Synthetic method of 3-chloro-5-hydroxy-2-pentanone

Abstract

The present invention provides a 3-chloro-5-hydroxy-2-pentanone synthesis method, which comprises: mixing furfural, water and hydrogen, introducing the mixture into a fixed bed reactor filled with a first catalyst, and sequentially carrying out a hydroxylation reaction, a 1, 4-hydrogenation reaction and a ring-opening reaction to obtain a 5-hydroxy-3-ene-2-pentanone crude product; and mixing the 5-hydroxy-3-ene-2-pentanone crude product and hydrogen chloride gas, introducing the mixture into a fixed bed reactor filled with a second catalyst, and carrying out an addition reaction to obtain the 3-chloro-5-hydroxy-2-pentanone. The preparation method has the following advantages: the raw material furfural is low in price, and meanwhile, a relatively dangerous oxidant is prevented from being used; the process route is simple, the yield is high, and green chemical requirements are met; a fixed bed reactor is adopted for continuous catalytic preparation, the technological process is uninterrupted, and the automation degree is high; the bottleneck problem of scale limitation of kettle type reaction is solved, the reaction time is prolonged, the reaction efficiency is improved, and side reaction is inhibited to the greatest extent.

Description

Technical Field

[0001] The invention relates to the technical field of organic chemical engineering, and in particular to a method for preparing 3-chloro-5-hydroxy-2-pentanone. Background Art

[0002] Vitamin B1, also known as thiamine or anti-neuritisin, is widely used in the fields of biology and medicine. 3-Chloro-5-hydroxy-2-pentanone is a key intermediate in the synthesis of vitamin B1. In the existing relatively mature synthesis process, α-acetyl-γ-butyrolactone is used as a raw material. Under the action of chlorine and chlorination reagents, α-chloroacetyl-γ-butyrolactone is generated through a substitution reaction. The obtained α-chloroacetyl-γ-butyrolactone is then subjected to a hydrolysis reaction and a decarboxylation reaction in sequence to finally obtain 3-chloro-5-hydroxy-2-pentanone. The specific reaction process can be expressed as follows:

[0003]

[0004] As energy and environmental problems become increasingly severe, higher requirements are placed on the development of green chemistry. The common chlorination process, as one of the eighteen dangerous processes, is contrary to the current green chemistry concept. In recent years, the method of preparing 3-chloro-5-hydroxy-2-pentanone using an oxidant method has received widespread attention. This method first hydroxylates α-acetyl-γ-butyrolactone, and then undergoes a hydrolysis ring-opening reaction, a decarboxylation reaction, and a substitution reaction in sequence to finally obtain 3-chloro-5-hydroxy-2-pentanone. This preparation method usually adopts a kettle reaction, and the reaction process uses oxidizing agents such as hydrogen peroxide and oxygen instead of traditional chlorination agents, avoiding dangerous chlorination processes, which is safer and more in line with the concept of green chemistry. The specific reaction process can be expressed as follows:

[0005]

[0006] However, the oxidant method for synthesizing 3-chloro-5-hydroxy-2-pentanone also has many problems, such as long reaction time, low synthesis efficiency, high system pressure during reaction, certain safety hazards for industrial large-scale production, inconvenient application of reaction catalysts, and low catalyst utilization efficiency. Summary of the invention

[0007] The main purpose of the present invention is to provide a method for synthesizing 3-chloro-5-hydroxy-2-pentanone, which solves the problems in the prior art of too long reaction time, unsafe reaction conditions, short life of the catalyst used in the reaction, inconvenient application, and difficulty in realizing large-scale production of 3-chloro-5-hydroxy-2-pentanone when synthesizing the vitamin B1 intermediate 3-chloro-5-hydroxy-2-pentanone.

[0008] In order to solve the above problems, the present invention provides a method for synthesizing 3-chloro-5-hydroxy-2-pentanone. The preparation method comprises the following steps: step (1), mixing furfural, water and hydrogen to obtain a first mixed material; step (2), passing the first mixed material into a first fixed bed reactor equipped with a first catalyst, and sequentially performing a hydroxylation reaction, a 1,4-hydrogenation reaction and a ring-opening reaction to obtain a crude 5-hydroxy-3-ene-2-pentanone; step (3), mixing the crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas to obtain a second mixed material; step (4), passing the second mixed material into a second fixed bed reactor equipped with a second catalyst, and performing an addition reaction to obtain 3-chloro-5-hydroxy-2-pentanone.

