly acid, phosphotungsten vanadium heteropoly acid and phosphomolybdenum vanadium heteropoly acid.

[0011] Optionally, the weight ratio of the graphene to the polyacid is 1:(0.1-1).

[0012] Optionally, the mixing conditions include: temperature 10-60℃, time 1-12h; and / or,

[0013] The conditions of the treatment include: temperature of 100-200℃, time of 2-24h.

[0014] Optionally, the weight ratio of the cyclododecatriene, the oxidizing agent, the solvent and the catalyst is 1:(5-20):(2-50):(0.1-5).

[0015] Optionally, the oxidizing agent is one or more selected from hydrogen peroxide, tert-butyl hydroperoxide, phenethyl hydroperoxide, cumyl hydroperoxide, cyclohexyl hydroperoxide, peroxyacetic acid and peroxypropionic acid.

[0016] Optionally, the solvent is one or more selected from methanol, ethanol, n-propanol, isopropanol, tert-butyl alcohol, isobutyl alcohol, acetone, butanone and acetonitrile.

[0017] Optionally, the conditions of the oxidation reaction include: temperature of 30-120℃, time of 1-12h.

[0018] By the above technical solution, the graphene-supported polyacid catalyst is used for catalytic oxidation of cyclododecatriene, which can effectively improve the raw material conversion rate and the selectivity of the target product dodecanedioic acid.

[0019] Other features and advantages of the present disclosure will be described in detail in the following specific embodiments section. DETAILED DESCRIPTION

[0020] The specific embodiments of the present disclosure are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure, and are not used to limit the present disclosure.

[0021] In a first aspect of the present disclosure, a cyclododecatriene catalytic oxidation method is provided, which comprises: contacting cyclododecatriene, an oxidizing agent, a solvent and a catalyst to perform an oxidation reaction, wherein the catalyst is a graphene-supported polyacid catalyst.

[0022] The present disclosure uses a graphene-supported polyacid catalyst to perform catalytic oxidation of cyclododecatriene (chemical formula: C 12 H 18 , CAS number: 16988-38-6), which exhibits good catalytic activity and complete catalytic performance for cyclic macromolecules, and can effectively improve the raw material conversion rate and the selectivity of the target product dodecanedioic acid.

[0023] In a specific embodiment, the graphene-supported polyacid catalyst contains 10-50wt% of polyacid, preferably 15-35wt% of polyacid, based on the total weight of the graphene-supported polyacid catalyst.

[0024] In one specific embodiment, the method provided by the present disclosure comprises the following steps S1-S3:

[0025] S1, mixing graphene with a polyacid to obtain a mixture;

[0026] S2, adding water to the mixture, then placing it in a closed reactor for treatment, and drying the obtained product to obtain a graphene-supported polyacid catalyst;

[0027] S3, contacting cyclododecatriene, an oxidizing agent, and optionally a solvent with the graphene-supported polyacid catalyst for oxidation reaction.

[0028] In step S1, the graphene can be in the form of powder. In one specific embodiment, the D50 particle size of the graphene can be 0.5-5 μm, preferably 1-2.5 μm; the flake size can be 1-10000 nm, preferably 10-5000 nm; the number of layers can be 10 or less, preferably 8 or less; and the specific surface area can be 100-800 m 2 / g, preferably 150-600 m 2 / g.

[0029] In one preferred embodiment, the graphene is prepared by a supercritical carbon dioxide exfoliation method. The graphene powder prepared by the supercritical carbon dioxide exfoliation method has a more uniform particle size distribution and fewer layers, which is beneficial to further improve the catalytic activity of the catalyst. Specifically, the preparation steps of the graphene can comprise: adding graphite into a reaction kettle, sealing the reaction kettle, introducing a gaseous intercalation medium (i.e. carbon dioxide) into the reaction kettle, and controlling the pressure in the reaction kettle at 1-200 atm by adjusting the gas inlet amount of the gaseous intercalation medium. Under this pressure and stirring condition, the temperature of the system is raised to 25-500°C for 0.1-24 h of molecular intercalation reaction. After the reaction is completed, the pressure in the reaction kettle is rapidly reduced to half or less of the pressure in the reaction kettle within 0.1 s, and then the gas is released to normal pressure. The buffer tank is opened to obtain graphene.

[0030] The polyacid is a nanoscale metal-oxygen cluster compound formed by high oxidation state of a pre-transition metal ion (such as V, Mo, W, etc.) and oxygen, which has excellent redox performance. Specifically, the polyacid can be a heteropoly acid and / or a homopoly acid.

