Method for inhibiting by-product cyclododecane in cyclododecanol hydrogenation preparation process

Abstract

The invention relates to the technical field of cyclododecanol production, in particular to a method for inhibiting by-product cyclododecane in a cyclododecanol hydrogenation preparation process, which comprises the following steps: mixing one or more of cyclododecanone, epoxy cyclododecane or epoxy cyclododecene as raw materials with a solvent to prepare a raw material solution; the raw material liquid is subjected to a hydrogenation reaction, cyclododecanol is prepared, and the water content in the raw material liquid is 3-15 wt%. By adopting the technical scheme provided by the invention, on the premise of not changing the catalyst and the reaction system, the water content in the raw material liquid is controlled to be 3-15wt%, so that the water content of the reaction system in the reaction process is in a proper range, the generation of a byproduct cyclododecane can be effectively inhibited, and the yield of cyclododecanol is obviously improved; and the yield of the byproduct cyclododecane is reduced, so that the heat load of the tower kettle of the light component removal tower can be reduced by 20-50%.

Description

Technical Field

[0001] This invention relates to the field of cyclododecyl alcohol production technology, and specifically to a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol. Background Technology

[0002] Cyclododecyl alcohol (CDOL) is a crucial chemical intermediate in the fragrance and engineering plastics industries. The preparation methods for CDOL mainly fall into two categories: oxidation, typically using cyclododecane as a raw material; and hydrogenation, which can use one or more of the following as raw materials: cyclododecone, epoxide-cyclododecene, epoxide-cyclododecadiene, and epoxide-cyclododecane. Compared to the oxidation method, the hydrogenation method produces CDOL with higher yield, higher purity, and fewer metal impurities.

[0003] For example, patent CN 110882724 A uses polyamide-amine supramolecular grafted modified foam graphene as a carrier and platinum as an active component to selectively hydrogenate 9,10-epoxy-1,5-cyclododecadiene to cyclododecyl alcohol. Although the purity of the obtained cyclododecyl alcohol product is ≥98% and the metal content is <5ppm, a large amount of cyclododecane is still generated in its examples. The byproduct cyclododecane cannot be reused, resulting in significant loss of raw materials and a reduced yield of cyclododecyl alcohol. Summary of the Invention

[0004] Therefore, the purpose of this invention is to reduce the generation of cyclododecane, a byproduct, during the hydrogenation process of cyclododecyl alcohol, thereby providing a method for suppressing cyclododecane, a byproduct, in the hydrogenation process of cyclododecyl alcohol.

[0005] Therefore, this application provides a method for suppressing the byproduct cyclododecane in the hydrogenation preparation process of cyclododecyl alcohol, comprising: using one or more of cyclododecone, cyclododecane oxide or cyclododecene oxide as raw materials and mixing them with a solvent to prepare a raw material liquid; and then taking the raw material liquid for hydrogenation reaction to obtain cyclododecyl alcohol, wherein the water content in the raw material liquid is 3-15 wt%.

[0006] In some embodiments, the epoxycyclododecane includes 1,2-epoxycyclododecane.

[0007] In some embodiments, the epoxy cyclododecene includes one or more of epoxy cyclododecene, epoxy cyclododecadiene, and epoxy cyclododecene polyene.

[0008] In some embodiments, the epoxycyclododecene is selected from one or more of 3,4-epoxycyclododecene, monoepoxycyclododecene, 5,6-epoxycyclododec-1-ene, 9,10-epoxy-1,5-cyclododecadiene, 8,9-epoxy-1,5-cyclododecadiene, and 1,2-epoxycyclododec-4,7,10-triene.

[0009] In some embodiments, the hydrogenation reaction is carried out at a temperature of 50-150°C and a pressure of 8-16 MPaG.

[0010] In some embodiments, the hydrogenation reaction is a batch hydrogenation reaction or a continuous hydrogenation reaction.

[0011] In some embodiments, during the hydrogenation reaction, the feed liquid is placed in a hydrogenation reactor containing a hydrogenation catalyst and then contacted with hydrogen gas to carry out the hydrogenation reaction.

[0012] In some embodiments, during the hydrogenation reaction, the molar ratio of hydrogen to raw materials is 20 to 60:1.

[0013] In some embodiments, the hydrogenation catalyst is selected from one or more of nickel catalysts, cobalt catalysts, palladium catalysts, platinum catalysts, ruthenium catalysts, and rhodium catalysts.

[0014] In some embodiments, the hydrogenation reactor is selected from a batch reactor or a tubular reactor.

