A process for the production of 1,2-pentanediol

Abstract

The present application relates to the technical field of production of pentanediol, in particular to a production method of 1,2-pentanediol, comprising that a reaction solution containing furfuryl alcohol is subjected to hydrogenation reaction under the action of a hydrogenation catalyst to generate 1,2-pentanediol, wherein the base value of the reaction solution is 100-500 ppm, and the hydrogenation catalyst comprises CuO 50wt%-70wt%, ZnO 10wt%-30wt%, Al2O3 5wt%-20wt% and La2O3 2wt%-10wt% based on the total mass of the hydrogenation catalyst; the selectivity of 1,2-pentanediol can be obviously improved by using the hydrogenation catalyst with the above specific composition and proportion, and the occurrence of side reactions is reduced; in combination with the control of the base value of the reaction solution within the above range, the occurrence of side reactions is also significantly reduced, especially the content of pentyl lactate in the crude product is reduced, thereby the separation difficulty of the product is simplified, the product purity is obviously improved, and the product quality is ensured. The obtained product has no odor and can be applied in the field of cosmetics, and belongs to cosmetic grade 1,2-pentanediol.

Description

Technical Field

[0001] This invention relates to the field of pentanediol production technology, and specifically to a method for producing 1,2-pentanediol. Background Technology

[0002] 1,2-Pentanediol (i.e., 1,2-PeD) is an important high-value-added chemical, mainly used in the production of polyester fibers, various cosmetic and skin care products, surfactants, disinfectants, printing inks, emulsifiers, plasticizers, pharmaceuticals, etc. It is also an important intermediate in the synthesis of the bactericide propiconazole.

[0003] Currently, the main synthetic routes for 1,2-pentanediol include the 1-pentene epoxidation and hydrolysis method and the n-butyraldehyde cyanation esterification and hydrogenation method. The 1-pentene epoxidation and hydrolysis method involves hydrogen peroxide epoxidation, which is a hazardous process and generates a large amount of wastewater. The n-butyraldehyde cyanation esterification and hydrogenation method involves the use of the highly toxic chemical hydrogen cyanide, is also a hazardous process, and produces a large amount of saline wastewater as a byproduct. Furthermore, the product's off-odor verification makes it unsuitable for downstream cosmetic applications.

[0004] The one-step catalytic hydrogenation of furfuryl alcohol to prepare 1,2-pentanediol is highly efficient, with a simple purification process and low investment, making it suitable for large-scale industrial production. The key to the furfuryl alcohol hydrogenation method lies in the development of suitable and efficient catalysts and production processes.

[0005] Patents CN201911107004.9 and CN201320723632.6 both report a method for producing 1,2-pentanediol from furfuryl alcohol using a noble metal catalyst. However, the highest yield of 1,2-pentanediol in this process is only about 40%, and the catalyst cost is high, making it difficult to industrialize. Patent CN116920854 discloses a method for preparing a catalyst and a method for selectively hydrogenating furfuryl alcohol to 1,2-pentanediol under the catalysis of the above catalyst. However, its 1,2-pentanediol selectivity is low, and there are many byproducts, especially an excessive amount of the key impurity valerate, which is difficult to separate from the main product, making it difficult to apply in the downstream cosmetics field.

[0006] Developing efficient non-precious metal catalysts to improve the selectivity of 1,2-pentanediol while controlling the content of key impurities to ensure product quality is crucial for the industrialization of furfuryl alcohol hydrogenation to 1,2-pentanediol. Summary of the Invention

[0007] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the prior art in the preparation of 1,2-pentanediol by hydrogenation of furfuryl alcohol, which has low selectivity leading to many by-products and difficulty in product separation leading to the content of key impurities in the pure product, thereby providing a method for producing 1,2-pentanediol.

[0008] This application provides a method for producing 1,2-pentanediol, comprising: a reaction solution containing furfuryl alcohol undergoing a hydrogenation reaction in the presence of a hydrogenation catalyst to produce 1,2-pentanediol; wherein the alkalinity of the reaction solution is 100-500 ppm; and the hydrogenation catalyst comprises, by weight, CuO 50wt%-70wt%, ZnO 10wt%-30wt%, Al2O3 5wt%-20wt%, and La2O3 2wt%-10wt%.

