A process for the production of high purity 3-methyl-1-penten-3-ol by a water wash recycling process

Abstract

This invention provides a method for producing high-purity 3-methyl-1-penten-3-ol through a water washing and reuse process. Using 3-methyl-1-pentyn-3-ol as a raw material, partial hydrogenation is performed using a catalyst, controlling the incomplete conversion of the raw material (conversion rate ≤98%) to significantly reduce the formation of the over-hydrogenation byproduct 3-methyl-3-pentanol. Then, the partially hydrogenated reaction solution is treated with water washing to extract the incompletely converted 3-methyl-1-pentyn-3-ol to the aqueous phase, which is then returned to the acetylation process. Finally, the water-washed reaction solution is distilled to obtain high-purity 3-methyl-1-penten-3-ol. This invention is novel in its approach. By controlling the incomplete conversion of the raw material in the partial hydrogenation reaction, the formation of over-hydrogenation byproducts is reduced, thereby improving reaction selectivity and atom utilization. Furthermore, utilizing the slightly water-soluble nature of the reactant 3-methyl-1-pentyn-3-ol, the water washing method achieves a simple and efficient separation of the raw material and product. The separated raw material is directly returned to the acetylation process for recycling, without generating additional waste.

Description

Technical Field

[0001] This invention belongs to the field of fine chemicals, specifically relating to a method for preparing high-purity 3-methyl-1-penten-3-ol from 3-methyl-1-pentyn-3-ol through a three-step process of partial hydrogenation, water washing, and refining. Background Technology

[0002] Ethyl linalool, scientifically known as 3,7-dimethyl-1,6-nonadien-3-ol, is a colorless or pale yellow liquid. Due to its fresh and pleasant floral scent, which is long-lasting and mellow, it is used as a fragrance enhancer in various floral-scented daily chemical products. The consumption of ethyl linalool has been increasing year by year, and its applications are gradually expanding. Besides the traditional rose scent, in recent years ethyl linalool has also been used in the formulation of scents such as lily of the valley, tuberose, lilac, violet, acacia, geranium, and orange blossom. Unlike its analogue linalool, there are currently no reports of sensitization with ethyl linalool, and its addition in downstream products is not restricted. The future prospects of ethyl linalool are continuously viewed favorably. According to current literature reports, the synthesis of ethyl linalool mainly adopts the acetylene route. Butanone and acetylene react to obtain 3-methyl-1-pentyn-3-ol, 3-methyl-1-pentyn-3-ol undergoes partial hydrogenation to obtain 3-methyl-1-penten-3-ol, which is then prepared through rearrangement, acetylation and other reactions.

[0003] The partial hydrogenation of 3-methyl-1-pentyn-3-ol to 3-methyl-1-penten-3-ol is a key reaction in the synthesis of ethyl linalool. Because the boiling points of the feedstock 3-methyl-1-pentyn-3-ol, the over-hydrogenation byproduct 3-methyl-3-pentanol, and the product 3-methyl-1-penten-3-ol are very close, and these two substances will participate in subsequent reactions, generating additional impurities and affecting the aroma of the final product, ethyl linalool, the industry currently commonly uses high-plate distillation columns (30-50 plates) for the purification of 3-methyl-1-penten-3-ol to obtain a high-purity intermediate. However, since 3-methyl-1-penten-3-ol contains an allyl alcohol structure and has poor thermal stability, prolonged bottom retention and high plate numbers cause some distillation degradation, resulting in not only additional product loss but also a reduced distillation yield of 3-methyl-1-penten-3-ol.

[0004] It is well known that a significant portion of the over-hydrogenation product 3-methyl-3-pentanol is obtained by hydrogenating 3-methyl-1-penten-3-ol. If the conversion rate is controlled, leaving a small amount of the feedstock 3-methyl-1-pentyn-3-ol in the reaction system, the catalyst's adsorption of the feedstock is stronger than that of the product, thus reducing the adsorption of the product and consequently decreasing the formation of over-hydrogenation byproducts. However, controlling the presence of a residual feedstock also introduces additional challenges, as the distillation separation of the feedstock and product requires a high number of trays. Consequently, there is currently little exploration and practice in this area within the industry. If a simple, efficient, and low-energy separation of the feedstocks 3-methyl-1-pentyn-3-ol and 3-methyl-1-penten-3-ol can be achieved, the aforementioned method would have significant potential application value and practical significance. Summary of the Invention

[0005] The purpose of this invention is to provide a method for producing high-purity 3-methyl-1-penten-3-ol through a water washing and reuse process. Using 3-methyl-1-pentyn-3-ol as a raw material, partial hydrogenation is performed using a catalyst, controlling incomplete conversion of the raw material (conversion rate ≤97%) to significantly reduce the formation of the over-hydrogenation byproduct 3-methyl-3-pentanol. Then, the partially hydrogenated reaction solution is treated with water washing to extract the incompletely converted 3-methyl-1-pentyn-3-ol into the aqueous phase. Finally, the washed reaction solution is subjected to distillation to obtain high-purity 3-methyl-1-penten-3-ol. This invention achieves a simple, efficient, and low-energy separation of 3-methyl-1-pentyn-3-ol and 3-methyl-1-penten-3-ol, providing a simple and efficient method for the preparation of high-purity 3-methyl-1-penten-3-ol.