[0015] In some embodiments, the water content in the feed liquid is 4-10 wt%.

[0016] In some embodiments, the solvent is a low-carbon alcohol.

[0017] In some embodiments, the mass ratio of the solvent to the raw material in the raw material liquid is 1 to 10:1.

[0018] In some embodiments, the solvent is selected from one or more of methanol, ethanol, and isopropanol.

[0019] In some embodiments, after the hydrogenation reaction is completed, the process further includes solvent removal and distillation to obtain pure cyclododecyl alcohol.

[0020] In some embodiments, after the hydrogenation reaction is completed, the reaction liquid obtained from the hydrogenation reaction is further subjected to desolventizing treatment in a desolventizing column to obtain crude cyclododecyl alcohol product in the bottom of the column, and the solvent is recovered from the top of the column and reused for feed preparation; the crude cyclododecyl alcohol product is fed into a distillation column for distillation, and the cyclododecyl alcohol product is collected from the side stream, and the light components are collected from the top of the column for cyclododecane removal, and the light components after cyclododecane removal are reused for feed preparation.

[0021] In some implementations, the top operating pressure of the desolventizing column is 60 kPaG~70 kPaG, the bottom temperature is 193℃~198℃, and the reflux ratio is 0.3~0.7.

[0022] In some implementations, the operating pressure at the top of the distillation column is -75 kPaG to -55 kPaG, and the bottom temperature is 142°C to 160°C.

[0023] In some implementations, the light component is fed into a light removal tower for cyclododecane removal.

[0024] In some implementations, the operating pressure at the top of the light-weight removal tower is -100 kPaG to -96 kPaG, and the bottom temperature is 130 to 134°C.

[0025] The technical solution of this invention has the following advantages: 1. The method for suppressing the byproduct cyclododecane in the hydrogenation preparation process of cyclododecyl alcohol provided by the present invention includes: using one or more of cyclododecone, cyclododecane oxide or cyclododecene oxide as raw materials and mixing them with a solvent to prepare a raw material liquid; then taking the raw material liquid and performing a hydrogenation reaction to obtain cyclododecyl alcohol; wherein the water content in the raw material liquid is 3-15 wt%.

[0026] Through long-term experiments and industrial practice, the researchers of this invention discovered that the raw material loss in the hydrogenation process for preparing cyclododecyl alcohol is primarily due to the byproduct cyclododecane. The generation pathways of cyclododecane can be divided into two types: one involves hydrogenation of the raw material to cyclododecyl alcohol, followed by further hydrogenation to produce cyclododecane; the other involves dehydration of oxygen-containing raw materials, intermediates, or products in the reaction system to produce the corresponding olefin, which is then further hydrogenated in a hydrogenation environment to produce cyclododecane. Both pathways generate water, and an appropriate water content in the reaction system is crucial for suppressing cyclododecane formation. However, considering the hydrophobicity of the raw materials and the hydrophilicity of the catalyst, a high water content in the reaction system reduces the reaction rate of the raw materials, which is detrimental to large-scale industrial production.

[0027] By using the technical solution provided by this invention, without changing the catalyst and reaction system, the water content in the feed liquid is controlled between 3 and 15 wt%, so that the water content in the reaction system is within an appropriate range during the reaction process. This can effectively suppress the generation of the byproduct cyclododecane, resulting in a significant increase in the yield of cyclododecane. Furthermore, due to the reduction in the amount of byproduct cyclododecane, the heat load of the bottom of the light-removal tower can be reduced by 20 to 50%. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a process flow diagram of the method for suppressing the byproduct cyclododecane in the hydrogenation preparation process of cyclododecyl alcohol provided by the present invention. Detailed Implementation

[0030] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0031] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0032] The sources of the main raw materials used in the various embodiments and comparative examples of this invention are as follows: 9,10-Epoxy-1,5-Cyclododecadiene: Purity >99.7wt%, Wanhua Chemical; Cyclododecanone: Purity >99.8%, Wanhua Chemical; 1,2-Epoxycyclododecane, purity >97.0%, Wanhua Chemical; Hydrogenation catalyst A: A platinum-supported catalyst prepared according to the method of Example 1 of CN110882724B; Hydrogenation catalyst B: A platinum-supported catalyst prepared according to the method in Example 2 of CN110882724B.

