Preparation method of a catalyst for synthesizing o-chlorocyclohexanone and application thereof

Abstract

The application provides a preparation method and application of a catalyst for synthesizing o-chlorocyclohexanone, wherein a catalyst carrier is treated in an acid solution, a first active component with a mass fraction is added, ultrasonic dispersion treatment is carried out under water bath condition, heat preservation and aging are carried out, water washing is carried out until neutral, and low-temperature drying is carried out, so as to obtain a catalyst precursor; the second active component is dissolved in an ethanol solution, and then added into the catalyst precursor, stirred, and then placed, treated in nitrogen, and calcined to obtain the catalyst. The catalyst can effectively catalyze one-step synthesis of o-chlorocyclohexanone from cyclohexene oxide, and the product yield is greater than 92%.

Description

Technical Field

[0001] This invention belongs to the field of catalyst preparation technology, specifically relating to a method for preparing a catalyst for synthesizing o-chlorocyclohexanone, and a method for synthesizing o-chlorocyclohexanone. Background Technology

[0002] o-Chlorocyclohexanone is used as an intermediate in organic synthesis. This product is mainly used in organic synthesis, such as the synthesis of o-hydroxycyclohexanone, catechol, o-chlorocyclohexanone oxime, furanocoumarins, etc. It can be used to produce rubber adhesives and accelerators, and also has significant applications in agriculture and medicine. Most synthetic methods are acid-catalyzed, with some base-catalyzed methods. However, the use of supported catalysts is relatively uncommon. Supported catalysts are solid, easily separated and recovered, and can be reused multiple times.

[0003] Early methods used chlorine gas as a chlorinating agent, but due to its high toxicity, later studies on o-chlorocyclohexanone explored using chlorine-containing products as chlorine sources, such as thioyl chloride, trichloroisocyanuric acid, p-benzenesulfonyl chloride, acetyl chloride, and hydrochloric acid. However, using thioyl chloride resulted in the difficult-to-dissolve byproduct dichlorocyclohexanone, leading to low yields; using trichloroisocyanuric acid generally yielded only 75%, and subsequent processing was complex; using p-benzenesulfonyl chloride required cooling the solution to -78°C, a complicated process; and using acetyl chloride resulted in cumbersome purification, making it unsuitable for industrial production.

[0004] Patent CN 107540531 describes a ring-opening reaction between light oil and hydrogen chloride solution in the presence of an additive to generate 2-chlorocyclohexanol. After settling and separation, an oil phase is obtained. This oil phase is then subjected to atmospheric or vacuum distillation to remove relatively low-boiling components, yielding high-purity 2-chlorocyclohexanol. This high-purity 2-chlorocyclohexanol is then reacted with an oxidant. After the reaction, the oil phase is washed with a washing solution, and the resulting oil phase is then subjected to atmospheric distillation. The fraction collected yields o-chlorocyclohexanone. This method offers high yield and a mild reaction, but it is a two-step process with a relatively long processing time.

[0005] Patent CN 113398978 discloses a method for preparing o-chlorocyclohexanone and its catalyst, which uses a supported cerium catalyst to effectively catalyze the one-step synthesis of o-chlorocyclohexanone from cyclohexane oxide. The process is simple and involves one-step synthesis of o-chlorocyclohexanone, but the selectivity is poor and the yield of o-chlorocyclohexanone is low. Summary of the Invention

[0006] This invention provides a method for preparing a catalyst for the synthesis of o-chlorocyclohexanone. A supported cerium catalyst is synthesized, and the preparation process is simple, environmentally friendly, and yields high selectivity and high yield of o-chlorocyclohexanone. The catalyst support is treated in an acid solution, a first active component is added, and the mixture is ultrasonically dispersed under water bath conditions, aged at a constant temperature, washed with water until neutral, and dried at low temperature to obtain the catalyst precursor. A second active component is dissolved in an ethanol solution and added to the catalyst precursor. After stirring and standing, the mixture is treated under nitrogen and calcined to obtain the catalyst. This catalyst can effectively catalyze the one-step synthesis of o-chlorocyclohexanone from cyclohexane oxide.