[0009] Furthermore, the first catalyst is a metal acid-modified molecular sieve, which includes an acid-modified molecular sieve and a first active metal loaded thereon; preferably, the first active metal is one or more of Ru, Fe, Pd, Mn, Zn, Co, Rh and Al; preferably, the metal acid-modified molecular sieve is one or more of solid acid-modified Ru@ZSM-5, solid acid-modified Fe@ZSM-5, solid acid-modified Co@ZSM-5 and solid acid-modified Mn@ZSM-5.

[0010] Furthermore, the second catalyst is a metal-loaded molecular sieve, which includes a molecular sieve and a second active metal loaded thereon; preferably, the second active metal is one or more of Ru, Fe, Pd, Mn, Zn, Co, Rh and Al; preferably, the metal-loaded molecular sieve is one or more of Co@CMK-3, Ru@CMK-3, Fe@CMK-3, Mn@CMK-3, Al@CMK-3 and Pd@CMK-3.

[0011] Furthermore, in step (1), the weight ratio of furfural to water is 1:(1.1-1.5).

[0012] Furthermore, in step (1), the molar ratio of furfural to hydrogen is 1:(2.0-2.1).

[0013] Furthermore, the reaction temperature in the first fixed bed reactor in step (2) is 70 to 90° C.; preferably, the reaction pressure in the first fixed bed reactor in step (2) is 1.0 to 1.5 MPa.

[0014] Furthermore, the reaction temperature in the second fixed bed reactor in step (4) is 65-80° C.; preferably, the reaction pressure in the second fixed bed reactor in step (4) is 0.1-0.8 MPa.

[0015] Furthermore, in step (3), the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas in the crude 5-hydroxy-3-ene-2-pentanone is 1:(1.1-1.3).

[0016] Furthermore, in step (2), the mass space velocity of the first mixed material in the first fixed bed reactor is 1 to 20 hr -1 .

[0017] Furthermore, in step (4), the mass space velocity of the second mixed material in the second fixed bed reactor is 1 to 6 hr -1 .

[0018] The invention provides a method for synthesizing 3-chloro-5-hydroxy-2-pentanone. The method uses furfural as a raw material, and sequentially performs hydroxylation reaction, 1,4-hydrogenation reaction, and ring-opening reaction with hydrogen and water to obtain a crude 5-hydroxy-3-ene-2-pentanone; the obtained crude 5-hydroxy-3-ene-2-pentanone is then mixed with hydrogen chloride gas and subjected to addition reaction to obtain 3-chloro-5-hydroxy-2-pentanone. The method for preparing 3-chloro-5-hydroxy-2-pentanone has the following advantages: (1) the raw material furfural is cheap, which reduces the excessive dependence on fossil resources when synthesizing low-carbon alcohols, and avoids the use of more dangerous oxidants as reaction raw materials, so that the safety factor is higher; (2) the process route is simple, the yield is high, and it meets the requirements of green synthetic chemistry; (3) a fixed bed reactor is used for continuous catalytic preparation, the process is carried out uninterruptedly, and the degree of automation is high; (4) the bottleneck problem of scale limitation of intermittent reactor reaction is solved, the reaction time and reaction efficiency are greatly improved, and the side reaction is suppressed to the greatest extent. DETAILED DESCRIPTION

[0019] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0020] As described in the background technology section, vitamin B1 has a wide range of uses, and 3-chloro-5-hydroxy-2-pentanone is a key intermediate for the synthesis of vitamin B1. The chlorination process of using chlorine and chlorination reagents to prepare 3-chloro-5-hydroxy-2-pentanone is not only dangerous, but also inconsistent with the concept of green chemistry; while the use of an oxidant method to prepare 3-chloro-5-hydroxy-2-pentanone has the problems of long reaction time, low synthesis efficiency, high system pressure during the reaction, potential safety hazards, and is not conducive to industrial large-scale production. In addition, the conventional kettle reaction method has the problems of inconvenient application of reaction catalysts and low catalyst utilization efficiency.

[0021] In order to solve the above problems, the present application provides a method for synthesizing 3-chloro-5-hydroxy-2-pentanone, which comprises the following steps: step (1), mixing furfural, water and hydrogen to obtain a first mixed material; step (2), passing the first mixed material into a first fixed bed reactor equipped with a first catalyst, and sequentially performing a hydroxylation reaction, a 1,4-hydrogenation reaction and a ring-opening reaction to obtain a crude 5-hydroxy-3-ene-2-pentanone; step (3), mixing the crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas to obtain a second mixed material; step (4), passing the second mixed material into a second fixed bed reactor equipped with a second catalyst, and performing an addition reaction to obtain 3-chloro-5-hydroxy-2-pentanone.