[0006] To achieve the above objectives and technical effects, the present invention adopts the following technical solution:

[0007] A method for producing high-purity 3-methyl-1-penten-3-ol via a water washing and reuse process, comprising the following process flow:

[0008] S1, using 3-methyl-1-pentyn-3-ol and hydrogen as raw materials, carries out a hydrogenation reaction using a catalyst, controlling the incomplete conversion of the raw materials to obtain a partially hydrogenated reaction liquid;

[0009] S2, Part of the hydrogenation reaction solution is treated by water washing to obtain a water-washed partial hydrogenation reaction solution;

[0010] S3, high-purity 3-methyl-1-penten-3-ol was obtained by distillation and separation of the water-washed portion of the hydrogenated reaction solution.

[0011] The S1 reaction preferably uses a Lindlar-type catalyst for partial hydrogenation. Preferably, the Lindlar-type catalyst can be one or more of palladium-calcium carbonate, palladium-barium sulfate, palladium-alumina, and palladium-zirconia. Preferably, the palladium loading in the catalyst is 0.5 to 5.0 wt%. The amount of catalyst used is 0.2% to 2.0% of the raw material mass.

[0012] The hydrogenation reaction described in S1 can be carried out in a solvent, preferably without using a solvent. If a solvent is used to dilute the reaction, a low-boiling-point, sparingly soluble, or even insoluble-in-water solvent is preferred, which may be one or more of hexane, heptane, octane, petroleum ether, cyclohexane, methylcyclohexane, toluene, xylene, ethyl acetate, butyl acetate, etc. If a solvent is used, the amount of the solvent is 0.3-3.0 times the mass of the raw material 3-methyl-1-pentyn-3-ol.

[0013] In the S1 hydrogenation reaction, it is preferable to add organophosphorus and inorganic salt auxiliaries. Preferably, the organophosphorus can be one or more of triphenylphosphine, tributylphosphine, tricyclohexylphosphine, tris(2-methylphenyl)phosphine, and tris(4-methylbenzene)phosphine, and the amount of organophosphorus added is 100-300 ppm. The inorganic salt can be one or more of zinc chloride, zinc bromide, zinc acetate, zinc nitrate, and zinc oxalate, and the amount of inorganic salt added is 20-60 ppm. The amounts of organophosphorus and inorganic salt auxiliaries are based on the mass of the raw materials.

[0014] In step S1, one or more methods, including but not limited to monitoring hydrogen consumption, sampling analysis, and online infrared spectroscopy, can be used to detect the hydrogenation reaction process and control incomplete conversion of the raw materials. Preferably, the conversion rate of the raw material 3-methyl-1-pentyn-3-ol is ≤98%, more preferably 90-98%, and even more preferably 96-98%.

[0015] The hydrogenation reaction temperature in S1 is controlled at 30~60℃, preferably 40~60℃; and / or the hydrogen pressure is 0.2~3.0MPaG, preferably 1.0~2.0MPaG.

[0016] The present invention may optionally include a solvent removal process before the S2 water washing treatment of the hydrogenation reaction solution. That is, when the hydrogenation reaction described in step S1 is carried out in a solvent, a solvent removal process is required before the water washing treatment of the hydrogenation reaction solution.

[0017] The solvent removal process includes distillation / evaporation, specifically rotary evaporation, vacuum distillation, etc.

[0018] The water washing temperature in S2 is 30~60℃; the water washing method can be one or more of the following: a phase separation tank with stirring, a sieve plate tower, a rotating disc extraction tower, and a turbine extraction tower.

[0019] In step S2, the water washing uses deionized water or a low-concentration salt solution. Preferably, the salt can be one or more of ammonium acetate, ammonium chloride, ammonium sulfate, ammonium carbonate, ammonium phosphate, and ammonium nitrate. The concentration of the salt solution is preferably 2-5 wt%. The total amount of deionized water or salt solution used for water washing is 30%-60% of the mass of the partial hydrogenation reaction solution obtained in step S1.

[0020] The water washing in S2 is preferably performed multiple times, such as 2-5 times, until the content of 3-methyl-1-pentyn-3-ol in part of the hydrogenation reaction solution drops to 0.1% or below.

[0021] This invention utilizes the different solubilities of the reactant 3-methyl-1-pentyn-3-ol and the product 3-methyl-1-penten-3-ol in water. The reactant 3-methyl-1-pentyn-3-ol is slightly soluble in water, so it remains in the aqueous phase and is sent back to the acetylation process (butanone and acetylene react to obtain 3-methyl-1-pentyn-3-ol). The product 3-methyl-1-penten-3-ol is insoluble in water and remains in the organic phase. Finally, the reaction solution after washing with water is separated by distillation to obtain high-purity 3-methyl-1-penten-3-ol.