[0033] The main analytical methods used in the embodiments and comparative examples of this invention are as follows: Gas chromatography analysis: The reaction solution sample was diluted with chromatographic ethanol, shaken thoroughly, and then analyzed by GC on an Agilent 7820 using an HP-5 capillary column (5% Phenyl Methyl Siloxan, 30 m × 0.32 mm × 0.25 µm) and an FID detector. The injection port temperature was 280 °C, the pressure was 8.5868 psi, and the split ratio was 30:1. The detector temperature was 300 °C, the hydrogen flow rate was 30 mL / min, and the column temperature was programmed: initial column temperature 100 °C, held for 3 minutes, increased to 200 °C at 10 °C / min, held for 2 minutes, then increased to 280 °C at 20 °C / min, held for 5 minutes. The column pressure was 8.5868 psi, the flow rate was 1.5 mL / min, and the residence time was 1.6837 minutes. The injection volume was 0.2 µL.

[0034] Example 1 This embodiment provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol. The process flow is as follows: Figure 1 As shown, the specific steps include the following: 1) Batching: The water content of the raw material 9,10-epoxy-1,5-cyclododecadiene is controlled to be less than 100 ppm by distillation. A methanol aqueous solution with a water content of 10 wt% is used as a solvent. The raw material and the methanol aqueous solution are then mixed at a mass ratio of 1:10 to prepare a raw material solution. At this time, the water content of the raw material solution is 9.1 wt%.

[0035] 2) Hydrogenation reaction: The prepared feed solution is passed into a continuous tubular reactor containing 100 mL of hydrogenation catalyst A, with a feed solution mass hourly space velocity (WHSV) of 0.1 h⁻¹. -1 The hydrogenation reaction temperature was 50℃, the reaction pressure was 16 MPaG, and the molar ratio of hydrogen to raw materials was 30:1. After high-pressure hydrogenation, a hydrogenation reaction solution with cyclododecyl alcohol as the main component (excluding solvents methanol and water) was obtained. The selectivity of cyclododecyl alcohol was 99.5%, the selectivity of cyclododecane was 0.3%, and the remainder consisted of trace impurities such as cyclododecone and epoxide cyclododecane.

[0036] 3) Desolventization: The hydrogenation reaction solution is fed into the desolventization tower. The operating conditions of the desolventization tower are: the operating pressure at the top of the tower is 60 kPaG, the temperature at the bottom of the tower is 198℃, and the reflux ratio is 0.5. The solvent methanol aqueous solution and non-condensable hydrogen are obtained at the top of the tower. The solvent methanol aqueous solution is recycled to prepare the feed solution. Before recycling, the water content of the methanol aqueous solution is controlled to 10 wt%. Then, the feed solution is prepared according to step 1) and fed into the continuous tubular reactor.

[0037] 4) Product Refining (Distillation) and Removal of Light Components: The crude cyclododecyl alcohol is obtained from the bottom of the solvent removal column and fed into a product distillation column. Distillation is carried out at a top operating pressure of -75 kPaG and a bottom temperature of 142°C, controlling the methanol content in the bottom feed to be below 20 ppm. A cyclododecyl alcohol product with a purity ≥ 99.3 wt% is collected from the side stream of the distillation column. Meanwhile, light components, mainly composed of cyclododecane, 9,10-epoxy-1,5-cyclododecadiene, 1,2-epoxycyclododecane, and cyclododecone, are distilled off from the top of the distillation column and fed into a light component removal column. Under a top operating pressure of -98 kPaG and a bottom temperature of 132°C, cyclododecane is collected from the top of the light component removal column, while the remaining light components are collected from the bottom and reused to prepare the feed solution. The feed solution is prepared according to step 1) and then fed into a continuous tubular reactor.

[0038] Example 2 This embodiment provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, comprising the following steps: 1) Batching: The water content of the raw material 9,10-epoxy-1,5-cyclododecadiene is controlled to be less than 100 ppm by distillation. An ethanol aqueous solution with a water content of 14 wt% is used as a solvent. The raw material and the solvent ethanol aqueous solution are then mixed at a mass ratio of 3:7 to prepare a raw material solution. At this time, the water content of the raw material solution is 9.8 wt%.

[0039] 2) Hydrogenation reaction: The prepared feed solution is passed into a reaction tube containing 100 mL of hydrogenation catalyst A. The mass hourly space velocity (WHSV) of the feed solution is 0.1 h⁻¹. -1 The hydrogenation reaction was carried out at a temperature of 100℃ and a pressure of 12 MPaG. The molar ratio of hydrogen to raw materials was 60:1. After high-pressure hydrogenation, a hydrogenation reaction solution with cyclododecyl alcohol as the main component (excluding solvents ethanol and water) was obtained. The selectivity of cyclododecyl alcohol was 99.4%, the selectivity of cyclododecane was 0.5%, and the remainder consisted of trace impurities such as cyclododecone and epoxide cyclododecane.