[0007] This invention also provides a method for synthesizing o-chlorocyclohexanone, which utilizes light oil, a byproduct of cyclohexanone production, to prepare o-chlorocyclohexanone. The light oil and a chlorinating agent undergo a ring-opening oxidation reaction at a certain temperature to generate crude o-chlorocyclohexanone. After the reaction, the product is washed with sodium sulfate solution, separated into layers, and purified by oil phase distillation to obtain pure o-chlorocyclohexanone.

[0008] This invention provides a method for preparing a catalyst for the synthesis of o-chlorocyclohexanone. The catalyst consists of a support, a first active component, and a second active component. The active components are loaded in batches to obtain the catalyst, which is used to synthesize o-chlorocyclohexanone from cyclohexanone light raw material.

[0009] Generally, the catalyst preparation steps are as follows:

[0010] (1) The catalyst support is treated in an acid solution, and the first active component with a mass fraction of 5%~30% is added. Under the conditions of water bath at 60℃-90℃, it is ultrasonically dispersed for 1-4 h, kept warm and aged, washed with water until neutral, and dried at low temperature as a catalyst precursor.

[0011] (2) After dissolving the second active component in an ethanol solution, add it to the catalyst precursor, stir and let stand, then calcine it in nitrogen for 2-6 hours to obtain the catalyst.

[0012] Furthermore, the first active component is at least one of sodium chloride, magnesium chloride, calcium chloride, and potassium chloride.

[0013] The acid mentioned is one of nitric acid, sulfuric acid, or hydrochloric acid.

[0014] The second active component is cerium ammonium nitrate and cerium nitrate; the mass content of cerium in the catalyst is 0.01-5%; the ratio of cerium ammonium nitrate to cerium nitrate is 5:1-1:5.

[0015] The low-temperature drying temperature is 60℃-90℃, and the treatment temperature in nitrogen is 200-250℃.

[0016] The carrier is activated carbon or molecular sieve; the molecular sieve is MCM-41, ZSM-5, SAPO-34, or MOR, with MCM-41 being preferred.

[0017] The present invention provides a method for synthesizing o-chlorocyclohexanone: o-chlorocyclohexanone is obtained by reacting cyclohexanone light oil and catalyst under stirring by adding a chlorinating agent dropwise.

[0018] The specific reaction steps are as follows: cyclohexanone light oil and catalyst react with chlorinating agent dropwise under stirring; after the reaction is completed, the mixture is allowed to stand and separate into layers, the lower aqueous phase is filtered, the catalyst is recycled, the upper oil phase is washed with Na2CO3 aqueous solution, and the oil phase is distilled under normal pressure, collecting the fraction between 203 and 204℃. After obtaining crude o-chlorocyclohexanone, it is washed with sodium carbonate solution, separated into layers, and the oil phase is distilled to obtain pure o-chlorocyclohexanone.

[0019] Generally, the cyclohexanone light oil contains cyclohexane oxide, n-pentanol, cyclohexanol, and cyclohexanone; the chlorinating agent is one or a mixture of hydrochloric acid and two of chloric acid, chlorite, and hypochlorous acid; the mass content of hydrochloric acid in the chlorinating agent is 30%-80%.

[0020] The ring-opening reaction temperature is 20℃-50℃, the molar ratio of cyclohexane oxide in the light oil to the chlorinating agent is 1:1-1.5, and the amount of catalyst added is 0.5%-5% of the cyclohexane oxide in the light oil.

[0021] Furthermore, in the synthesis method described above, the catalyst used is the catalyst prepared according to the present invention, preferably Ce-MCM-41.

[0022] Compared with existing technologies, the advantages of the method of this invention are: 1) It synthesizes a batch-supported cerium catalyst with a simple preparation process, which can effectively catalyze the one-step synthesis of o-chlorocyclohexanone from cyclohexane oxide; 2) It utilizes the resource advantage of cyclohexane oxide in light oil, and effectively improves the selectivity and conversion rate of the ring-opening reaction by adding catalysts and chlorinating agents; 3) It is a simple one-step synthesis of o-chlorocyclohexanone with high selectivity and high yield. Implementation

[0023] The present invention will now be described in detail with reference to the embodiments. Example 1

[0024] Catalyst preparation:

[0025] (1) Boil 50g of MCM-41 support in 5% hydrochloric acid solution and reflux for 1h, add 30% sodium chloride, and ultrasonically disperse for 2h under water bath at 60 ℃, turn off the ultrasonic treatment, keep warm for 6h, wash with water until neutral, and dry at 80℃ as catalyst precursor.