[0031] In one specific embodiment, the polyacid can be selected from phosphotungstic heteropoly acid (H3PW 12 O 40 ·xH2O), phosphomolybdic heteropoly acid (H3PMo 12 O 40 ·xH2O), silicotungstic heteropoly acid (H4SiW 12O 40 at least one of silicomolybdovanadophosphoric acid (H4[PMo 12 O 40 at least one of silicomolybdovanadophosphoric acid (H4[PMo 11 VO 40 ] x H2O) and phosphomolybdovanadophosphoric acid (H4[PMo 11 VO 40 ] x H2O) and phosphomolybdovanadophosphoric acid (H4[PMo 12 O 40 at least one of silicomolybdovanadophosphoric acid (H4[PMo 12 O 40 at least one of silicomolybdovanadophosphoric acid (H4[PMo

[0032] The ratio of the graphene to the polyacid can be adjusted within a certain range. In one specific embodiment, the weight ratio of the graphene to the polyacid can be 1 : (0.1-1), preferably 1 : (0.2-0.5). The conditions for mixing the graphene and the polyacid can include a temperature of 10-60°C, preferably 25-45°C, and a time of 1-12 h, preferably 2-8 h.

[0033] In step S2, the amount of water can be adjusted within a certain range. In one specific embodiment, the amount of water is such that the system is saturated (i.e., saturated steam) at the treatment temperature, and specifically, the weight ratio of the mixture to water can be 1 : (0.1-10), preferably 1 : (0.2-5).

[0034] The conditions for the treatment can include a temperature of 100-200°C, preferably 120-180°C, autogenous pressure, and a time of 2-24 h, preferably 6-12 h. The conditions for drying can be conventional conditions in the art.

[0035] In step S3, the weight ratio of the cyclododecatriene, the oxidant, the solvent, and the catalyst can be 1 : (5-20) : (2-50) : (0.1-5), preferably 1 : (8-15) : (5-25) : (0.2-2).

[0036] The oxidizing agent can be one or more selected from the group consisting of hydrogen peroxide, t-butyl hydroperoxide, phenethyl hydroperoxide, cumyl hydroperoxide, cyclohexyl hydroperoxide, peroxyacetic acid, and peroxypropionic acid, and is preferably hydrogen peroxide. The oxidizing agent can be in the form of an aqueous solution, and the concentration thereof can be, for example, 10 to 40% by weight. The solvent can be water and / or a common organic solvent, and can be one or more selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, t-butyl alcohol, isobutyl alcohol, acetone, butanone, and acetonitrile.

[0037] The conditions of the oxidation reaction can include a temperature of 30 to 120°C, preferably 40 to 90°C, and a time of 1 to 12 h, preferably 2 to 6 h.

[0038] The method of the present disclosure can effectively improve the conversion rate of the raw material and the selectivity of the target product dodecanedioic acid (chemical formula: C 12 H 22 O4, CAS No. 693-23-2). Specifically, the conversion rate of the raw material can reach more than 20%, and the selectivity of dodecanedioic acid can reach more than 70%.

[0039] The present disclosure will be further described below by way of examples, but the present disclosure is not limited in any way by the examples.

[0040] Example 1

[0041] (1) Graphene was prepared by a supercritical carbon dioxide exfoliation method. Specifically, 1 g of graphite was added to a reaction kettle, gaseous intercalation medium (carbon dioxide) was introduced into the reaction kettle, and the pressure in the reaction kettle was controlled at 1 atm by adjusting the amount of gaseous intercalation medium introduced. Under the conditions of this pressure and a stirring speed of 200 rpm, the temperature of the system was raised to 200°C to perform a molecular intercalation reaction. After 0.5 h of reaction, the pressure in the reaction kettle was rapidly reduced to half or less of the pressure in the reaction kettle within 0.1 s, and then the gas was released to normal pressure. The buffer tank was opened, and 0.9 g of graphene powder was obtained. The D50 particle size of the graphene powder was 1.8 μm, the flake size was 870 to 1880 nm, the number of layers was 3 to 8, and the specific surface area was 221 m 2 / g.

[0042] (2) The above graphene was mixed with phosphotungstic heteropoly acid (H3PW 12 O 40• 5H2O) were mixed in a weight ratio of 1 :0.34 and stirred at 40°C for 2 h to obtain a mixture; the mixture was sealed in a closed reactor after introducing an appropriate amount of water that can form saturated steam (weight ratio of mixture to water was 1 :1) and treated at 150°C under autogenous pressure for 12 h. The reaction product was dried to obtain a graphene-supported phosphotungstic heteropoly acid catalyst, which contained 24.6 wt% phosphotungstic heteropoly acid based on the weight of the dry base.