[0009] Furthermore, based on the total mass of the hydrogenation catalyst, the hydrogenation catalyst comprises 58wt%-62wt% CuO, 18wt%-22wt% ZnO, 12wt%-16wt% Al2O3 and 4wt%-6wt% La2O3.

[0010] Furthermore, based on the total mass of the hydrogenation catalyst, the hydrogenation catalyst comprises 60 wt% CuO, 20 wt% ZnO, 15 wt% Al2O3, and 5 wt% La2O3.

[0011] Furthermore, the alkalinity of the reaction solution is 200-300 ppm.

[0012] Furthermore, the alkalinity of the reaction solution can be controlled by adding an inorganic or organic base to the reaction solution;

[0013] Optionally, the inorganic base is selected from one or more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate.

[0014] Optionally, the organic base is selected from one or more of tetramethylammonium hydroxide, triethylamine, sodium methoxide, potassium ethoxide, and potassium tert-butoxide.

[0015] In some embodiments, an aqueous solution of an inorganic or organic base (e.g., sodium carbonate solution or tetramethylammonium hydroxide solution) may be added, with a mass percentage of 0.5-10 wt%, for example, 0.5 wt%, 1 wt%, 5 wt%, or 10 wt%.

[0016] Furthermore, the solvent of the reaction solution is selected from one or more of alcohol solvents (e.g., C1-C20 alcohol solvents), amide solvents (C1-C20 amide solvents), and alkane solvents (C1-C15 alkane solvents); preferably an alcohol solvent; more preferably methanol or ethanol.

[0017] Furthermore, the reaction pressure of the hydrogenation reaction is 2-10 MPa, preferably 4-8 MPa.

[0018] Furthermore, the reaction temperature of the hydrogenation reaction is 120-250℃, preferably 130-180℃.

[0019] Furthermore, the preparation method of the hydrogenation catalyst includes the following steps:

[0020] The hydrogenation catalyst is prepared by mixing a metal salt solution containing copper, zinc, aluminum and lanthanum salts with a precipitant solution, reacting, allowing it to stand and age, separating the solid and liquid, drying the precipitate, and calcining it.

[0021] Optionally, the reaction temperature is 40-80℃;

[0022] Optionally, the pH of the reaction system is 6.5-8;

[0023] Optionally, the static aging time is 0.5-3 hours;

[0024] Optionally, the drying temperature is 100-200℃ and the time is 5-10 hours;

[0025] Optionally, the moisture content of the dried precipitate is 1-5 wt%.

[0026] Optionally, the calcination temperature is 300-600℃ and the time is 2-5 hours;

[0027] Optionally, the copper salt is selected from one or more of copper nitrate and copper chloride; and / or, the zinc salt is selected from one or more of zinc nitrate and zinc chloride; and / or, the aluminum salt is selected from one or more of aluminum nitrate and aluminum chloride; and / or, the lanthanum salt is selected from one or more of lanthanum nitrate and lanthanum chloride; and / or, the precipitant is selected from one or more of sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, ammonium carbonate, or ammonia water.

[0028] Furthermore, the mass hourly space velocity (HSV) of furfuryl alcohol during the hydrogenation reaction is 0.1 h⁻¹. -1 -0.5h -1 .

[0029] Furthermore, the molar ratio of hydrogen to furfuryl alcohol during the hydrogenation reaction is 30-100:1, preferably 50:1.

[0030] Furthermore, the hydrogenation catalyst carries out the hydrogenation reaction in a mixed atmosphere of nitrogen and hydrogen.

[0031] The volume ratio of nitrogen to hydrogen in the mixed atmosphere is 75-85:20.

[0032] Furthermore, prior to the hydrogenation reaction, a step of reducing and activating the hydrogenation catalyst in a mixed atmosphere of nitrogen and hydrogen is included.

[0033] During the reduction activation process, the volume ratio of nitrogen to hydrogen is 90-95:5. The reduction activation temperature is 120-170℃.

[0034] Furthermore, the method for producing 1,2-pentanediol may include a purification step of the crude product after the hydrogenation reaction. This application does not limit the purification method; conventional methods in the art, such as distillation, can be used. For example, the number of trays could be 40-60, the top pressure 1-2.5 kPa, the top temperature 125-135°C, and the reflux ratio 8-12:1.

[0035] Furthermore, a trickle bed or a bubble bed is used for the hydrogenation reaction, with a trickle bed being preferred.