[0026] (2) Dissolve 3 g of cerium nitrate and 2 g of cerium ammonium nitrate in 100 mL of 20% ethanol solution, then add them directly to the catalyst precursor. Stir for 3 h, let stand for 5 h, treat in nitrogen at 250 °C for 2 h, and then calcine at 250 °C to obtain Ce-MCM-41 catalyst.

[0027] Synthesis of o-chlorocyclohexanone:

[0028] 200g of light oil (containing 40.6% cyclohexane oxide by weight) and 1g of catalyst Ce-MCM-41 were added to a 500ml four-necked flask. Under stirring, a mixture of 24g of 36% hydrochloric acid and 31g of sodium hypochlorite was added dropwise to initiate the reaction. The reaction temperature was controlled at approximately 30℃, and the reaction time was 1.5 hours. After the reaction, the mixture was allowed to stand and separate into layers. The lower aqueous phase was filtered, and the catalyst was recycled. The upper oil phase was washed three times with 100mL of 10% Na2CO3 aqueous solution. The oil phase was then subjected to atmospheric distillation, and the fraction collected between 203 and 204℃ yielded 103.6g of the product. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 98.7%, and the yield of o-chlorocyclohexanone was 92.9%. Example 2

[0029] Catalyst preparation:

[0030] (1) Boil 50g of MCM-41 support in 5% nitric acid solution and reflux for 1h, add 30% magnesium chloride solution, and ultrasonically disperse for 4h under water bath at 90 ℃, turn off the ultrasonic treatment, keep warm for 2h, wash with water until neutral, and dry at 60℃ as catalyst precursor.

[0031] (2) Dissolve 0.9 g of cerium nitrate and 4.5 g of cerium ammonium nitrate in 100 mL of 20% ethanol solution, then add directly to the catalyst precursor. Stir for 5 h, let stand for 10 h, treat in nitrogen at 200 °C for 6 h, and then calcine at 200 °C to obtain Ce-MCM-41 catalyst.

[0032] Synthesis of o-chlorocyclohexanone:

[0033] Using the same synthesis method as in Example 1, 104.4 g of product was obtained. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 98.3% and the o-chlorocyclohexanone yield was 93.3%. Example 3

[0034] Catalyst preparation:

[0035] (1) Boil 100g of MCM-41 support in 5% nitric acid solution and reflux for 1h, add 5% sodium chloride solution, and ultrasonically disperse for 1h under water bath at 70 ℃, turn off the ultrasonic treatment, keep warm for 2h, wash with water until neutral, and dry at 70℃ as catalyst precursor.

[0036] (2) Dissolve 4.5 g of cerium nitrate and 0.9 g of cerium ammonium nitrate in 100 mL of 20% ethanol solution, then add directly to the catalyst precursor, stir for 5 h, let stand for 5 h, treat in nitrogen at 220 °C for 2 h, and then calcine at 200 °C to obtain Ce-MCM-41 catalyst.

[0037] Synthesis of o-chlorocyclohexanone:

[0038] Using the same synthesis method as in Example 1, 102.6 g of product was obtained. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 98.7% and the o-chlorocyclohexanone yield was 92.0%. Example 4

[0039] Catalyst preparation:

[0040] (1) Boil 100g of MCM-41 support in 20% nitric acid solution and reflux for 2h, add 30% calcium chloride solution, and ultrasonically disperse for 2h under water bath at 70 ℃. Turn off the ultrasonic treatment, keep warm for 2h, wash with water until neutral, and dry at 70℃ as catalyst precursor.

[0041] (2) Dissolve 4 g of cerium nitrate and 1 g of cerium ammonium nitrate in 100 mL of 20% ethanol solution, then add them directly to the catalyst precursor. Stir for 3 h, let stand for 3 h, treat in nitrogen at 220 °C for 2 h, and then calcine at 200 °C to obtain Ce-MCM-41 catalyst.

[0042] Synthesis of o-chlorocyclohexanone:

[0043] Using the same synthesis method as in Example 1, 103.1 g of product was obtained. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 98.5% and the o-chlorocyclohexanone yield was 92.3%. Example 5

[0044] Catalyst preparation:

[0045] (1) Boil 100g of ZSM-5 support in 10% sulfuric acid solution and reflux for 2h, add 20% potassium chloride solution, and ultrasonically disperse for 1h in a water bath at 60 ℃. Turn off the ultrasonic treatment, keep warm for 2h, wash with water until neutral, and dry at 70℃ as a catalyst precursor.