[0043] (3) Under nitrogen protection, cyclododecatriene, 30 wt% hydrogen peroxide, methanol, and the above catalyst were added to a 250 mL Parr reactor in a weight ratio of 1 :9:20:1, respectively, and stirred at 60°C under autogenous pressure for 6 h after sealing. After the reaction was completed, the reaction product was distilled under reduced pressure, and the product was collected. The composition of the product after the reaction was analyzed by distillation, crystallization, and weighing, and the cyclododecatriene conversion rate and dodecanedioic acid selectivity were calculated according to the following formula. The results are shown in Table 1.

[0044] Cyclododecatriene conversion rate = (weight of cyclododecatriene input - weight of cyclododecatriene remaining after reaction) / weight of cyclododecatriene input x 100%

[0045] Dodecanedioic acid selectivity = (weight of dodecanedioic acid in product / total weight of product) x 100%

[0046] Example 2

[0047] The catalyst was prepared according to the method of Example 1, except that in step (2), graphene and silicotungstic heteropoly acid (H4SiMo 12 O 40 • 5H2O) were mixed in a weight ratio of 1 :0.34 and stirred at 40°C for 2 h to obtain a mixture; the mixture was sealed in a closed reactor after introducing an appropriate amount of water that can form saturated steam (weight ratio of mixture to water was 1 :1) and treated at 150°C under autogenous pressure for 12 h. The reaction product was dried to obtain a graphene-supported phosphotungstic heteropoly acid catalyst, which contained 24.6 wt% phosphotungstic heteropoly acid based on the weight of the dry base.

[0048] Example 3

[0049] The catalyst was prepared according to the method of Example 1, except that the graphene powder prepared in step (1) had a D50 particle size of 0.5 μm, a sheet diameter of 560–2900 nm, 3–6 layers, and a specific surface area of ​​310 m². 2 / g. A graphene-supported phosphotungstic heteropolyacid catalyst was prepared using this graphene, with a phosphotungstic heteropolyacid content of 24.6% by weight on a dry basis. The catalytic oxidation of cyclododecanetriene was carried out using this catalyst, and the conversion rate of cyclododecanetriene and the selectivity of the target product dodecanoic acid were calculated. The results are shown in Table 1.

[0050] Example 4

[0051] The catalyst was prepared using the method of Example 1, the only difference being that the graphene powder prepared in step (1) had a D50 particle size of 5 μm, a sheet diameter of 2500–7000 nm, 6–10 layers, and a specific surface area of ​​115 m². 2 / g. A graphene-supported phosphotungstic heteropolyacid catalyst was prepared using this graphene, with a phosphotungstic heteropolyacid content of 24.6% by weight on a dry basis. The catalytic oxidation of cyclododecanetriene was carried out using this catalyst, and the conversion rate of cyclododecanetriene and the selectivity of the target product dodecanoic acid were calculated. The results are shown in Table 1.

[0052] Example 5

[0053] The catalyst was prepared according to the method in Example 1, except that the graphene powder used in this example (purchased from Changzhou Sixth Element Materials Technology Co., Ltd., trade number SE1233, prepared by redox method) had a D50 particle size of 2.6 μm, a sheet diameter of 2100–4300 nm, 2–6 layers, and a specific surface area of ​​242 m². 2 / g. A graphene-supported phosphotungstic heteropolyacid catalyst was prepared using this graphene, with a phosphotungstic heteropolyacid content of 24.6% by weight on a dry basis. The catalytic oxidation of cyclododecanetriene was carried out using this catalyst, and the conversion rate of cyclododecanetriene and the selectivity of the target product dodecanoic acid were calculated. The results are shown in Table 1.

[0054] Example 6

[0055] The catalytic oxidation of cyclododecanetriene was carried out according to the method of Example 1, except that in step (2), the weight ratio of graphene to phosphotungstic heteropolyacid was 1:0.15, and the phosphotungstic heteropolyacid content of the graphene-supported catalyst was 12.7% by weight (on a dry basis). The catalytic oxidation reaction of cyclododecanetriene was carried out using this catalyst, and the conversion rate of cyclododecanetriene and the selectivity of the target product dodecanoic acid were calculated. The results are shown in Table 1.

[0056] Example 7

[0057] The catalytic oxidation of cyclododecatriene was carried out according to the method of Example 1, the only difference being that in step (2), the weight ratio of graphene to phosphotungstic heteropoly acid was 1:1, and a graphene-supported phosphotungstic heteropoly acid catalyst was prepared, the phosphotungstic heteropoly acid content of which was 48.5% by weight (based on the dry weight). The catalytic oxidation reaction of cyclododecatriene was carried out using the catalyst, and the cyclododecatriene conversion rate and the dodecanedioic acid selectivity of the target product were calculated, and the results are shown in Table 1.