[0022] The distillation separation described in this invention includes a product distillation step. Specifically, the product distillation conditions are as follows: 10-15 trays, top temperature of 70-75°C, bottom temperature of 90-100°C, reflux ratio of 1-2:1, top pressure of 15-20 kPa, and a portion of the hydrogenated liquid after water washing is optionally subjected to solvent removal distillation treatment and then continuously fed from the bottom of the column. 3-Methyl-1-penten-3-ol is collected from the top of the column with a purity of 99.5-99.8 wt%.

[0023] The present invention, by adopting the above technical solution, has the following positive effects:

[0024] 1. This invention has a novel approach. By controlling the incomplete conversion of the hydrogenation reaction raw materials, it reduces the generation of excessive hydrogenation byproducts, thereby improving reaction selectivity and atom utilization.

[0025] 2. This invention utilizes the characteristic that the raw materials are slightly soluble in water and the hydrogenation products are insoluble in water, and adopts a water washing method to achieve simple and efficient separation of raw materials and products. The separated raw materials are directly sent back to the acetylation process for recycling and reuse, without generating additional waste.

[0026] 3. Use a low-concentration ammonium salt aqueous solution to wash part of the hydrogenation reaction solution to improve the washing effect; since the acetylation process itself produces ammonium salt, the 3-methyl-1-pentyn-3-ol and ammonium salt aqueous solution obtained from the washing can be directly sent back to the acetylation process for recycling. Detailed Implementation

[0027] The present invention is described in detail below through embodiments, but the present invention is not limited to the embodiments described below.

[0028] The main raw material information is as follows:

[0029] 3-Methyl-1-pentyn-3-ol, Inokai, 99%; 5% palladium-calcium carbonate, 5% palladium-calcium carbonate, 5% palladium-barium sulfate, Johnson Matthey; 2% palladium-alumina, Xinnoco catalyst. Triphenylphosphine, tributylphosphine, tricyclohexylphosphine, Aladdin reagent, 99%; tris(2-methylphenyl)phosphine, tris(4-methylphenyl)phosphine, Alpha reagent, 99%; zinc chloride, zinc acetate, Bailingwei reagent, purity 98-99%; n-hexane, cyclohexane, Sinopharm reagent, chromatographic grade. Zinc bromide, purity 99%, Aladdin reagent. Ammonium acetate, Bailingwei reagent, purity 99%; ammonium sulfate, ammonium chloride, Sinopharm reagent, purity 99%.

[0030] The gas chromatography test conditions of this invention are as follows:

[0031] Instrument model: Agilent 7890B; Column: HP-5 capillary column (30m × 0.30mm × 0.25μm); Initial temperature 50℃, increased to 100℃ at a rate of 10℃ / min; then increased to 200℃ at a rate of 10℃ / min and held for 5 min. Carrier gas: high-purity nitrogen, split ratio 40:1, split flow rate 40 mL / min. Carrier gas saving: 10 mL / min, initial waiting time 3 min. Injection temperature 250℃, detector: FID, detector temperature 250℃, air flow rate 300 mL / min, hydrogen flow rate 30 mL / min, make-up gas flow rate 40 mL / min, injection volume 0.1 μL.

[0032] Example 1

[0033] In air, at room temperature, 300.0 g (3.06 mol) of 3-methyl-1-pentyn-3-ol and 1.5 g (0.5 wt%) of 5% palladium-calcium carbonate catalyst were added to a 500 mL autoclave. After mixing thoroughly, triphenylphosphine (30 mg, 100 ppm relative to the raw material) and zinc chloride (6 mg, 20 ppm relative to the raw material) were added. The autoclave was sealed and carefully and slowly purged with nitrogen three times. Then, the pressure was increased to 2.0 MPaG with nitrogen and maintained for 15 minutes. The pressure drop inside the autoclave was <0.05 MPa, indicating good sealing of the autoclave. The nitrogen in the autoclave was then purged, and the autoclave was purged with high-purity hydrogen (99.9% purity, CO content <50 ppm) three times, each time pressurized to 1.0 MPaG and then vented. Finally, the pressure was increased to 1.0 MPaG with hydrogen. Turn on the high-pressure reactor stirring (600 rpm) and jacket heating, keeping the hydrogen pipeline valve open to stabilize the pressure inside the reactor at 1.0 MPaG. When the reactor temperature reaches 40°C, maintain the temperature and monitor the reaction progress using an online infrared detector. When approximately 3% of the reactant 3-methyl-1-pentyn-3-ol remains, stop the reaction, turn off the stirring, and vent the hydrogen to atmospheric pressure. Sample the reaction solution and perform GC analysis to determine its composition. Correct and normalize the reaction results. The reactant conversion rate is 97.2%, the selectivity of the product 3-methyl-1-penten-3-ol is 99.4%, and the over-hydrogenation byproduct 3-methyl-3-pentanol is 0.3%. Charge the reactor with 0.5 MPaG of nitrogen and filter the reaction liquid through a filter to remove the solid catalyst, obtaining a clear reaction solution, which is then washed with water.