[0022] Specifically, the method for preparing 3-chloro-5-hydroxy-2-pentanone first mixes furfural, water and hydrogen, and passes them into a first fixed bed reactor. Under the action of a first catalyst (Cat 1) and hydrogen and water, the aldehyde group of furfural undergoes a hydroxylation reaction, and the unsaturated bonds on the aromatic ring of furfural undergo a 1,4-hydrogenation reaction to generate dihydrofurfuryl alcohol. Then, dihydrofurfuryl alcohol is further ring-opened to generate 5-hydroxy-3-ene-2-pentanone, and a crude 5-hydroxy-3-ene-2-pentanone is obtained. The present application further mixes the obtained crude 5-hydroxy-3-ene-2-pentanone with hydrogen chloride gas and passes them into a second fixed bed reactor. Under the action of a second catalyst (Cat 2), 5-hydroxy-3-ene-2-pentanone and hydrogen chloride undergo an addition reaction to obtain the final product 3-chloro-5-hydroxy-2-pentanone. The specific reaction process of the reaction can be expressed as follows:

[0023]

[0024] In particular, the present application uses furfural as a raw material when preparing 3-chloro-5-hydroxy-2-pentanone. Different from the traditional preparation method of using α-acetyl-γ-butyrolactone as a raw material and using a chlorination process or an oxidant method to prepare 3-chloro-5-hydroxy-2-pentanone, the raw material used in the synthesis of 3-chloro-5-hydroxy-2-pentanone in the present application is furfural, which is not only cheap, but also widely available. In addition, the synthesis and preparation process of 3-chloro-5-hydroxy-2-pentanone using furfural as a raw material only requires hydrogen, water, hydrogen chloride gas and a catalyst. The reaction raw materials are also cheap and have a higher safety factor, avoiding the use of highly dangerous chemical reagents such as chlorine and hydrogen peroxide. In particular, in the synthesis route of the present application, the catalyst used can also be reused for a long time, and the overall reaction efficiency can also be significantly improved. Therefore, when the preparation method is applied to industrial large-scale production, it can not only reduce production costs in many aspects, but also make the production process safer and greener.

[0025] In addition, the present application adopts a continuous fixed bed reaction system with excellent mass transfer, heat transfer and material molecular mixing performance, which replaces the traditional reactor and realizes continuous synthesis from raw materials to products, with high automation, short reaction time and high reaction efficiency. The entire process flow from the first mixed material to the first stage of hydroxylation reaction, 1,4-hydrogenation reaction, and ring-opening reaction to generate 5-hydroxy-3-ene-2-pentanone, and then from the second mixed material to the second stage of addition reaction, finally generating 3-chloro-5-hydroxy-2-pentanone, can realize the process uninterruptedly in the production process, greatly reducing the number of operators and labor intensity, and can significantly reduce production costs. In addition, it also solves the bottleneck problem of intermittent kettle reaction scale limitation, which is conducive to industrial large-scale production.

[0026] In summary, the method for synthesizing 3-chloro-5-hydroxy-2-pentanone provided by the present invention has the advantages of easy availability of raw materials, mild reaction conditions, high synthesis efficiency and a simpler process route, and is suitable for large-scale industrial production.

[0027] In a preferred embodiment, the first catalyst is a metal acid-modified molecular sieve, which includes an acid-modified molecular sieve and a first active metal loaded thereon. The first catalyst can shorten the reaction time of this stage during the reaction process. In particular, the use of an acid-modified molecular sieve loaded with an active metal as a catalyst can further promote the hydroxylation reaction, 1,4-hydrogenation reaction, and ring-opening reaction of furfural with water and hydrogen. Loading the active metal on the acid-modified molecular sieve can facilitate the entire reaction process. Preferably, the first active metal is one or more of Ru, Fe, Pd, Mn, Zn, Co, Rh, and Al, and the above-mentioned types of active metals have a better promoting effect on the reaction. Preferably, the metal acid-modified molecular sieve is one or more of solid acid-modified Ru@ZSM-5, solid acid-modified Fe@ZSM-5, solid acid-modified Co@ZSM-5, and solid acid-modified Mn@ZSM-5. The solid acid modified metal molecular sieve is to react ZSM-5 molecular sieve with sulfonic acid or sulfuric acid to form a solid acid carrier, and then load the corresponding metal to obtain the solid acid modified metal molecular sieve. These molecular sieves can be purchased on the market and can promote the reaction process. The molecular sieve in which the active metal is loaded in the acid-modified molecular sieve can be any molecular sieve capable of loading the active metal, and the preferred molecular sieves can make the reaction effect better.