[0036] Furthermore, in the hydrogenation reaction, the furfuryl alcohol conversion rate is ≥99.2%, the 1,2-pentanediol selectivity is ≥78%, the valerolactone content in the crude 1,2-pentanediol is <500ppm, the purity of the pure 1,2-pentanediol is >99.9%, and the valerolactone content in the pure 1,2-pentanediol is <200ppm.

[0037] Optionally, in the hydrogenation reaction, the furfuryl alcohol conversion rate is 99.2%-99.7%, the 1,2-pentanediol selectivity is 78%-85%, the valerolactone content in the crude 1,2-pentanediol is <500ppm (e.g., 300ppm-480ppm), the purity of the pure 1,2-pentanediol is 99.9-99.96%, and the valerolactone content in the pure 1,2-pentanediol is <200ppm (e.g., 100-168ppm).

[0038] The technical solution of this invention has the following advantages:

[0039] 1. The present invention provides a method for producing 1,2-pentanediol, wherein a reaction solution containing furfuryl alcohol undergoes a hydrogenation reaction in the presence of a hydrogenation catalyst to produce 1,2-pentanediol. The alkalinity of the reaction solution is 100-500 ppm. Based on the total mass of the hydrogenation catalyst, the hydrogenation catalyst comprises 50 wt%-70 wt% CuO, 10 wt%-30 wt% ZnO, 5 wt%-20 wt% Al₂O₃, and 2 wt%-10 wt% La₂O₃. The specific composition and proportion of the hydrogenation catalyst significantly improves the selectivity of 1,2-pentanediol and reduces the occurrence of side reactions. Controlling the alkalinity of the reaction solution within the above-mentioned range also significantly reduces the occurrence of side reactions, especially reducing the content of valproic acid lactone in the crude product, thereby simplifying product separation, significantly improving product purity, and ensuring product quality. The resulting product is odorless and can be used in the cosmetics field, belonging to cosmetic-grade 1,2-pentanediol.

[0040] 2. The method for producing 1,2-pentanediol provided by the present invention, based on the total mass of the hydrogenation catalyst, comprises CuO 58wt%-62wt%, ZnO 18wt%-22wt%, Al2O3 12wt%-16wt%, and La2O3 4wt%-6wt%. By controlling the content of each substance in the hydrogenation catalyst within the above ranges, the conversion rate of furfuryl alcohol and the selectivity of 1,2-pentanediol can be further improved, and the occurrence of side reactions can be further reduced, thereby improving product purity.

[0041] 3. The method for producing 1,2-pentanediol provided by the present invention has an alkalinity of 200-300 ppm in the reaction solution. By controlling the alkalinity of the reaction solution within the above range, the conversion rate of furfuryl alcohol and the selectivity of 1,2-pentanediol can be further improved, and the occurrence of side reactions can be further reduced, thereby improving the purity of the product. Detailed Implementation

[0042] 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.

[0043] 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. V / V represents the volume ratio.

[0044] The reagents and solvents used in this invention can all be purchased from Aladdin Reagent Company.

[0045] The instrument used for catalyst performance evaluation was a Shimadzu GC-2010 gas chromatograph (FID) with a flame ionization detector (NOD) and nitrogen as the carrier gas. It was equipped with a DB-5 capillary column (5% phenylmethyl siloxane stationary phase, 30m × 0.32mm × 0.25μm) and a flame ionization detector (FID). The injector and detector temperatures were both 280℃. Column temperature was programmed: initial temperature 100℃, held for 0.5 minutes, then increased to 260℃ at a rate of 15℃ / min, and held for 5 minutes. Column pressure was 8.5868 psi (approximately 59.2 kPa), and the flow rate was 1.5 mL / min. Injection volume was 0.2 μL. Conversion and selectivity were calculated using the area normalization method. The purity of 1,2-pentanediol and the content of pentanolide in crude or pure 1,2-pentanediol were also calculated using the area normalization method.

