A method for preparing 1,3-cyclopentanediol from cyclopentadiene

Abstract

This invention provides a method for preparing 1,3-cyclopentanediol from cyclopentadiene and an apparatus system for implementing the method. The method includes: performing a hydroxylation reaction on a mixture of cyclopentadiene and a peroxide and an organic acid to obtain a hydroxylated mixed intermediate product; distilling the hydroxylated mixed intermediate product to obtain a hydroxylated mixed product and an aqueous solution of the organic acid; reacting the hydroxylated mixed product with hydrogen in the presence of a hydrogenation catalyst to obtain a hydrogenated mixed alcohol product; and distilling the hydrogenated mixed alcohol product to obtain high-purity 1,3-cyclopentanediol. The method of this invention features mild reaction conditions, high efficiency and environmental friendliness, and can obtain 1,3-cyclopentanediol in high yield.

Description

Technical Field

[0001] This invention relates to a method for preparing 1,3-cyclopentadiol from cyclopentadiene and an apparatus system for carrying out the method. Background Technology

[0002] 1,3-Cyclopentanediol is an important chemical raw material, widely used in the synthesis of polyesters, polyurethanes, pesticides, and other organic synthesis intermediates. Cyclopentadiene, as a major product of the C5 fraction of ethylene cracking, is readily available and inexpensive, making it a suitable raw material for 1,3-cyclopentanediol synthesis. However, due to the presence of conjugated double bonds in cyclopentadiene, it is extremely unstable and can self-polymerize into dicyclopentadiene at room temperature. Therefore, there are few reports on the synthesis of 1,3-cyclopentanediol using cyclopentadiene as a raw material. A method for preparing 1,3-cyclopentanediol using cyclopentadiene as a raw material was reported in the literature (J. Am. Chem. Soc., 1963, 85(14): 2066). 1,3-cyclopentanediol was prepared by reducing cyclopentadiene with borane at a low temperature (0℃) and then oxidizing it with hydrogen peroxide. However, the preparation process described in this method requires the use of highly toxic borane as a reducing agent, which does not conform to the concept of green and environmentally friendly synthesis. Furthermore, in order to prevent cyclopentadiene from self-polymerizing, the reaction temperature needs to be precisely controlled at 0°C, which requires a low-temperature refrigeration process, making the entire synthesis process very complex and unsuitable for large-scale industrial development.

[0003] Patent CN106866364B discloses a method for preparing 1,3-cyclopentanediol from furfural. This method involves a rearrangement reaction of furfural's selective hydrogenation product, furfuryl alcohol, to obtain hydroxycyclopentenone, which is then hydrogenated to produce 1,3-cyclopentanediol. However, the furfural used in this method originates from the hydrolysis of biomass under concentrated sulfuric acid, generating a large amount of acidic wastewater. Considering the entire industry chain, the biomass-based furfural-to-1,3-cyclopentanediol process suffers from serious environmental pollution drawbacks.

[0004] In summary, addressing the shortcomings of existing technologies for preparing 1,3-cyclopentadiol, such as severe environmental pollution and harsh synthesis conditions, this invention utilizes readily available and inexpensive cyclopentadiene from the petrochemical industry as a raw material. Leveraging the aromaticity of the conjugated double bonds in the cyclopentadiene molecule, a novel method for preparing 1,3-cyclopentadiol using the rapid addition of peroxides to cyclopentadiene has been developed. This method features mild reaction conditions and is highly efficient and environmentally friendly. Summary of the Invention

[0005] To address the above problems, in one aspect, the present invention provides a method for preparing 1,3-cyclopentanediol from cyclopentadiene, the method comprising:

[0006] (1) Cyclopentadiene was mixed with peroxide and organic acid to carry out a hydroxylation reaction to obtain a hydroxylated mixed intermediate product;

[0007] (2) The hydroxylated mixed intermediate product of step (1) is distilled to obtain the hydroxylated mixed product and an aqueous solution of organic acid. Optionally, the water and organic acid in the aqueous solution of organic acid are separated and the separated organic acid is returned to step (1) for recycling.