[0034] The obtained reaction solution (293.2 g) was poured into a three-necked flask, followed by 29.3 g (15% of the reaction solution mass) of deionized water. The flask was placed in an oil bath, and once the temperature inside the flask reached 40°C, stirring was started at 600 rpm for 10 minutes. After stirring, the reaction solution was allowed to stand until the oil and water phases separated. The aqueous phase was then drained, and a small amount of the washed reaction solution was analyzed using a dropper to determine the content of 3-methyl-1-pentyn-3-ol in the oil phase. The above operation was repeated twice, keeping the amount of deionized water added, temperature, and stirring speed constant. The analysis results showed that after three washes, the content of 3-methyl-1-pentyn-3-ol in the oil phase had decreased to below 0.1%. The aqueous phase after phase separation can be directly added to the butanone acetylation reaction solution and used as quenching water for the acetylation reaction without affecting the post-treatment of the acetylation reaction. The washed reaction solution was added to a 2L three-necked flask equipped with a magnetic stirrer. A 0.5m long distillation column and reflux ratio controller were connected to the top of the three-necked flask. The column was filled with 3*3 triangular helical packing, and the total number of trays was 15. The three-necked flask was placed in an oil bath, and the oil bath stirring and heating were turned on. The stirring was controlled at 600 rpm, and the oil bath temperature was controlled at 100-110℃, so that the temperature inside the three-necked flask was maintained at 95-100℃. The overhead condensate and vacuum system were turned on, and the condensation temperature was controlled at 5℃, and the overhead pressure was controlled at 20kPa. The overhead temperature was 70-75℃, and the overhead reflux ratio was controlled at 1~2:1. The overhead liquid was sampled periodically and analyzed by GC. The results showed that the purity of the 3-methyl-1-pentyn-3-ol collected from the overhead was on average 99.7%, which met the requirements of subsequent reactions.

[0035] Example 2

[0036] In air, at room temperature, 300.0 g (3.06 mol) of 3-methyl-1-pentyn-3-ol and 0.5% palladium-calcium carbonate catalyst (6.0 g, 2.0 wt%, relative to the raw material) were added to a 500 mL autoclave. After mixing thoroughly, triphenylphosphine (90 mg, 300 ppm relative to the raw material) and zinc chloride (12 mg, 40 ppm relative to the raw material) were added. The autoclave was sealed and carefully and slowly purged with nitrogen three times. Then, the pressure was increased to 2.0 MPaG with nitrogen and maintained for 15 minutes. The pressure drop inside the autoclave was <0.05 MPa, indicating good sealing of the autoclave. The nitrogen in the autoclave was then purged, and the autoclave was purged with high-purity hydrogen (99.9% purity, CO content <50 ppm) three times, each time pressurized to 1.0 MPaG and then vented. Finally, the pressure was increased to 0.2 MPaG with hydrogen. Turn on the high-pressure reactor stirring (600 rpm) and jacket heating, keeping the hydrogen pipeline valve open to stabilize the pressure inside the reactor at 0.2 MPaG. Once the reactor temperature reaches 60°C, maintain the temperature and monitor the reaction progress using an online infrared detector. When approximately 10% of the reactant 3-methyl-1-pentyn-3-ol remains, stop the reaction, turn off the stirring, and vent the hydrogen to atmospheric pressure. Sample the reaction solution and perform GC analysis to determine its composition. Correct and normalize the reaction results. The reactant conversion rate is 90.1%, the selectivity of the product 3-methyl-1-penten-3-ol is 99.7%, and the over-hydrogenation byproduct 3-methyl-3-pentanol is 0.1%. Charge the reactor with 0.5 MPaG of nitrogen and filter the reaction liquid through a filter to remove the solid catalyst, obtaining a clear reaction solution, which is then washed with water.

[0037] The previously obtained reaction solution (292.0 g) was poured into a three-necked flask, followed by the addition of 58.4 g (20% of the reaction solution mass) of ammonium acetate aqueous solution (5% mass concentration). The flask was placed in an oil bath, and once the temperature inside the flask reached 60°C, stirring was started at 600 rpm for 10 minutes. The stirring was then stopped, and the reaction solution was allowed to stand until the oil and water phases were separated. The aqueous phase was then drained, and a small amount of the washed reaction solution was taken dropwise for analysis to determine the content of 3-methyl-1-pentyn-3-ol in the oil phase. The above operation was repeated twice, keeping the amount of ammonium acetate aqueous solution added, temperature, and stirring speed constant. The analysis results showed that after three washes, the content of 3-methyl-1-pentyn-3-ol in the oil phase had decreased to below 0.1%. The washed reaction solution was then added to a 2L three-necked flask equipped with a magnetic stirrer. A 0.3m long distillation column and a reflux ratio controller were connected to the top of the three-necked flask. The column was filled with 3*3 triangular spiral packing, and the total number of trays was 10. The three-necked flask was placed in an oil bath, and the oil bath stirring and heating were turned on. The stirring was controlled at 600 rpm, and the oil bath temperature was controlled at 100-110℃, so that the temperature inside the three-necked flask was maintained at 90-95℃. The overhead condensate and vacuum system were turned on, and the condensation temperature was controlled at 5℃, and the overhead pressure was controlled at 15 kPa. The overhead temperature was 70-73℃, and the overhead reflux ratio was controlled at 1~2:1. The overhead product was sampled periodically and analyzed by GC. The results showed that the 3-methyl-1-pentyn-3-ol collected from the overhead product had an average purity of 99.6%, which met the requirements of subsequent reactions.