[0040] 3) Solvent removal: The hydrogenation reaction solution is fed into a solvent removal tower. The operating conditions of the solvent removal tower are: the operating pressure at the top of the tower is 60 kPaG, the temperature at the bottom of the tower is 198℃, and the reflux ratio is 0.5. The solvent ethanol aqueous solution and non-condensable hydrogen are obtained at the top of the tower. The solvent ethanol aqueous solution is recycled for the preparation of the feed solution. Before recycling, the water content of the ethanol aqueous solution is controlled to 14 wt%. Then, the feed solution is prepared according to step 1) and fed into a continuous tubular reactor.

[0041] 4) Product Refining (Distillation) and Removal of Light Components: The crude cyclododecyl alcohol is obtained from the bottom of the solvent removal column. This crude product is fed into a product distillation column, where it is distilled at a top operating pressure of -55 kPaG and a bottom temperature of 160°C. The ethanol content in the bottom material is controlled to be below 20 ppm. A cyclododecyl alcohol product with a purity ≥ 99.3 wt% is collected from the side stream of the distillation column. Meanwhile, light components, mainly composed of cyclododecane, 1,2-epoxycyclododecane, cyclododecone, and 9,10-epoxy-1,5-cyclododecadiene, are distilled off from the top of the distillation column and fed into a light component removal column. At a top operating pressure of -98 kPaG and a bottom temperature of 132°C, cyclododecane is collected from the top of the light component removal column, and the remaining light components are collected from the bottom and reused to prepare the feed solution. The feed solution is prepared according to step 1) and then fed into a continuous tubular reactor.

[0042] Example 3 This embodiment provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, comprising the following steps: 1) Batching: The water content of the raw material 9,10-epoxy-1,5-cyclododecadiene is controlled to be less than 100 ppm by distillation. An isopropanol aqueous solution with a water content of 6 wt% is used as a solvent. The raw material and the solvent isopropanol aqueous solution are then mixed at a mass ratio of 1:2 to prepare a raw material solution. At this time, the water content of the raw material solution is 4 wt%.

[0043] 2) Hydrogenation reaction: The prepared feed solution was passed into a reaction tube containing 100 mL of hydrogenation catalyst B. The mass hourly space velocity (WHSV) of the feed solution was 0.1 h⁻¹. -1 The hydrogenation reaction temperature was 150℃, the reaction pressure was 8 MPaG, and the molar ratio of hydrogen to raw materials was 20:1. After high-pressure hydrogenation, a hydrogenation reaction solution with cyclododecyl alcohol as the main component (excluding solvent isopropanol and water) was obtained. The selectivity of cyclododecyl alcohol was 99.3%, the selectivity of cyclododecane was 0.5%, and the remainder consisted of trace impurities such as cyclododecone and epoxide cyclododecane.

[0044] 3) Solvent removal: The hydrogenation reaction solution is fed into a solvent removal tower. The operating conditions of the solvent removal tower are: the operating pressure at the top of the tower is 70 kPaG, the temperature at the bottom of the tower is 193℃, and the reflux ratio is 0.5. The solvent isopropanol aqueous solution and non-condensable hydrogen are obtained at the top of the tower. The solvent isopropanol aqueous solution is recycled for the preparation of the feed solution. Before recycling, the water content of the isopropanol aqueous solution is controlled to 6 wt%. Then, the feed solution is prepared according to step 1) and fed into a continuous tubular reactor.

[0045] 4) Product Refining (Distillation) and Light Component Removal: The crude cyclododecyl alcohol is obtained from the bottom of the solvent removal column and fed into the product distillation column. Distillation is carried out at a top operating pressure of -70 kPaG and a bottom temperature of 145°C, controlling the isopropanol content in the bottom material to be below 20 ppm. Cyclododecyl alcohol with a purity ≥ 99.3 wt% is collected from the side stream of the distillation column. Meanwhile, light components, mainly composed of cyclododecane, 1,2-epoxycyclododecane, cyclododecone, and 9,10-epoxy-1,5-cyclododecadiene, are distilled off from the top of the product distillation column and fed into the light component removal column. Cyclododecane is collected from the top of the light component removal column at a top operating pressure of -98 kPaG and a bottom temperature of 132°C. The remaining light components are collected from the bottom and reused to prepare the feed solution. The feed solution is prepared according to step 1) and fed into a continuous tubular reactor.