[0046] Example 1

[0047] This embodiment provides a method for producing 1,2-pentanediol, comprising the following steps:

[0048] 100g of hydrogenation catalyst was loaded into a trickle bed reactor. The catalyst was reduced and activated in a nitrogen:hydrogen atmosphere of 95:5 (V / V) at 150℃, with the temperature rise controlled to not exceed 20℃. After the catalyst bed temperature rose no further, the nitrogen:hydrogen volume ratio was adjusted to 80:20 (V / V), and the reactor was kept at 150℃ for 24h. The reaction solution (i.e., an ethanol solution containing 20% ​​furfuryl alcohol by mass) was continuously introduced into the reactor, and the reaction pressure was controlled at 6MPa, the temperature at 150℃, and the mass hourly space velocity of furfuryl alcohol at 0.2h. -1 The molar ratio of hydrogen to furfuryl alcohol was 50:1, and 1 wt% sodium hydroxide solution was added to control the alkalinity of the reaction solution at 200 ppm. After stabilization for 8 hours, samples were taken for analysis. The furfuryl alcohol conversion rate, 1,2-pentanediol selectivity, and content of the key byproduct valproic acid are shown in Table 1.

[0049] The crude 1,2-pentanediol obtained from the reaction was distilled, with the number of trays controlled at 50, the top pressure at 2 kPaA, the top temperature at 130 °C, and the reflux ratio at 10:1, to obtain pure 1,2-pentanediol. The purity of the pure 1,2-pentanediol and the content of the key byproduct pentanelactone are shown in Table 1.

[0050] The specific preparation method of the hydrogenation catalyst used in this embodiment is as follows: 141.47g of copper nitrate, 46.54g of zinc nitrate, 62.67g of aluminum nitrate, and 9.97g of lanthanum nitrate were dissolved in water and diluted to a final volume of 1000mL to obtain a mixed solution. A 10wt% sodium carbonate solution was added dropwise to the mixed solution to carry out a precipitation reaction, and the pH value of the precipitation reaction was controlled at 7.5 and the temperature at 60℃. After the reaction was completed, the solution was allowed to stand for 2 hours for aging, then filtered, washed, dried at 150℃ for 8 hours (moisture content of 3%), and calcined at 400℃ for 3 hours to obtain the hydrogenation catalyst. Based on the total mass of the hydrogenation catalyst, the composition of the hydrogenation catalyst is: CuO content of 60wt%, ZnO content of 20wt%, Al2O3 content of 15wt%, and La2O3 content of 5wt%.

[0051] Example 2

[0052] This embodiment provides a method for producing 1,2-pentanediol, which is basically the same as that in Example 1, except that in the preparation of the hydrogenation catalyst, "165.04g of copper nitrate, 34.91g of zinc nitrate, 41.78g of aluminum nitrate, and 9.97g of lanthanum nitrate are dissolved in water" instead of "141.47g of copper nitrate, 46.54g of zinc nitrate, 62.67g of aluminum nitrate, and 9.97g of lanthanum nitrate are dissolved in water" in Example 1. The remaining process conditions are the same as in Example 1. The composition of the hydrogenation catalyst obtained is: CuO content of 70wt%, ZnO content of 15wt%, Al2O3 content of 10wt%, and La2O3 content of 5wt%.

[0053] Example 3

[0054] This embodiment provides a method for producing 1,2-pentanediol, which is basically the same as that in Example 1, except that in the preparation of the hydrogenation catalyst, "129.68g of copper nitrate, 58.18g of zinc nitrate, 71.03g of aluminum nitrate, and 5.98g of lanthanum nitrate are dissolved in water" instead of "141.47g of copper nitrate, 46.54g of zinc nitrate, 62.67g of aluminum nitrate, and 9.97g of lanthanum nitrate are dissolved in water" in Example 1. The remaining process conditions are the same as in Example 1. The composition of the obtained hydrogenation catalyst is: CuO content of 55wt%, ZnO content of 25wt%, Al2O3 content of 17wt%, and La2O3 content of 3wt%.

[0055] Example 4

[0056] This embodiment provides a method for producing 1,2-pentanediol, comprising the following steps:

[0057] 100g of hydrogenation catalyst (prepared using the same method as the hydrogenation catalyst in Example 1) was loaded into a trickle bed reactor. The catalyst was reduced and activated in a nitrogen:hydrogen atmosphere of 95:5 (V / V) at 150°C, with the temperature rise controlled to not exceed 20°C. After the catalyst bed temperature rose no further, the nitrogen:hydrogen volume ratio was adjusted to 80:20 (V / V), and the reactor was kept at 150°C for 24 hours. The reaction solution (i.e., an ethanol solution containing 20% ​​furfuryl alcohol) was continuously introduced into the reactor, and the reaction pressure was controlled at 5MPa, the temperature at 160°C, and the mass hourly space velocity (HSV) of furfuryl alcohol at 0.1 h⁻¹. -1 The molar ratio of hydrogen to furfuryl alcohol was 50:1, and 10 wt% tetramethylammonium hydroxide solution was added to control the alkalinity of the reaction solution at 250 ppm. After stabilization for 8 hours, samples were taken for analysis. The furfuryl alcohol conversion rate, 1,2-pentanediol selectivity, and content of the key byproduct valproic acid are shown in Table 1.