[0046] (2) Dissolve 1 g of cerium nitrate and 4 g of cerium ammonium nitrate in 100 mL of 20% ethanol solution, then add them directly to the catalyst precursor. Stir for 3 h, let stand for 3 h, treat in nitrogen at 220 °C for 2 h, and then calcine at 200 °C to obtain Ce-ZSM-5 catalyst.

[0047] Synthesis of o-chlorocyclohexanone:

[0048] Using the same synthesis method as in Example 1, 103.5g of product was obtained. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 98.1% and the o-chlorocyclohexanone yield was 92.3%. Example 6

[0049] Catalyst preparation:

[0050] (1) Boil 100g of ZSM-5 support in 20% sulfuric acid solution and reflux for 2h, add 20% sodium chloride solution, and ultrasonically disperse for 1h in a water bath at 60 ℃. Turn off the ultrasonic treatment, keep warm for 2h, wash with water until neutral, and dry at 70℃ as a catalyst precursor.

[0051] (2) Dissolve 2 g of cerium nitrate and 3 g of cerium ammonium nitrate in 100 mL of 20% ethanol solution, then add them directly to the catalyst precursor. Stir for 3 h, let stand for 3 h, treat in nitrogen at 220 °C for 2 h, and then calcine at 200 °C to obtain Ce-ZSM-5 catalyst.

[0052] Synthesis of o-chlorocyclohexanone:

[0053] Using the same synthesis method as in Example 1, 103.8g of the product was obtained. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 98.2% and the o-chlorocyclohexanone yield was 92.7%. Example 7

[0054] Catalyst preparation:

[0055] (1) Boil 100g of MCM-41 support in 10% nitric acid solution and reflux for 2h, add 20% sodium chloride solution, and ultrasonically disperse for 1h in a water bath at 60 ℃. Turn off the ultrasonic treatment, keep warm for 2h, wash with water until neutral, and dry at 70℃ as a catalyst precursor.

[0056] (2) Dissolve 2.5 g of cerium nitrate and 2.5 g of cerium ammonium nitrate in 100 mL of 20% ethanol solution, then add them directly to the catalyst precursor. Stir for 1 h, let stand for 4 h, treat in nitrogen at 200 °C for 3 h, and then calcine at 200 °C to obtain Ce-MCM-41 catalyst.

[0057] Synthesis of o-chlorocyclohexanone:

[0058] Using the same synthesis method as in Example 1, 103.3g of the product was obtained. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 98.2% and the o-chlorocyclohexanone yield was 93.2%.

[0059] Comparative Example 1:

[0060] Catalyst preparation:

[0061] (1) Boil 50g of MCM-41 support in 5% hydrochloric acid solution and reflux for 1h, add 30% sodium chloride, keep warm in water bath at 60 ℃ for 6h, wash with water until neutral, and dry at 80℃ as catalyst precursor.

[0062] (2) Dissolve 3 g of cerium nitrate and 2 g of cerium ammonium nitrate in 100 mL of 20% ethanol solution, then add them directly to the catalyst precursor. Stir for 3 h, let stand for 5 h, treat in nitrogen at 250 °C for 2 h, and then calcine at 250 °C to obtain Ce-MCM-41 catalyst.

[0063] Synthesis of o-chlorocyclohexanone:

[0064] Using the same synthesis method as in Example 1, 100.9g of product was obtained. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 97.5% and the o-chlorocyclohexanone yield was 89.4%.

[0065] Comparative Example 2:

[0066] Catalyst preparation:

[0067] (1) Boil 50g of MCM-41 support in 5% hydrochloric acid solution and reflux for 1h, add 30% sodium chloride, and ultrasonically disperse for 2h under water bath at 60 ℃, turn off the ultrasonic treatment, keep warm for 6h, wash with water until neutral, and dry at 80℃ as catalyst precursor.

[0068] (2) Dissolve 5g of cerium nitrate in 100mL of 20% ethanol solution and add it directly to the catalyst precursor. Stir for 3 hours and let stand for 5 hours. Then treat it in nitrogen at 250℃ for 2 hours and calcine it to obtain Ce-MCM-41 catalyst.