[0008] (3) The hydroxylated mixed product from step (2) is reacted with hydrogen under the action of a hydrogenation catalyst to obtain a hydrogenated mixed alcohol product;

[0009] (4) The hydrogenated mixed alcohol product is distilled to obtain 1,3-cyclopentanediol.

[0010] In another aspect, the present invention provides an apparatus system for implementing the above-described method of the present invention, wherein the apparatus system comprises the following units:

[0011] Raw material mixing tank;

[0012] An oxidation reactor, wherein the outlet of the raw material mixing tank is connected in fluid communication to the inlet of the oxidation reactor;

[0013] An oxidation product separation distillation column, wherein the outlet of the oxidation reactor is connected to the inlet of the oxidation product separation distillation column in a fluid communication manner;

[0014] An acid-water separation tower is provided, wherein the top outlet of the oxidation product separation distillation tower is fluidly connected to the inlet of the acid-water separation tower, the top outlet of the acid-water separation tower is fluidly connected to the inlet of the raw material mixing tank, and the bottom outlet of the acid-water separation tower is used to discharge water.

[0015] A hydrogenation unit, wherein the bottom outlet of the oxidation product separation distillation column is fluidly connected to the inlet of the hydrogenation unit; and

[0016] A hydrogenation product separation tower is provided, wherein the outlet of the hydrogenation unit is connected to the inlet of the hydrogenation product separation tower in a fluid communication manner, the top outlet of the hydrogenation product separation tower is used to discharge methanol, and the bottom outlet of the hydrogenation product separation tower is used to discharge 1,3-cyclopentanediol.

[0017] The method and equipment system for preparing 1,3-cyclopentadiol from cyclopentadiene as a raw material described in this invention have the following beneficial effects:

[0018] 1. The cyclopentadiene used in this invention is derived from the cyclopentadiene in the C5 fraction of ethylene cracking. The raw material is readily available and inexpensive.

[0019] 2. The hydroxylation and hydrogenation reactions involved in the preparation process of this invention can successfully produce 1,3-cyclopentanediol in high yield using inexpensive and readily available oxidants, organic acids and hydrogenation catalysts. This is a novel synthetic method that is not disclosed or recognized in the prior art. Moreover, compared with the existing synthetic methods, the method of this invention has the advantages of mild reaction conditions, simple process and green environmental protection.

[0020] 3. The method described in this invention utilizes the rapid addition of peroxide to cyclopentadiene to prepare 1,3-cyclopentadiol. The addition reaction rate of peroxide to cyclopentadiene is fast, creating a competitive advantage over the dimerization reaction of cyclopentadiene, resulting in high selectivity for cyclopentadiol and inhibiting the formation of the dimer product dicyclopentadiene. This allows the yield of 1,3-cyclopentadiol to reach 65%, a high yield that is extremely beneficial for large-scale industrial production, thus solving the problem of the difficulty in large-scale, efficient industrial production of 1,3-cyclopentadiol. Attached Figure Description

[0021] The accompanying drawings are part of the specification and, together with the detailed description, provide a further explanation of the invention, but are not intended to limit the invention.

[0022] Figure 1 This is a process diagram illustrating the preparation of 1,3-cyclopentanediol according to an exemplary embodiment of the present invention.

[0023] 1. Cyclopentadiene; 2. Hydrogen peroxide; 3. Formic acid; 4. Water; 5. Methanol; 6. Target product 1,3-cyclopentadiol.

[0024] Ⅰ. Raw material mixing tank; Ⅱ. Oxidation reaction vessel; Ⅲ. Oxidation product separation distillation column; Ⅳ. Formic acid-water separation column; Ⅴ. Hydrogenation unit; Ⅵ. Hydrogenation product separation column. Detailed Implementation

[0025] The specific embodiments of the present invention will be described in detail below. The specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0026] This invention provides a method for preparing 1,3-cyclopentadiol from cyclopentadiene, the method comprising:

[0027] (1) Cyclopentadiene was mixed with peroxide and organic acid to carry out a hydroxylation reaction to obtain a hydroxylated mixed intermediate product;

[0028] (2) The hydroxylated mixed intermediate product of step (1) is distilled to obtain the hydroxylated mixed product and an aqueous solution of organic acid. Optionally, the water and organic acid in the aqueous solution of organic acid are separated and the separated organic acid is returned to step (1) for recycling.