[0038] Example 3

[0039] In air, at room temperature, 300.0 g (3.06 mol) of 3-methyl-1-pentyn-3-ol and 1.5 g (0.5 wt%) of 5% palladium-calcium carbonate catalyst were added to a 500 mL autoclave. After mixing thoroughly, tributylphosphine (30 mg, 100 ppm relative to the raw material) and zinc acetate (15 mg, 50 ppm relative to the raw material) were added. The autoclave was sealed and carefully and slowly purged with nitrogen three times. Then, the pressure was increased to 2.0 MPaG with nitrogen and maintained for 15 minutes. The pressure drop inside the autoclave was <0.05 MPa, indicating good sealing of the autoclave. The nitrogen in the autoclave was then purged, and the autoclave was purged with high-purity hydrogen (99.9% purity, CO content <50 ppm) three times, each time pressurized to 1.0 MPaG and then vented. Finally, the pressure was increased to 2.0 MPaG with hydrogen. Turn on the high-pressure reactor stirring (600 rpm) and jacket heating, keeping the hydrogen pipeline valve open to stabilize the pressure inside the reactor at 2.0 MPaG. Once the reactor temperature reaches 30°C, maintain the temperature and monitor the reaction progress using an online infrared detector. When approximately 2% of the reactant 3-methyl-1-pentyn-3-ol remains, stop the reaction, turn off the stirring, and vent the hydrogen to atmospheric pressure. Sample the reaction solution and perform GC analysis to determine its composition. Correct and normalize the reaction results. The reactant conversion rate is 98.0%, the selectivity of the product 3-methyl-1-penten-3-ol is 99.7%, and the over-hydrogenation byproduct 3-methyl-3-pentanol is 0.2%. Charge the reactor with 0.5 MPaG of nitrogen and filter the reaction liquid through a filter to remove the solid catalyst, obtaining a clear reaction solution, which is then washed with water.

[0040] The aforementioned reaction solution (294.0 g) was poured into a three-necked flask, which was then placed in an oil bath. The oil bath was heated until the temperature inside the flask reached 60°C. The 60°C reaction solution was then pumped to the bottom inlet of a micro-rotating disc extraction column using a horizontal flow pump at a feed rate of 3.0 g / min. Simultaneously, a 60°C ammonium acetate aqueous solution (5% by mass concentration) was fed to the top of the disc at a feed rate of 0.9 g / min. The rotating disc extraction column had 5 stages. The washed oil phase was collected in a phase separation tank at the top of the rotating disc column. After all the reaction solution had been fed, a sample was taken to analyze the composition of the organic phase after water washing. Keeping other conditions constant, the ammonium acetate aqueous solution was replaced with deionized water, and the reaction was washed again. Analysis showed that the 3-methyl-1-pentyn-3-ol content in the oil phase after washing with the ammonium acetate aqueous solution had decreased to below 0.1%. The aqueous phase after phase separation in the rotating disc extraction column was directly added to the butanone acetylation reaction solution and used as quenching water for the acetylation reaction. The washed reaction solution was added to a 2L three-necked flask equipped with a magnetic stirrer. A 0.5m long distillation column and reflux ratio controller were connected to the top of the three-necked flask. The column was filled with 3*3 triangular helical packing, and the total number of trays was 15. The three-necked flask was placed in an oil bath, and the oil bath stirring and heating were turned on. The stirring was controlled at 600 rpm, and the oil bath temperature was controlled at 100-120℃, so that the temperature inside the three-necked flask was maintained at 90-100℃. The overhead condensate and vacuum system were turned on, and the condensation temperature was controlled at 5℃, and the overhead pressure was controlled at 20kPa. The overhead temperature was 70-75℃, and the overhead reflux ratio was controlled at 1~2:1. The overhead liquid was sampled periodically and analyzed by GC. The results showed that the purity of the 3-methyl-1-pentyn-3-ol collected from the overhead was 99.9% on average, which met the requirements of subsequent reactions.