[0046] Example 4 This embodiment provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, which is basically the same as that in Example 1, except that the raw material cyclododecylone is used instead of 9,10-epoxy-1,5-cyclododecadiene. In step 1), during the batching process, the water content of the raw material cyclododecylone is controlled to be less than 100 ppm by distillation.

[0047] Example 5 This embodiment provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, which is basically the same as that in Example 1, except that 1,2-epoxycyclododecane is used instead of 9,10-epoxy-1,5-cyclododecadiene. In step 1), during the batching process, the water content of 1,2-epoxycyclododecane is controlled to be less than 100 ppm by distillation.

[0048] Example 6 This embodiment provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, which is basically the same as that in Example 1. The only difference is that in step 1) ingredient preparation and step 3) solvent recycling, a methanol aqueous solution with a water content of 12wt% is used as the solvent. Then, the raw materials and the methanol aqueous solution are mixed at a mass ratio of 1:10 to prepare a raw material solution. At this time, the water content of the raw material solution is 10.9wt%.

[0049] Example 7 This embodiment provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, which is basically the same as that in Example 1. The only difference is that in step 1) ingredient preparation and step 3) solvent recycling, a methanol aqueous solution with a water content of 3.5 wt% is used as the solvent. Then, the raw materials and the methanol aqueous solution are mixed at a mass ratio of 1:10 to prepare a raw material solution. At this time, the water content of the raw material solution is 3.2 wt%.

[0050] Comparative Example 1 This comparative example provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, which is basically the same as Example 1, except that in step 1) ingredient preparation and step 3) solvent recycling, a methanol aqueous solution with a water content of 0.8 wt% is used as the solvent, and then the raw materials and the methanol aqueous solution are prepared into a raw material liquid at a mass ratio of 1:10. At this time, the water content of the raw material liquid is 0.73 wt%.

[0051] Comparative Example 2 This comparative example provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, which is basically the same as Example 2, except that in step 1) ingredient preparation and step 3) solvent recycling, an ethanol aqueous solution with a water content of 4wt% is used as the solvent, and then the raw materials and the solvent ethanol aqueous solution are prepared into a raw material liquid at a mass ratio of 3:7. At this time, the water content of the raw material liquid is 2.8wt%.

[0052] Comparative Example 3 This comparative example provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, which is basically the same as Example 3, except that in step 1) ingredient preparation and step 3) solvent recycling, an isopropanol aqueous solution with a water content of 24wt% is used as the solvent, and then the raw materials and the solvent isopropanol aqueous solution are prepared into a raw material liquid at a mass ratio of 1:2. At this time, the water content of the raw material liquid is 16wt%.

[0053] Comparative Example 4 This comparative example provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, which is basically the same as Example 4, except that in step 1) ingredient preparation and step 3) solvent recycling, a methanol aqueous solution with a water content of 0.8 wt% is used as the solvent, and then the raw materials and the methanol aqueous solution are prepared into a raw material liquid at a mass ratio of 1:10. At this time, the water content of the raw material liquid is 0.73 wt%.

[0054] Comparative Example 5 This comparative example provides a method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, which is basically the same as Example 5, except that in step 1) ingredient preparation and step 3) solvent recycling, a methanol aqueous solution with a water content of 0.8 wt% is used as the solvent, and then the raw materials and the methanol aqueous solution are prepared into a raw material liquid at a mass ratio of 1:10. At this time, the water content of the raw material liquid is 0.73 wt%.

[0055] Test Example 1 After the hydrogenation reactions in each embodiment and comparative example were stably run for 100 hours, the hydrogenation reaction solution was taken for analysis and testing. The selectivity of cyclododecane, the selectivity of cyclododecane, the yield of cyclododecane, and the feedstock consumption were calculated. Feedstock consumption = feedstock consumption (t) / cyclododecane production (t).

[0056] The purity of the cyclododecyl alcohol product obtained from the distillation column side stream in each embodiment and comparative example preparation process is shown in Table 1.

[0057] Taking the annual production of 50,000 tons of cyclododecyl alcohol as an example, the top of the light-light removal tower is cooled by circulating water, while the bottom of the tower is heated by steam. The heat load of the bottom of the light-light removal tower is shown in Table 1.