[0029] (3) The hydroxylated mixed product from step (2) is reacted with hydrogen under the action of a hydrogenation catalyst to obtain a hydrogenated mixed alcohol product;

[0030] (4) The hydrogenated mixed alcohol product is distilled to obtain high-purity 1,3-cyclopentanediol.

[0031] In some embodiments, the cyclopentadiene:peroxide:organic acid ratio in step (1) is 1:(0.1-10):(0.1-10), for example 1:(0.5-1):(0.5-2), by molar percentage.

[0032] In some embodiments, the cyclopentadiene in step (1) can be pure cyclopentadiene or an aqueous solution of cyclopentadiene with a mass concentration of 0.01% to 100%, such as an aqueous solution of cyclopentadiene with a mass concentration of 95%.

[0033] In some embodiments, the peroxide in step (1) is one or more of hydrogen peroxide, ozone, peroxyformic acid, peracetic acid, peroxym-chlorobenzoic acid, tert-butylhydrogen peroxide, and cumene peroxide.

[0034] In some embodiments, the organic acid in step (1) is one or more of formic acid, acetic acid, propionic acid, butyric acid, and chloroacetic acid.

[0035] In some embodiments, the hydroxylation reaction in step (1) is carried out in a batch reactor, a tubular reactor, or a fixed-bed reactor.

[0036] In some further preferred embodiments, the hydroxylation reaction conditions in step (1) are: temperature 0-100℃, pressure 0-5.0 MPa, and reaction time 0.01-10.0 h; preferably, temperature 40-55℃ (e.g., 40-45℃ or 45-55℃), pressure 0.5-2.0 MPa (e.g., 0.5-1.0 MPa or 1.0-2.0 MPa), and reaction time 2.0-4.0 h (e.g., 2.0-3.0 h or 3.0-4.0 h).

[0037] In some preferred embodiments, when step (1) uses a batch reactor, the reaction time is 0.01-10.0 h (e.g., 2.0-4.0 h); in other preferred embodiments, when step (1) uses a fixed-bed or tubular reactor, the mass hourly space velocity is 0.001 h⁻¹. -1 -100h -1 .

[0038] In some embodiments, the distillation conditions in step (2) are: 2-30 plates in the distillation column, a top temperature of 90-110°C (e.g., 95-107°C), a bottom temperature of 180-230°C (e.g., 180-220°C), and an operating pressure of 0.3-1.5 bar (e.g., 0.3-1.0 bar).

[0039] In some embodiments, the separation conditions for water and organic acid in step (2) are: 5-30 trays in the distillation column, a top temperature of 60-100°C (e.g., 85-95°C), a bottom temperature of 120-150°C (e.g., 125-145°C), and an operating pressure of 0.2-1.0 bar (e.g., 0.2-0.9 bar).

[0040] In some embodiments, the hydrogenation reaction in step (3) is carried out in a batch reactor, a fixed-bed reactor or a tubular reactor; the ratio of hydrogen to hydroxylation mixture is (20-2000):1 (in molar percentage).

[0041] In some preferred embodiments, the hydrogenation reaction conditions in step (3) are: temperature 0-300℃, hydrogen pressure 0.1-10 MPa, and reaction time 0.01-10.0 h; preferably, temperature 90-180℃ (e.g., 90-160℃ or 160-180℃) and pressure 1.5-3.0 MPa (e.g., 1.5-2.0 MPa or 2.0-3.0 MPa).

[0042] In some preferred embodiments, when step (3) uses a batch reactor, the reaction time is 0.01-10.0 h; when step (3) uses a fixed-bed or tubular reactor, the mass hourly space velocity is 0.001 h⁻¹. -1 -100h -1 (e.g., 0.7h) -1 -3.0h -1 ).

[0043] In some embodiments, the hydrogenation catalyst in step (3) is one or more of the following catalysts: (a) a supported metal catalyst in which one or more of the following metals Pt, Pd, Ru, Ir, Ni, Co, Cu, and Zn are supported on a carrier: (b) a transition metal carbide or nitride catalyst; (c) a Raney nickel catalyst; and (d) an amorphous alloy catalyst.