[0028] In a preferred embodiment, the second catalyst is a metal-loaded molecular sieve, which includes a molecular sieve and a second active metal loaded thereon. The second catalyst can catalyze 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas to better perform addition reaction during the reaction. The metal loading on the molecular sieve can be more convenient for the entire reaction process. The use of the catalyst can also greatly shorten the reaction time at this stage and improve the reaction efficiency. Preferably, the second active metal is one or more of Ru, Fe, Pd, Mn, Zn, Co, Rh and Al, and the above-mentioned active metal has a better promoting effect on the reaction. Preferably, the metal-loaded molecular sieve is one or more of Co@CMK-3, Ru@CMK-3, Fe@CMK-3, Mn@CMK-3, Al@CMK-3 and Pd@CMK-3, and these molecular sieves can be purchased on the market, which can promote the reaction process.

[0029] In a preferred embodiment, the weight ratio of furfural to water in step (1) is 1:(1.1-1.5), and the molar ratio of furfural to hydrogen in step (1) is 1:(2.0-2.1). In the process of synthesizing 3-chloro-5-hydroxy-2-pentanone, furfural, water and hydrogen are sequentially subjected to hydroxylation reaction, 1,4-hydrogenation reaction and ring-opening reaction under the action of the first catalyst, and finally 5-hydroxy-3-ene-2-pentanone is obtained. The furfural, water and hydrogen participate together to complete the reaction, and the weight ratio of furfural to water is controlled to be 1:(1.1-1.5), and the molar ratio of furfural to hydrogen is controlled to be 1:(2.0-2.1). The above ratios help the reaction to be more complete and improve the conversion rate of the reaction.

[0030] In a preferred embodiment, the reaction temperature in the first fixed bed reactor in step (2) is 70-90° C.; preferably, the reaction pressure in the first fixed bed reactor in step (2) is 1.0-1.5 MPa. In the process of furfural reacting with water and hydrogen to generate 5-hydroxy-3-ene-2-pentanone intermediate, controlling the reaction temperature and reaction pressure in the first fixed bed reactor within the above range can further increase the reaction rate of the reaction process, thereby shortening the reaction time of the entire synthesis process and improving the synthesis efficiency.

[0031] In a preferred embodiment, the reaction temperature in the second fixed bed reactor in step (4) is 65-80° C.; preferably, the reaction pressure in the second fixed bed reactor in step (4) is 0.1-0.8 MPa. In the process of generating 3-chloro-5-hydroxy-2-pentanone by the reaction of 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas, controlling the reaction temperature and reaction pressure in the second fixed bed reactor within the above range can further increase the reaction rate of this reaction process, further shorten the overall reaction time, and improve the synthesis efficiency.

[0032] In a preferred embodiment, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas in the crude 5-hydroxy-3-ene-2-pentanone in step (3) is 1:(1.1-1.3). 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas undergo an addition reaction under the action of the second catalyst. Controlling the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas within the range of 1:(1.1-1.3) can make the addition reaction in the reaction process more complete.

[0033] In a preferred embodiment, the mass space velocity of the first mixed material in the first fixed bed reactor in step (2) is 1 to 20 hr -1 The mass space velocity of the reaction liquid determines the mass of reactants passing through a unit mass of the catalyst per unit time, that is, it determines the mixed contact between the mixed liquid of furfural, water and hydrogen and the first catalyst. Controlling the mass space velocity of the first mixed material in step (2) within the above range is conducive to a more complete reaction.

[0034] In a preferred embodiment, the mass space velocity of the second mixed material in the second fixed bed reactor in step (3) is 1 to 6 hr -1 The mass space velocity of the reaction liquid in step (3) determines the mixed contact between 5-hydroxy-3-ene-2-pentanone, the hydrogen chloride gas mixed liquid and the second catalyst. Controlling the mass space velocity of the second mixed material in step (3) within the above range further promotes a more complete reaction.

[0035] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0036] In order to understand this plan more clearly, it is necessary to further explain here:

[0037] Regarding the source of reagents: the first catalyst solid acid modified Ru@ZSM-5, solid acid modified Fe@ZSM-5, solid acid modified Co@ZSM-5, solid acid modified Mn@ZSM-5, were all purchased, and were all sulfuric acid modified molecular sieves; the second catalyst Co@CMK-3, Ru@CMK-3, Fe@CMK-3, Mn@CMK-3, Al@CMK-3, and Pd@CMK-3 were also purchased.