[0058] Table 1 Test Results

[0059] Compared to the comparative examples, the production methods provided in the embodiments of this application can significantly reduce the selectivity of cyclododecane, thereby reducing the raw material consumption and the heat load of the light removal tower bottom, and improving the selectivity and yield of cyclododecane. When using 9,10-epoxy-1,5-cyclododecanediene as the reaction raw material, the raw material consumption of Examples 1-3 and Examples 6-7 of this application is significantly reduced compared to Comparative Examples 1-3. When using cyclododecone as the raw material, the raw material consumption of Example 4 of this application is significantly reduced compared to Comparative Example 4. When using 1,2-epoxycyclododecane as the raw material, the raw material consumption of Example 5 of this application is significantly reduced compared to Comparative Example 5.

[0060] A comparison of Examples 1, 4, and 5 shows that Example 1, by using 9,10-epoxy-1,5-cyclododecadiene as a raw material in conjunction with the process method of this application, can further reduce the raw material consumption and the selectivity of cyclododecane, and further reduce the heat load of the light-removal tower bottom.

[0061] A comparison of Examples 1, 6, and 7 shows that Example 1, by controlling the water content in the feed liquid to 4-10 wt%, can further reduce the feed consumption per unit and the selectivity of cyclododecane, and further reduce the heat load of the light-light-removal tower.

[0062] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol, characterized in that, This includes preparing a raw material solution by mixing one or more of cyclododecanone, cyclododecane, or cyclododecene as raw materials with a solvent, and then subjecting the raw material solution to a hydrogenation reaction to obtain cyclododecyl alcohol, wherein the water content in the raw material solution is 3-15 wt%.

2. The method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol according to claim 1, characterized in that, The epoxy cyclododecane includes 1,2-epoxy cyclododecane; And / or, the epoxy cyclododecene includes one or more of epoxy cyclododecene, epoxy cyclododecadiene, and epoxy cyclododecene polyene.

3. The method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol according to claim 2, characterized in that, The epoxy cyclododecene is selected from one or more of 3,4-epoxy cyclododecene, monoepoxy cyclododecene, 5,6-epoxy cyclododec-1-ene, 9,10-epoxy-1,5-cyclododecadiene, 8,9-epoxy-1,5-cyclododecadiene, and 1,2-epoxy cyclododec-4,7,10-triene.

4. The method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol according to any one of claims 1-3, characterized in that, During the hydrogenation reaction, the reaction temperature is 50~150℃ and the reaction pressure is 8~16 MPaG; and / or, the hydrogenation reaction is a batch hydrogenation reaction or a continuous hydrogenation reaction.

5. The method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol according to any one of claims 1-3, characterized in that, In the hydrogenation reaction process, the feed liquid is placed in a hydrogenation reactor containing a hydrogenation catalyst and then comes into contact with hydrogen gas to carry out the hydrogenation reaction.

6. The method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol according to claim 5, characterized in that, In the hydrogenation reaction process, the molar ratio of hydrogen to raw material is 20-60:1; and / or, the hydrogenation catalyst is selected from one or more of nickel catalyst, cobalt catalyst, palladium catalyst, platinum catalyst, ruthenium catalyst, and rhodium catalyst; and / or, the hydrogenation reactor is selected from a batch reactor or a tubular reactor.

7. The method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol according to any one of claims 1-3, characterized in that, The water content in the raw material liquid is 4~10wt%; and / or, the solvent is a low-carbon alcohol; and / or, the mass ratio of the solvent to the raw material in the raw material liquid is 1~10:

1.

8. The method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol according to claim 7, characterized in that, The solvent is selected from one or more of methanol, ethanol, and isopropanol.

9. The method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol according to any one of claims 1-3, characterized in that, After the hydrogenation reaction is completed, the process also includes solvent removal and distillation to obtain pure cyclododecyl alcohol.

10. The method for suppressing the byproduct cyclododecane in the hydrogenation process of cyclododecyl alcohol according to claim 9, characterized in that, After the hydrogenation reaction is completed, the reaction liquid obtained from the hydrogenation reaction is desolventized in a desolventizing tower to obtain crude cyclododecyl alcohol product in the bottom of the tower, and the solvent is recovered from the top of the tower and reused for the preparation of feed liquid. The crude cyclododecyl alcohol product is fed into a distillation tower for distillation, and the cyclododecyl alcohol product is collected from the side stream. The light components are collected from the top of the tower for cyclododecane removal, and the light components after cyclododecane removal are reused for the preparation of feed liquid.

Images