[0041] Example 4

[0042] In air, at room temperature, 300.0 g (3.06 mol) of 3-methyl-1-pentyn-3-ol and 0.6 g (0.2 wt%) of 5% palladium-barium sulfate catalyst were added to a 500 mL autoclave. After mixing thoroughly, tricyclohexylphosphine (30 mg, 100 ppm relative to the raw material) and zinc chloride (15 mg, 50 ppm relative to the raw material) were added. The autoclave was sealed and carefully and slowly purged with nitrogen three times. Then, the pressure was increased to 2.0 MPaG with nitrogen and maintained for 15 minutes. The pressure drop inside the autoclave was <0.05 MPa, indicating good sealing of the autoclave. The nitrogen in the autoclave was then purged, and the autoclave was purged with high-purity hydrogen (99.9% purity, CO content <50 ppm) three times, each time pressurized to 1.0 MPaG and then vented. Finally, the pressure was increased to 1.0 MPaG with hydrogen. Turn on the high-pressure reactor stirring (600 rpm) and jacket heating, keeping the hydrogen pipeline valve open to stabilize the pressure inside the reactor at 1.0 MPaG. Once the reactor temperature reaches 50°C, maintain the temperature and monitor the reaction progress using an online infrared detector. When approximately 3% of the reactant 3-methyl-1-pentyn-3-ol remains, stop the reaction, turn off the stirring, and vent the hydrogen to atmospheric pressure. Sample the reaction solution and perform GC analysis to determine its composition. Correct and normalize the reaction results. The reactant conversion rate is 97.1%, the selectivity of the product 3-methyl-1-penten-3-ol is 99.8%, and the over-hydrogenation byproduct 3-methyl-3-pentanol is 0.1%. Charge the reactor with 0.5 MPaG of nitrogen and filter the reaction liquid through a filter to remove the solid catalyst, obtaining a clear reaction solution, which is then washed with water.

[0043] The aforementioned reaction solution (289.6 g) was poured into a three-necked flask, which was then placed in an oil bath. The oil bath was heated until the temperature inside the flask reached 50°C. The 50°C reaction solution was then pumped to the bottom inlet of a micro rotary disc extractor using a horizontal pump at a feed rate of 3.0 g / min. Simultaneously, a 50°C ammonium sulfate aqueous solution (2% by mass concentration) was fed to the top of the disc at a feed rate of 1.8 g / min. The rotary disc extractor had 5 stages. The washed oil phase was collected in a phase separation tank at the top of the disc. After all the reaction solution had been fed, a sample was taken to analyze the composition of the organic phase after water washing. The analysis results showed that the content of 3-methyl-1-pentyn-3-ol in the oil phase after washing with ammonium sulfate aqueous solution had decreased to below 0.1%. The washed reaction solution was added to a 2L three-necked flask equipped with a magnetic stirrer. A 0.5m long distillation column and a reflux ratio controller were connected to the top of the three-necked flask. The column was filled with 3*3 triangular spiral packing, and the total number of trays was 15. The three-necked flask was placed in an oil bath, and the oil bath stirring and heating were turned on. The stirring was controlled at 600 rpm, and the oil bath temperature was controlled at 100-120℃, so that the temperature inside the three-necked flask was maintained at 90-100℃. The overhead condensate and vacuum system were turned on, and the condensation temperature was controlled at 5℃, and the overhead pressure was controlled at 20kPa. The overhead temperature was 70-75℃, and the overhead reflux ratio was controlled at 1~2:1. The overhead liquid was sampled periodically and analyzed by GC. The results showed that the purity of the 3-methyl-1-pentyn-3-ol collected from the overhead was 99.8% on average, which met the requirements of subsequent reactions.

[0044] Example 5

[0045] In air, at room temperature, add 300.0 g (3.06 mol) of 3-methyl-1-pentyn-3-ol, 2% palladium-alumina catalyst (3.0 g, 1.0 wt%, lead poisoning relative to the raw material), and 900.0 g of hexane solvent to a 2 L autoclave. After mixing thoroughly, add 30 mg (100 ppm relative to the raw material) of tris(2-methylphenyl)phosphine and 15 mg (50 ppm relative to the raw material) of zinc bromide. Seal the autoclave and carefully and slowly purge it with nitrogen three times. Then pressurize with nitrogen to 2.0 MPaG and hold the pressure for 15 minutes. The pressure drop inside the autoclave is <0.05 MPa, indicating good sealing of the autoclave. Purge the nitrogen from the autoclave and purge it with high-purity hydrogen (99.9% purity, CO content <50 ppm) three times, pressurizing to 1.0 MPaG each time and then venting. Finally, pressurize with hydrogen to 1.5 MPaG. Turn on the high-pressure reactor stirring (600 rpm) and jacket heating, keeping the hydrogen pipeline valve open to stabilize the pressure inside the reactor at 1.5 MPaG. When the reactor temperature reaches 60°C, maintain the temperature and monitor the reaction progress using an online infrared detector. When approximately 4% of the reactant 3-methyl-1-pentyn-3-ol remains, stop the reaction, turn off the stirring, and vent the hydrogen to atmospheric pressure. Sample the reaction solution and perform GC analysis to determine its composition. Correct and normalize the reaction results. The reactant conversion rate is 96.4%, the selectivity of the product 3-methyl-1-penten-3-ol is 99.7%, and the over-hydrogenation byproduct 3-methyl-3-pentanol is 0.2%. Charge the reactor with 0.5 MPaG of nitrogen and filter the reaction liquid through a filter to remove the solid catalyst, obtaining a clear reaction solution. Use a rotary evaporator to remove the solvent from the resulting reaction solution (3 kPa, 30°C). The crude product obtained after solvent removal is then washed with water for further processing.