[0038] About data testing method:

[0039] Calculation of furfural conversion rate: Take a sample from the product storage buffer tank at the outlet of the first fixed bed reactor, detect the molar content of 5-hydroxy-3-ene-2-pentanone in the sample by gas phase detection method as x, and the molar content of the remaining furfural as y, and the conversion rate of furfural is x / (x+y);

[0040] Calculation method for the yield of 3-chloro-5-hydroxy-2-pentanone: the molar amount of furfural introduced is recorded as x, the molar amount of 3-chloro-5-hydroxy-2-pentanone obtained is recorded as z, and the yield of 3-chloro-5-hydroxy-2-pentanone is z / x;

[0041] Content test of 5-hydroxy-3-ene-2-pentanone and 3-chloro-5-hydroxy-2-pentanone: taking a sample from the product storage buffer tank at the outlet of the first fixed bed reactor, and detecting the content of 5-hydroxy-3-ene-2-pentanone in the sample by a gas chromatography-mass spectrometer detection method; taking a sample from the product storage buffer tank at the outlet of the second fixed bed reactor, and detecting the content of 3-chloro-5-hydroxy-2-pentanone in the sample by a gas chromatography-mass spectrometer detection method;

[0042] Calculation of catalyst life: Taking the activity and selectivity of the catalyst at the beginning of use as the benchmark, when the activity and selectivity of the catalyst during use drop to less than 90% of the initial activity and selectivity, the catalyst is considered to be deactivated, and this period of time is the life of the catalyst.

[0043] Example 1

[0044] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 99.3%.

[0045] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas was 1:1.12), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0046] Example 2

[0047] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.06 mL / min and 19.14 mL / min respectively through metering pumps to obtain a first mixed material (at this flow rate, the molar ratio of furfural to hydrogen was 1:2.0, and the weight ratio of furfural to water was 1:1.1). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 90° C., the pressure was 1.0 MPa, and the mass space velocity was 1.0 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 99.1%.

[0048] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into a mixer through metering pumps at flow rates of 38 mg / min and 4.44 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas was 1:1.1), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Mn@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 65° C., the reaction pressure was 0.1 MPa, and the mass space velocity was 1.0 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0049] Example 3

[0050] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.47 mL / min and 26.1 mL / min respectively through metering pumps to obtain a first mixed material (at this flow rate, the molar ratio of furfural to hydrogen was 1:2.1, and the weight ratio of furfural to water was 1:1.5). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 90° C., the pressure to be 1.0 MPa, and the mass space velocity to be 20.0 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 98.8%.

[0051] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into a mixer through metering pumps at flow rates of 38 mg / min and 5.55 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas is 1:1.3), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Pd@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 65° C., the reaction pressure was 0.1 MPa, and the mass space velocity was 6.0 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0052] Example 4

[0053] The difference from Example 1 is that the flow rate of hydrogen through the metering pump is adjusted to 10 mL / min (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen is 1:2.48).

[0054] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 10 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.48, and the weight ratio of furfural to water was 1:1.15). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 96.7%.

[0055] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas was 1:1.13), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0056] Example 5

[0057] The difference from Example 1 is that the flow rate of hydrogen through the metering pump is adjusted to 7 mL / min (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen is 1:1.736).

[0058] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 7 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:1.736, and the weight ratio of furfural to water was 1.15). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 99.78%, and the content of 5-hydroxy-3-ene-2-pentanone is 90.13%.

[0059] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas was 1:1.24), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0060] Example 6

[0061] The difference from Example 1 is that the flow rate of water through the metering pump is adjusted to 30 mL / min (at this flow rate of the metering pump, the mass ratio of furfural to water is 1:1.72).

[0062] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 30 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.72). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 97.27%.

[0063] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas was 1:1.148), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0064] Example 7

[0065] The difference from Example 1 is that the flow rate of water through the metering pump is adjusted to 15 mL / min (at this flow rate of the metering pump, the mass ratio of furfural to water is 1:0.86).

[0066] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 15 mL / min respectively through metering pumps to obtain a first mixed material (at this flow rate, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:0.86). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 99.10%, and the content of 5-hydroxy-3-ene-2-pentanone is 96.80%.

[0067] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas is 1.164), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0068] Example 8

[0069] The difference from Example 1 is that the reaction temperature of the first fixed bed reactor is adjusted to 110°C.