[0044] In some preferred embodiments, the hydrogenation catalyst in step (3) is one or a mixture of two or more of the following catalysts: Ni / SiO2 type catalyst, Ni / Al2O3 type catalyst and Pd / Al2O3 type catalyst.

[0045] In some embodiments, the amount of hydrogenation catalyst added in step (3) is 0.01-20% of the mass of the hydrogenation reaction solution.

[0046] In some embodiments, the distillation column in step (4) is a plate distillation column or a packed distillation column; the theoretical number of distillation columns is 5-80 (e.g., 5-10), the distillation column pressure is 10.3-110.0 kPa or 10.3-103.1 kPa (e.g., 80-110.0 kPa); the column bottom temperature is 180-230℃ (e.g., 195-210℃); and the column top temperature is 50-70℃ (e.g., 55-70℃).

[0047] In some embodiments, the present invention also provides an apparatus system for implementing the above-described method of the present invention, wherein the apparatus system comprises the following units:

[0048] Raw material mixing tank;

[0049] An oxidation reactor, wherein the outlet of the raw material mixing tank is connected in fluid communication to the inlet of the oxidation reactor;

[0050] An oxidation product separation distillation column, wherein the outlet of the oxidation reactor is connected to the inlet of the oxidation product separation distillation column in a fluid communication manner;

[0051] An acid-water separation tower is provided, wherein the top outlet of the oxidation product separation distillation tower is fluidly connected to the inlet of the acid-water separation tower, the top outlet of the acid-water separation tower is fluidly connected to the inlet of the raw material mixing tank, and the bottom outlet of the acid-water separation tower is used to discharge water.

[0052] A hydrogenation unit, wherein the bottom outlet of the oxidation product separation distillation column is fluidly connected to the inlet of the hydrogenation unit; and

[0053] A hydrogenation product separation tower is provided, wherein the outlet of the hydrogenation unit is connected to the inlet of the hydrogenation product separation tower in a fluid communication manner, the top outlet of the hydrogenation product separation tower is used to discharge methanol, and the bottom outlet of the hydrogenation product separation tower is used to discharge 1,3-cyclopentanediol.

[0054] The method provided by the present invention will be further described below with reference to the accompanying drawings. However, those skilled in the art will understand that the scope of the present invention is not limited to the description in the accompanying drawings.

[0055] Cyclopentadiene, peroxide, and organic acid are mixed in a ratio of 1:(0.1-10):(0.1-10) (by molar percentage) and fed into a batch reactor, tubular reactor, or fixed-bed reactor for hydroxylation. The reaction is carried out at a temperature of 0-100℃ and a pressure of 0-5.0 MPa for 0.01-10 h to obtain a mixed hydroxylated intermediate. The mixed hydroxylated intermediate is then distilled in a distillation column with 2-30 trays, where the top temperature is 90-110℃, the bottom temperature is 180-230℃, and the operating pressure is 0.3-1.5 bar to obtain the mixed hydroxylated product and an aqueous solution of the organic acid. The organic acid aqueous solution is separated in a distillation column with 5-30 trays, a top temperature of 60-100℃, a bottom temperature of 120-150℃, and an operating pressure of 0.2-1.0 bar. The obtained organic acid is returned to the feed for reuse. The hydroxylated mixed product is fed into a batch reactor, fixed-bed reactor, or tubular reactor and subjected to a hydrogenation reaction with a hydrogenation catalyst at a temperature of 0-300℃ and a hydrogen pressure of 0.1-10 MPa to obtain a hydrogenated mixed alcohol product. The hydrogenated mixed alcohol product is then purified by distillation in a plate distillation column or packed distillation column with 5-80 theoretical trays, a distillation column pressure of 10.3-103.1 kPa, a bottom temperature of 180-230℃, and a top temperature of 50-70℃ to obtain high-purity 1,3-cyclopentanediol.

[0056] The present invention will be described below through specific embodiments, but the present invention is not limited thereto.

[0057] Example

[0058] The present invention will be further described in detail below through embodiments. These embodiments are merely illustrative and should not be construed as limiting the scope of the invention. All technical solutions and modifications based on the above description of the present invention fall within the scope of the present invention. Unless otherwise stated, all concentrations mentioned below are mass concentrations, and all solutions mentioned are aqueous solutions.