[0058] The crude 1,2-pentanediol obtained from the reaction was distilled, with the number of trays controlled at 50, the top pressure at 2 kPaA, the top temperature at 130 °C, and the reflux ratio at 10:1, to obtain pure 1,2-pentanediol. The purity of the pure 1,2-pentanediol and the content of the key byproduct pentanelactone are shown in Table 1.

[0059] Example 5

[0060] This embodiment provides a method for producing 1,2-pentanediol, which is basically the same as that in Example 1, except that the alkalinity of the reaction solution is controlled differently during the hydrogenation reaction. In this embodiment, a 1wt% sodium hydroxide solution is used to control the alkalinity of the reaction solution to 500ppm.

[0061] Example 6

[0062] This embodiment provides a method for producing 1,2-pentanediol, which is basically the same as that in Example 1, except that the alkalinity of the reaction solution is controlled differently during the hydrogenation reaction. In this embodiment, a 1 wt% sodium hydroxide solution is used to control the alkalinity of the reaction solution to 100 ppm.

[0063] Example 7

[0064] This embodiment provides a method for producing 1,2-pentanediol, which is basically the same as that in Example 1, except that the reaction solvent is different. In this embodiment, "N,N-dimethylformamide solution containing 20% ​​furfuryl alcohol by mass" is used instead of "ethanol solution containing 20% ​​furfuryl alcohol by mass" in Example 1.

[0065] Example 8

[0066] This embodiment provides a method for producing 1,2-pentanediol, which is basically the same as that in Example 1, except that the aging time is different during the preparation of the hydrogenation catalyst. The aging time in this embodiment is 0.5 h.

[0067] Comparative Example 1

[0068] This comparative example provides a method for producing 1,2-pentanediol, which is basically the same as that in Example 1, except that in the preparation of the hydrogenation catalyst, "153.25g of copper nitrate, 46.54g of zinc nitrate, 65.67g of aluminum nitrate, and 0g of lanthanum nitrate are dissolved in water" instead of "141.47g of copper nitrate, 46.54g of zinc nitrate, 62.67g of aluminum nitrate, and 9.97g of lanthanum nitrate are dissolved in water" in Example 1. The remaining process conditions are the same as in Example 1. The composition of the hydrogenation catalyst obtained is: CuO content of 65wt%, ZnO content of 20wt%, Al2O3 content of 15wt%, and La2O3 content of 0wt%.

[0069] Comparative Example 2

[0070] This embodiment provides a method for producing 1,2-pentanediol, which is basically the same as that in Example 1, except that sodium hydroxide solution is not added to the reaction solution during the hydrogenation reaction process, and the alkalinity of the reaction solution is monitored to be less than 5 ppm.

[0071] The experimental results of each embodiment and comparative example are shown in Table 1.

[0072] Table 1 Experimental Results

[0073]

[0074] The test results of the above examples and comparative examples show that, compared with comparative examples 1-2, the cosmetic-grade 1,2-pentanediol prepared by the methods of each example in this invention significantly improves the furfuryl alcohol conversion rate (≥99.2%) and the 1,2-pentanediol selectivity (≥78%), and greatly reduces the content of by-products, with the content of the key impurity valerate being <500ppm. Separation is easier, and the purity of the purified product after distillation is significantly improved (purity >99.9%, valerate content <200ppm). It also has the significant advantages of simple operation and ease of industrialization, is odorless, and can be applied in the cosmetics field.

[0075] 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 producing 1,2-pentanediol, characterized in that, The reaction solution containing furfuryl alcohol undergoes a hydrogenation reaction in the presence of a hydrogenation catalyst to produce 1,2-pentanediol. The alkalinity of the reaction solution is 100-500 ppm. The hydrogenation catalyst, based on its total mass, comprises: CuO 50wt%-70wt%, ZnO 10wt%-30wt%, Al2O3 5wt%-20wt%, and La2O3 2wt%-10wt%.