[0058] Example 8

[0059] The catalytic oxidation of cyclododecatriene was carried out according to the method of Example 1, the only difference being that in step (3), the weight ratio of cyclododecatriene, 30% by weight of hydrogen peroxide, methanol and catalyst was 1:20:50:5. The cyclododecatriene conversion rate and the dodecanedioic acid selectivity of the target product were calculated, and the results are shown in Table 1.

[0060] Comparative Example 1

[0061] The catalytic oxidation of cyclododecatriene was carried out according to the method of Example 1, the only difference being that in this comparative example, graphene in Example 1 was used as a catalyst for the catalytic oxidation of cyclododecatriene, and the cyclododecatriene conversion rate and the dodecanedioic acid selectivity of the target product were calculated, and the results are shown in Table 1.

[0062] Comparative Example 2

[0063] The catalytic oxidation of cyclododecatriene was carried out according to the method of Example 1, the only difference being that in this comparative example, phosphotungstic heteropoly acid (H3PW 12 O 40 ·5H2O) in Example 1 was used as a catalyst for the catalytic oxidation of cyclododecatriene, and the cyclododecatriene conversion rate and the dodecanedioic acid selectivity of the target product were calculated, and the results are shown in Table 1.

[0064] Table 1

[0065]

[0066]

[0067] As can be seen from Table 1, the use of the catalyst provided by the present disclosure in the oxidation reaction of cyclododecatriene has a high raw material conversion rate and dodecanedioic acid selectivity.

[0068] The above describes the preferred embodiments of the present disclosure, but the present disclosure is not limited to the specific details in the above embodiments, and various simple modifications can be made to the technical solutions of the present disclosure within the technical concept of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

[0069] It should be further noted that various specific technical features described in the above specific embodiments can be combined in any suitable manner, and the disclosure will not be repeated here for various possible combinations.

[0070] In addition, various different embodiments of the disclosure can also be combined with each other as long as they do not contradict the idea of the disclosure, and they should also be considered as disclosed by the disclosure.

Claims

1. A method for the catalytic oxidation of cyclododecanetriene, characterized in that, The method includes: An oxidation reaction is carried out by contacting a cyclododecanetriene, an oxidant, a solvent, and a catalyst, wherein the catalyst is a graphene-supported polyacid catalyst.

2. The method according to claim 1, wherein, The catalyst preparation steps include: Graphene is mixed with polyacids to obtain a mixture. Water is added to the mixture, which is then placed in a closed reactor for processing. The resulting product is dried to obtain a graphene-supported polyacid catalyst.

3. The method according to claim 2, wherein, The graphene was prepared by supercritical carbon dioxide exfoliation; and / or, The graphene has a D50 particle size of 0.5–5 μm, a sheet diameter of 1–10000 nm, fewer than 10 layers, and a specific surface area of ​​100–800 m². 2 / g.

4. The method according to claim 2, wherein, The polyacid is selected from at least one of phosphotungstic heteropolyacid, phosphotimolecular heteropolyacid, silicotungstic heteropolyacid, silicomolecular heteropolyacid, phosphotungstic vanadium heteropolyacid, and phosphotimolecular vanadium heteropolyacid.

5. The method according to claim 2, wherein, The weight ratio of graphene to polyacid is 1:(0.1~1).

6. The method according to claim 2, wherein, The mixing conditions include: a temperature of 10–60°C and a time of 1–12 hours; and / or, The processing conditions include: a temperature of 100–200°C and a time of 2–24 hours.

7. The method according to claim 1, wherein, The weight ratio of the cyclododecanetriene, the oxidant, the solvent, and the catalyst is 1:(5-20):(2-50):(0.1-5).

8. The method according to claim 1, wherein, The oxidant is selected from one or more of hydrogen peroxide, tert-butyl hydrogen peroxide, phenethyl hydrogen peroxide, isopropylphenyl hydrogen peroxide, cyclohexyl hydrogen peroxide, peracetic acid, and peroxypropionic acid.

9. The method according to claim 1, wherein, The solvent is selected from one or more of methanol, ethanol, n-propanol, isopropanol, tert-butanol, isobutanol, acetone, butanone, and acetonitrile.

10. The method according to claim 1, wherein, The conditions for the oxidation reaction include: a temperature of 30–120°C and a time of 1–12 h.

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