[0046] The aforementioned reaction solution (362.6 g) was poured into a three-necked flask, which was then placed in an oil bath. The oil bath was heated until the temperature inside the flask reached 40°C. The 40°C reaction solution was then pumped to the bottom inlet of a micro-rotating disc extraction column using a horizontal flow pump at a feed rate of 4.0 g / min. Simultaneously, a 40°C ammonium sulfate aqueous solution (5% by mass concentration) was fed to the top of the disc at a feed rate of 2.0 g / min. The rotating disc extraction column had 5 stages. The washed oil phase was collected in a phase separation tank at the top of the rotating disc column. After all the reaction solution had been completely fed, a sample was taken to analyze the composition of the organic phase after water washing. Keeping other conditions constant, the ammonium sulfate aqueous solution was replaced with deionized water, and the reaction was washed again. The analysis results showed that the content of 3-methyl-1-pentyn-3-ol in the oil phase after washing with ammonium sulfate aqueous solution had decreased to below 0.1%. The washed reaction solution was added to a 2L three-necked flask equipped with a magnetic stirrer. A 0.5m long distillation column and a reflux ratio controller were connected to the top of the three-necked flask. The column was filled with 3*3 triangular spiral packing, and the total number of trays was 15. The three-necked flask was placed in an oil bath, and the oil bath stirring and heating were turned on. The stirring was controlled at 600 rpm, and the oil bath temperature was controlled at 100-120℃, so that the temperature inside the three-necked flask was maintained at 90-100℃. The overhead condensate and vacuum system were turned on, and the condensation temperature was controlled at 5℃, and the overhead pressure was controlled at 20kPa. The overhead temperature was 70-75℃, and the overhead reflux ratio was controlled at 1~2:1. The overhead liquid was sampled periodically and analyzed by GC. The results showed that the purity of the 3-methyl-1-pentyn-3-ol collected from the overhead was 99.8% on average, which met the requirements of subsequent reactions.

[0047] Example 6

[0048] In air, at room temperature, add 300.0 g (3.06 mol) of 3-methyl-1-pentyn-3-ol, 1.5 g (0.5 wt%) of 5% palladium-calcium carbonate catalyst, and 90 g of cyclohexane solvent to a 1 L autoclave. Mix the three components thoroughly, then add 60 mg (200 ppm) of tris(4-methylphenyl)phosphine and 15 mg (50 ppm) of zinc chloride. Seal the autoclave and carefully and slowly purge it with nitrogen three times. Then pressurize with nitrogen to 2.0 MPaG and hold the pressure for 15 minutes. The pressure drop inside the autoclave should be <0.05 MPa, indicating good sealing of the autoclave. Purge the nitrogen from the autoclave and purge it with high-purity hydrogen (99.9% purity, CO content <50 ppm) three times, pressurizing to 1.0 MPaG each time and then venting. Finally, pressurize with hydrogen to 1.5 MPaG. Turn on the high-pressure reactor stirring (600 rpm) and jacket heating, keeping the hydrogen pipeline valve open to stabilize the pressure inside the reactor at 1.5 MPaG. When the reactor temperature reaches 50°C, maintain the temperature and monitor the reaction progress using an online infrared detector. When approximately 3% of the reactant 3-methyl-1-pentyn-3-ol remains, stop the reaction, turn off the stirring, and vent the hydrogen to atmospheric pressure. Sample the reaction solution and perform GC analysis to determine its composition. Correct and normalize the reaction results. The reactant conversion rate is 97.2%, the product 3-methyl-1-penten-3-ol selectivity is 99.8%, and the over-hydrogenation byproduct 3-methyl-3-pentanol is 0.2%. Charge the reactor with 0.5 MPaG of nitrogen and filter the reaction liquid through a filter to remove the solid catalyst, obtaining a clear reaction solution. Use a rotary evaporator to remove the solvent from the resulting reaction solution (3 kPa, 30°C). The crude product obtained after solvent removal is then washed with water.