[0059] Example 1

[0060] In this embodiment, the concentration of cyclopentadiene is 95%, the peroxide is selected as a 30% hydrogen peroxide aqueous solution, and the organic acid is chloroacetic acid with a concentration of 95%.

[0061] Cyclopentadiene, peroxide, and organic acid were mixed in a 1:0.5:1 ratio (molar percentage) and fed into a batch reactor. The reaction was carried out at 40°C and 0.5 MPa for 2 hours to obtain a hydroxylated mixed intermediate product. The hydroxylated mixed intermediate product was then distilled at a top temperature of 105°C, a bottom temperature of 200°C, and an operating pressure of 1.0 bar in a distillation column with 8 trays, yielding an aqueous solution of organic acid and the hydroxylated mixed product. The aqueous solution of organic acid was then separated at a top temperature of 86°C, a bottom temperature of 128.5°C, a distillation column with 25 trays, and an operating pressure of 0.6 bar, with the organic acid being returned to the feed for reuse.

[0062] The hydroxylated mixture was fed into a fixed-bed reactor at a temperature of 160°C, a hydrogen pressure of 2.0 MPa, and a space velocity of 1.0 h⁻¹. -1 Under certain conditions, the mixture was contacted with a Ni / SiO2 hydrogenation catalyst to undergo a hydrogenation reaction, yielding a hydrogenated mixed alcohol product. The hydrogenated mixed alcohol product was then fed into a plate distillation column for rectification. The column had 10 theoretical plates, a pressure of 1.1 bar, a bottom temperature of 201℃, and a top temperature of 65.5℃, yielding high-purity 1,3-cyclopentanediol. The reaction results are shown in Table 1.

[0063] Example 2

[0064] In this embodiment, the concentration of cyclopentadiene is 90%, the peroxide is selected as a 30% hydrogen peroxide aqueous solution, and the organic acid is formic acid with a concentration of 95%.

[0065] Cyclopentadiene, peroxide, and organic acid were mixed in a 1:1:1 ratio (molar percentage) and fed into a batch reactor. The reaction was carried out at 45°C and 1.0 MPa for 3 hours to obtain a hydroxylated mixed intermediate product. The hydroxylated mixed intermediate product was then distilled at a top temperature of 95°C, a bottom temperature of 180°C, and an operating pressure of 0.3 bar in a distillation column with 8 trays, yielding an aqueous solution of organic acid and the hydroxylated mixed product. The aqueous solution of organic acid was then separated at a top temperature of 60°C, a bottom temperature of 120°C, and a distillation column with 25 trays in a pressure of 0.2 bar, with the organic acid being returned to the feed for reuse.

[0066] The hydroxylated mixture was fed into a fixed-bed reactor at a temperature of 180°C, a hydrogen pressure of 3.0 MPa, and a space velocity of 3.0 h⁻¹. -1Under certain conditions, the mixture was reacted with a Ni / Al2O3 hydrogenation catalyst to undergo a hydrogenation reaction, yielding a hydrogenated mixed alcohol product. This hydrogenated mixed alcohol product was then fed into a plate distillation column for rectification. The column had 8 theoretical plates, a pressure of 0.8 bar, a bottom temperature of 196°C, and a top temperature of 55°C, yielding high-purity 1,3-cyclopentanediol. The reaction results are shown in Table 1.

[0067] Example 3

[0068] In this embodiment, the concentration of cyclopentadiene is 95%, the peroxide is selected as a 70% aqueous solution of peroxychlorobenzoic acid, and the organic acid is acetic acid with a concentration of 99%.

[0069] Cyclopentadiene, peroxide, and organic acid were mixed in a 1:1:0.5 ratio (molar percentage) and fed into a batch reactor. The reaction was carried out at 40°C and 1.0 MPa for 4 hours to obtain a hydroxylated mixed intermediate product. The hydroxylated mixed intermediate product was then distilled at a top temperature of 107°C, a bottom temperature of 220°C, and an operating pressure of 1.0 bar in a 10-plate distillation column to obtain an aqueous solution of organic acid and the hydroxylated mixed product. The aqueous solution of organic acid was then separated at a top temperature of 100°C, a distillation column with 25 plates, a bottom temperature of 150°C, and an operating pressure of 1.0 bar. The organic acid was returned to the feed for reuse.