2. The production method according to claim 1, characterized in that, The hydrogenation catalyst has the following composition based on its total mass: CuO 58wt%-62wt%, ZnO 18wt%-22wt%, Al2O3 12wt%-16wt%, and La2O3 4wt%-6wt%.

3. The production method according to claim 1 or 2, characterized in that, The alkalinity of the reaction solution is 200-300 ppm.

4. The production method according to claim 1 or 2, characterized in that, The alkalinity of the reaction solution is controlled by adding an inorganic or organic base.

5. The production method according to claim 4, characterized in that, The inorganic base is selected from one or more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate.

6. The production method according to claim 4, characterized in that, The organic base is selected from one or more of tetramethylammonium hydroxide, triethylamine, sodium methoxide, potassium ethoxide, and potassium tert-butoxide.

7. The production method according to claim 1 or 2, characterized in that, The solvent of the reaction solution is selected from one or more of alcohol solvents, amide solvents, and alkane solvents.

8. The production method according to claim 7, characterized in that, The solvent for the reaction solution is an alcohol-based solvent.

9. The production method according to claim 7, characterized in that, The solvent for the reaction solution is methanol or ethanol.

10. The production method according to claim 1 or 2, characterized in that, The reaction pressure for the hydrogenation reaction is 2-10 MPa.

11. The production method according to claim 10, characterized in that, The reaction pressure for the hydrogenation reaction is 4-8 MPa.

12. The production method according to claim 1 or 2, characterized in that, The reaction temperature for the hydrogenation reaction is 120-250℃.

13. The production method according to claim 12, characterized in that, The reaction temperature for the hydrogenation reaction is 130-180℃.

14. The production method according to claim 1 or 2, characterized in that, The preparation method of the hydrogenation catalyst includes the following steps: The hydrogenation catalyst is prepared by mixing a metal salt solution containing copper, zinc, aluminum and lanthanum salts with a precipitant solution, reacting, allowing it to stand for aging, separating the solid and liquid phases, drying the precipitate, and calcining it.

15. The production method according to claim 14, characterized in that, The reaction temperature is 40-80℃.

16. The production method according to claim 14, characterized in that, The pH value of the reaction system is 6.5-8.

17. The production method according to claim 14, characterized in that, The static aging time is 0.5-3 hours.

18. The production method according to claim 14, characterized in that, The drying temperature is 100-200℃, and the time is 5-10 hours.

19. The production method according to claim 14, characterized in that, The water content of the dried precipitate is 1-5 wt%.

20. The production method according to claim 14, characterized in that, The roasting temperature is 300-600℃ and the time is 2-5 hours.

21. The production method according to claim 14, characterized in that, The copper salt is selected from one or more of copper nitrate and copper chloride; and / or, the zinc salt is selected from one or more of zinc nitrate and zinc chloride; and / or, the aluminum salt is selected from one or more of aluminum nitrate and aluminum chloride; and / or, the lanthanum salt is selected from one or more of lanthanum nitrate and lanthanum chloride; and / or, the precipitant is selected from one or more of sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, ammonium carbonate, or ammonia water.

22. The production method according to claim 1 or 2, characterized in that, The hydrogenation reaction is carried out using a trickle bed or a bubble bed; and / or, the hydrogenation reaction is followed by a purification step of the crude product; and / or, the mass hourly space velocity (WHSV) of furfuryl alcohol during the hydrogenation reaction is 0.1 h⁻¹. -1 -0.5 h -1 ; and / or, the molar ratio of hydrogen to furfuryl alcohol during the hydrogenation reaction is 30-100:

1.

23. The production method according to claim 1 or 2, characterized in that, In the hydrogenation reaction, the conversion rate of furfuryl alcohol is ≥99.2%, the selectivity of 1,2-pentanediol is ≥78%, the content of valproic acid in crude 1,2-pentanediol is <500ppm, the purity of pure 1,2-pentanediol is >99.9%, and the content of valproic acid in pure 1,2-pentanediol is <200ppm.

24. The production method according to claim 23, characterized in that, In the hydrogenation reaction, the conversion rate of furfuryl alcohol is 99.2%-99.7%, the selectivity of 1,2-pentanediol is 78%-85%, the content of valproic acid in crude 1,2-pentanediol is <500ppm, the purity of pure 1,2-pentanediol is 99.9-99.96%, and the content of valproic acid in pure 1,2-pentanediol is <200ppm.

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