[0049] The aforementioned reaction solution (380g) was poured into a three-necked flask, which was then placed in an oil bath. The oil bath was heated until the temperature inside the flask reached 50°C. The 50°C reaction solution was then pumped to the bottom inlet of a micro-turbine extraction column using a horizontal flow pump at a feed rate of 2.0g / min. Simultaneously, a 50°C ammonium chloride aqueous solution (5% by mass concentration) was fed to the top of the rotating disc at a feed rate of 1.0g / min. The rotating disc extraction column had four stages. The washed oil phase was collected in a phase separation tank at the top of the rotating disc column. After all the reaction solution had been completely fed, a sample was taken to analyze the composition of the organic phase after water washing. Keeping other conditions constant, the ammonium chloride aqueous solution was replaced with deionized water, and the reaction was washed again. The analytical results showed that the content of 3-methyl-1-pentyn-3-ol in the oil phase after washing with ammonium chloride aqueous solution had decreased to below 0.1%. The washed reaction solution was added to a 2L three-necked flask equipped with a magnetic stirrer. A 0.5m long distillation column and a reflux ratio controller were connected to the top of the three-necked flask. The column was filled with 3*3 triangular spiral packing, and the total number of trays was 15. The three-necked flask was placed in an oil bath, and the oil bath stirring and heating were turned on. The stirring was controlled at 600 rpm, and the oil bath temperature was controlled at 100-120℃, so that the temperature inside the three-necked flask was maintained at 90-100℃. The overhead condensate and vacuum system were turned on, and the condensate temperature was controlled at 5℃, the overhead pressure was controlled at 15kPa, the bottom temperature was 90-100℃, the top temperature was 70-75℃, and the overhead reflux ratio was controlled at 1~2:1. The product 3-methyl-1-pentyn-3-ol was collected. The overhead product was sampled periodically and analyzed by GC. The results showed that the purity of the 3-methyl-1-pentyn-3-ol collected from the top of the column was 99.8% on average, which met the requirements of subsequent reactions.

Claims

1. A method for producing high-purity 3-methyl-1-penten-3-ol via a water washing and reuse process, characterized in that, Includes the following steps: S1, using 3-methyl-1-pentyn-3-ol and hydrogen as raw materials, hydrogenation is carried out using a catalyst, and the conversion rate of the raw material 3-methyl-1-pentyn-3-ol is controlled to be ≤98%, to obtain a partially hydrogenated reaction solution; S2, Part of the hydrogenation reaction solution is treated by water washing to obtain a water-washed partial hydrogenation reaction solution; S3, high-purity 3-methyl-1-penten-3-ol was obtained by distillation and separation of the water-washed portion of the hydrogenated reaction solution.

2. The method according to claim 1, characterized in that, The S1 uses a Lindlar-type catalyst, including one or more of palladium-calcium carbonate, palladium-barium sulfate, palladium-alumina, and palladium-zirconia; preferably, the palladium loading in the catalyst is preferably 0.5~5.0 wt%; preferably, the amount of the catalyst is 0.2%-2.0% of the mass of the raw material 3-methyl-1-pentyn-3-ol.

3. The method according to claim 1, characterized in that, The S1 hydrogenation reaction can be optionally carried out in a solvent, which includes one or more of hexane, heptane, octane, petroleum ether, cyclohexane, methylcyclohexane, toluene, xylene, ethyl acetate, and butyl acetate. Preferably, the amount of solvent used is 0.3-3.0 times the mass of the raw material 3-methyl-1-pentyn-3-ol.

4. The method according to claim 1, characterized in that, The S1 hydrogenation reaction includes organophosphorus compounds and zinc salt auxiliaries; preferably, the organophosphorus compounds include at least one of triphenylphosphine, tributylphosphine, tricyclohexylphosphine, tris(2-methylphenyl)phosphine, and tris(4-methylbenzene)phosphine, and are added in an amount of 100-300 ppm; the zinc salt includes one or more of zinc chloride, zinc bromide, zinc acetate, zinc nitrate, and zinc oxalate, and are added in an amount of 20-50 ppm.

5. The method according to any one of claims 1-4, characterized in that, The conversion rate of the raw material 3-methyl-1-pentyn-3-ol controlled by S1 is 90-98%.

6. The method according to claim 5, characterized in that, The hydrogenation reaction temperature in S1 is controlled at 30~60℃, preferably 40~60℃; and / or the hydrogen pressure is 0.2~2.0MPaG, preferably 1.0~2.0MPaG.

7. The method according to claim 1, characterized in that, The water washing temperature in S2 is 30~60℃; the water washing method includes one or more of the following: a phase separation tank with stirring, a sieve plate tower, a rotating disc extraction tower, and a turbine extraction tower.

8. The method according to claim 7, characterized in that, The water washing in S2 uses deionized water or a salt solution; preferably, the salt includes one or more of ammonium acetate, ammonium chloride, ammonium sulfate, ammonium carbonate, ammonium phosphate, and ammonium nitrate, and the concentration of the salt solution is preferably 2-5 wt%.

9. The method according to claim 8, characterized in that, The water washing process involves multiple washes, with the total mass of deionized water or salt solution used for washing being 30%-60% of the mass of the partial hydrogenation reaction solution; preferably, the washing process is carried out until the content of 3-methyl-1-pentyn-3-ol in the partial hydrogenation reaction solution is ≤0.1wt%.

10. The method according to claim 1 or 3, characterized in that, The distillation separation in S3 includes a product distillation step, with the following product distillation conditions: 10-15 trays, top temperature of 70-75℃, bottom temperature of 90-100℃, reflux ratio of 1-2:1, and top pressure of 15-20 kPa. The partially hydrogenated reaction liquid after water washing is optionally subjected to solvent removal and distillation treatment before being continuously fed from the bottom of the column, and 3-methyl-1-penten-3-ol is collected from the top of the column.