[0070] The hydroxylated mixture was fed into a fixed-bed reactor at a temperature of 90°C, a hydrogen pressure of 3.0 MPa, and a space velocity of 0.7 h⁻¹. -1 Under certain conditions, the mixture was contacted with a Pd / Al2O3 hydrogenation catalyst to undergo a hydrogenation reaction, yielding a hydrogenated mixed alcohol product. The hydrogenated mixed alcohol product was then fed into a plate distillation column for rectification. The column had 5 theoretical plates, a pressure of 0.9 bar, a bottom temperature of 200℃, and a top temperature of 64.5℃, yielding high-purity 1,3-cyclopentanediol. The reaction results are shown in Table 1.

[0071] Example 4

[0072] In this embodiment, the cyclopentadiene concentration is 95%, the peroxide is tert-butyl hydroperoxide, and the organic acid is formic acid with a concentration of 95%.

[0073] Cyclopentadiene, peroxide, and organic acid were mixed in a 1:1:1 ratio (molar percentage) and fed into a batch reactor. The reaction was carried out at 55°C and 2.0 MPa for 4 hours to obtain a hydroxylated mixed intermediate product. The hydroxylated mixed intermediate product was then distilled at a top temperature of 100°C, a bottom temperature of 210°C, and an operating pressure of 1.0 bar in a 10-plate distillation column to obtain an aqueous solution of organic acid and the hydroxylated mixed product. The aqueous solution of organic acid was then separated at a top temperature of 95°C, a bottom temperature of 145°C, a 30-plate distillation column, and an operating pressure of 0.6 bar to obtain the organic acid, which was returned to the feed for reuse.

[0074] The hydroxylated mixture was fed into a fixed-bed reactor at a temperature of 95°C, a hydrogen pressure of 1.5 MPa, and a space velocity of 0.9 h⁻¹. -1 Under certain conditions, the mixture was contacted with a Pd / Al2O3 hydrogenation catalyst to undergo a hydrogenation reaction, yielding a hydrogenated mixed alcohol product. The hydrogenated mixed alcohol product was then fed into a plate distillation column for rectification. The column had 10 theoretical plates, a pressure of 1.0 bar, a bottom temperature of 210℃, and a top temperature of 68.5℃, yielding high-purity 1,3-cyclopentanediol. The reaction results are shown in Table 1.

[0075] Example 5

[0076] In this embodiment, the concentration of cyclopentadiene is 95%, the peroxide is selected as a 30% hydrogen peroxide aqueous solution, and the organic acid is acetic acid with a concentration of 99%.

[0077] Cyclopentadiene, peroxide, and organic acid were mixed in a 1:1:2 ratio (molar percentage) and fed into a batch reactor. The reaction was carried out at 40°C and 2.0 MPa for 3 hours to obtain a hydroxylated mixed intermediate product. The hydroxylated mixed intermediate product was then distilled at a top temperature of 105°C, a bottom temperature of 200°C, and an operating pressure of 0.9 bar in a distillation column with 8 trays, yielding an aqueous solution of organic acid and the hydroxylated mixed product. The aqueous solution of organic acid was then separated at a top temperature of 95°C, a bottom temperature of 140°C, and a distillation column with 25 trays in a distillation column at an operating pressure of 0.9 bar, with the organic acid being returned to the feed for reuse.

[0078] The hydroxylated mixture was fed into a fixed-bed reactor at a temperature of 90°C, a hydrogen pressure of 2.0 MPa, and a space velocity of 1.0 h⁻¹. -1Under certain conditions, the mixture was contacted with a Pd / Al2O3 hydrogenation catalyst to undergo a hydrogenation reaction, yielding a hydrogenated mixed alcohol product. The hydrogenated mixed alcohol product was then fed into a plate distillation column for rectification. The column had 10 theoretical plates, a pressure of 1.0 bar, a bottom temperature of 200℃, and a top temperature of 65℃, yielding high-purity 1,3-cyclopentanediol. The reaction results are shown in Table 1.

[0079] Table 1 Experimental Results

[0080]

[0081] *Conversion rate refers to the ratio of the converted cyclopentadiene to the added cyclopentadiene in the reaction, which indicates the reactivity.