[0069] Synthesis of o-chlorocyclohexanone:

[0070] Using the same synthesis method as in Example 1, 102.2 g of product was obtained. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 98.1% and the o-chlorocyclohexanone yield was 91.1%.

[0071] Comparative Example 3:

[0072] Catalyst preparation:

[0073] (1) Boil 50g of MCM-41 support in 5% hydrochloric acid solution and reflux for 1h as a catalyst precursor;

[0074] (2) Dissolve 3 g of cerium nitrate and 2 g of cerium ammonium nitrate in 100 mL of 20% ethanol solution, then add them directly to the catalyst precursor. Stir for 3 h, let stand for 5 h, treat in nitrogen at 250 °C for 2 h, and then calcine at 250 °C to obtain Ce-MCM-41 catalyst.

[0075] Synthesis of o-chlorocyclohexanone:

[0076] Using the same synthesis method as in Example 1, 99.5g of the product was obtained. Gas chromatography analysis showed that the o-chlorocyclohexanone content was 98.2% and the o-chlorocyclohexanone yield was 88.8%.

Claims

1. A method for synthesizing o-chlorocyclohexanone, characterized in that... Cyclohexanone light oil and a catalyst react under stirring conditions by dropwise addition of a chlorinating agent to obtain o-chlorocyclohexanone. The catalyst consists of a support, a first active component, and a second active component. The active components are obtained by batch loading of the catalyst. The first active component is at least one of sodium chloride, magnesium chloride, calcium chloride, and potassium chloride. The second active component is cerium ammonium nitrate and cerium nitrate. The mass content of cerium in the catalyst is 0.01-5%. The ratio of cerium ammonium nitrate to cerium nitrate is 5:1-1:

5.

2. The synthesis method according to claim 1, characterized in that... The catalyst preparation steps are as follows: (1) The catalyst support is treated in an acid solution, and the first active component with a mass fraction of 5%~30% is added. Under the conditions of water bath at 60℃-90℃, it is ultrasonically dispersed for 1-4 h, kept warm and aged, washed with water until neutral, and dried at low temperature as a catalyst precursor. (2) After dissolving the second active component in an ethanol solution, add it to the catalyst precursor, stir and let stand, treat it in nitrogen for 2-6 hours and then calcine to obtain the catalyst.

3. The synthesis method according to claim 2, characterized in that... The acid mentioned is one of nitric acid, sulfuric acid, or hydrochloric acid.

4. The synthesis method according to claim 2, characterized in that... The low-temperature drying temperature is 60℃-90℃, and the treatment temperature in nitrogen is 200-250℃.

5. The synthesis method according to claim 2, characterized in that... The carrier is activated carbon or molecular sieve; the molecular sieve is MCM-41, ZSM-5, SAPO-34, or MOR.

6. The synthesis method according to claim 5, characterized in that... The molecular sieve is of type MCM-41.

7. The synthesis method according to claim 1, characterized in that... The specific reaction steps are as follows: cyclohexanone light oil and catalyst are subjected to a ring-opening reaction by adding chlorinating agent dropwise under stirring. After the reaction is completed, the mixture is allowed to stand and separate into layers. The lower aqueous phase is filtered, the catalyst is recycled, and the upper oil phase is washed with Na2CO3 aqueous solution. The oil phase is then subjected to atmospheric pressure distillation, and the fraction between 203 and 204℃ is collected to obtain crude o-chlorocyclohexanone. After washing with sodium carbonate solution and separating the layers, the oil phase is distilled to obtain pure o-chlorocyclohexanone.

8. The synthesis method according to claim 7, characterized in that... The cyclohexanone light oil contains cyclohexane oxide, n-pentanol, cyclohexanol, and cyclohexanone; the chlorinating agent is one or a mixture of hydrochloric acid and two of chloric acid, chlorite, and hypochlorous acid; the mass content of hydrochloric acid in the chlorinating agent is 30%-80%.

9. The synthesis method according to claim 7, characterized in that... The ring-opening reaction temperature is 20℃-50℃, the molar ratio of cyclohexane oxide in the light oil to the chlorinating agent is 1:1-1.5, and the amount of catalyst added is 0.5%-5% of the cyclohexane oxide in the cyclohexanone light oil.