[0082] **Selectivity refers to the ratio of the target product 1,3-cyclopentanediol to the total product, and is a numerical value that reflects the process capability.**

Claims

1. A method for preparing 1,3-cyclopentanediol from cyclopentadiene, the method comprising the following steps: (1) Cyclopentadiene is mixed with peroxide and organic acid in a batch reactor, tubular reactor or fixed bed reactor to carry out hydroxylation reaction to obtain hydroxylated mixed intermediate product. The ratio of cyclopentadiene:peroxide:organic acid is 1:(0.1-10):(0.1-10) by molar percentage. The conditions for the hydroxylation reaction are: temperature 40-100℃, pressure 0-5.0MPa, reaction time 0.01-10.0h. (2) subjecting the hydroxylated mixed intermediate product of step (1) to rectification to obtain a hydroxylated mixed product and an aqueous organic acid solution, wherein, Optionally, after separating the water and organic acid in the organic acid aqueous solution, the separated organic acid is returned to step (1) for recycling. The distillation conditions are: 2-30 distillation column plates, 90-110℃ top temperature, 180-230℃ bottom temperature, and 0.3-1.5 bar operating pressure. (3) The hydroxylated mixed product from step (2) is subjected to hydrogenation reaction with hydrogen in a batch reactor, fixed bed reactor or tubular reactor under the action of a hydrogenation catalyst to obtain a hydrogenated mixed alcohol product. The conditions for the hydrogenation reaction are: temperature 0-300℃, hydrogen pressure 0.1-10MPa, reaction time 0.01-10.0h, and the ratio of hydrogen to the hydroxylated mixed product by molar percentage is (20-2000):

1. (4) The hydrogenated mixed alcohol product is distilled using a plate distillation column or a packed distillation column to obtain 1,3-cyclopentanediol. The distillation conditions are: 5-80 plates, 10.3-110.0 kPa pressure, 180-230℃ bottom temperature, and 50-70℃ top temperature. In step (1), the peroxide is one or more of hydrogen peroxide, peroxy-m-chlorobenzoic acid, and tert-butyl hydroperoxide; the organic acid is one or more of formic acid, acetic acid, and chloroacetic acid.

2. The method of claim 1, wherein, In step (1), the cyclopentadiene is pure cyclopentadiene or an aqueous solution of cyclopentadiene with a mass concentration of 0.01% to 100%.

3. The method as described in claim 1 or 2, wherein, In step (1), the mass space velocity when the hydroxylation reaction is carried out in a fixed bed or a tubular reactor is 0.001 h -1 - 100 h -1 .

4. The method as described in claim 1 or 2, wherein, In step (2), the separation conditions for water and organic acid are: 5-30 trays in the distillation column, 60-100℃ top temperature, 120-150℃ bottom temperature, and 0.2-1.0 bar operating pressure.

5. The method as described in claim 1 or 2, wherein, When a batch reactor is used in step (3), the reaction time is 0.01-10.0h.

6. The method as described in claim 1 or 2, wherein, When step (3) employs a fixed bed or a tubular reactor, the mass space velocity is 0.001 h -1 - 100 h -1 .

7. The method as described in claim 1 or 2, wherein, In step (3), the hydrogenation catalyst is one or a mixture of two or more of the following catalysts: (a) a supported metal catalyst in which one or a mixture of one or more of activated carbon, mesoporous carbon, silica, alumina, cerium oxide, and titanium oxide is used as a support and one or a mixture of one or more of metals Pt, Pd, Ru, Ir, Ni, Co, Cu, and Zn is supported; (b) a transition metal carbide or nitride catalyst; (c) a Raney nickel catalyst; and (d) an amorphous alloy catalyst.

8. The method as claimed in claim 1 or 2, wherein, In step (3), the hydrogenation catalyst is one or a mixture of two or more of the following catalysts: Ni / SiO2 type catalyst, Ni / Al2O3 type catalyst and Pd / Al2O3 type catalyst.

9. The method as claimed in claim 1 or 2, wherein, In step (3), the amount of hydrogenation catalyst added accounts for 0.01%-20% of the mass of the hydrogenation reaction solution.

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