[0070] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min through metering pumps, respectively, to obtain a first mixed material (at this flow rate, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 110° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 94.6%.

[0071] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas was 1:1.18), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0072] Example 9

[0073] The difference from Example 1 is that the reaction temperature of the first fixed bed reactor is adjusted to 50°C.

[0074] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 50° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 98.70%, and the content of 5-hydroxy-3-ene-2-pentanone is 93.9%.

[0075] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas was 1:1.3), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0076] Example 10

[0077] The difference from Example 1 is that the pressure of the first fixed bed reactor is adjusted to 2.0 MPa.

[0078] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min through metering pumps, respectively, to obtain a first mixed material (at this flow rate, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 2.0 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 99.80%, and the content of 5-hydroxy-3-ene-2-pentanone is 96.1%.

[0079] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas was 1:1.16), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0080] Embodiment 11

[0081] The difference from Example 1 is that the pressure of the first fixed bed reactor is adjusted to 0.5 MPa.

[0082] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 0.5 MPa, and the mass space velocity was 1.085 hr -1After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 98.70%, and the content of 5-hydroxy-3-ene-2-pentanone is 95.7%.

[0083] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas was 1:1.18), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0084] Example 12

[0085] The difference from Example 1 is that the first catalyst is solid acid modified Fe@ZSM-5, and the second catalyst is Ru@CMK-3.

[0086] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min respectively through metering pumps to obtain a first mixed material (at this flow rate, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Fe@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 98.5%.

[0087] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into a mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas was 1:1.13), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Ru@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0088] Example 13

[0089] The difference from Example 1 is that the first catalyst is solid acid modified Co@ZSM-5, and the second catalyst is Fe@CMK-3.

[0090] Furfural, hydrogen and water were respectively introduced into a mixer through a metering pump at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Co@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 98.2%.

[0091] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into a mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas was 1:1.137), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Fe@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0092] Embodiment 14

[0093] The difference from Example 1 is that the first catalyst is solid acid modified Mn@ZSM-5, and the second catalyst is Al@CMK-3.

[0094] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Mn@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 97.9%.

[0095] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into a mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas was 1:1.14), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Al@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0096] Embodiment 15

[0097] The difference from Example 1 is that the flow rate of the hydrogen chloride gas through the metering pump is adjusted to 7 mL / min (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas is 1:1.57).

[0098] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 99.30%.

[0099] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer at flow rates of 38 mg / min and 7 mL / min through metering pumps to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas was 1:1.57), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0100] Example 16

[0101] The difference from Example 1 is that the flow rate of the hydrogen chloride gas through the metering pump is adjusted to 4 mL / min (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas is 1:0.899).

[0102] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product liquid storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 99.30%.

[0103] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 4 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas was 1:0.899), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 80° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0104] Embodiment 17

[0105] The difference from Example 1 is that the reaction temperature of the second fixed bed reactor is adjusted to 105°C.

[0106] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 99.3%.

[0107] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas was 1:1.12), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 105° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0108] Embodiment 18

[0109] The difference from Example 1 is that the reaction temperature of the second fixed bed reactor is adjusted to 45°C.

[0110] Furfural, hydrogen and water were introduced into a mixer at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min respectively through a metering pump to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 99.3%.

[0111] The crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas obtained above were respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas was 1:1.12), and the second mixed material was introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor was controlled to be 45° C., the reaction pressure was 0.8 MPa, and the mass space velocity was 1.075 hr -1After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0112] Embodiment 19

[0113] The difference from Example 1 is that the pressure of the second fixed bed reactor is adjusted to 1.5 MPa.

[0114] 17.4 g of furfural, hydrogen and water were respectively introduced into a mixer through a metering pump at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 99.3%.

[0115] The crude 5-hydroxy-3-ene-2-pentanone obtained above (the content of 5-hydroxy-3-ene-2-pentanone is 18 g) and hydrogen chloride gas are respectively introduced into the mixer through metering pumps at flow rates of 38 mg / min and 5 mL / min to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas is 1:1.12), and the second mixed material is introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor is controlled to be 80° C., the reaction pressure is 1.5 MPa, and the mass space velocity is 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0116] Embodiment 20

[0117] The difference from Example 1 is that the pressure of the second fixed bed reactor is adjusted to 0.02 MPa.

[0118] 17.4 g of furfural, hydrogen and water were respectively introduced into a mixer through a metering pump at flow rates of 15 mL / min, 8.4 mL / min and 20 mL / min to obtain a first mixed material (at this flow rate of the metering pump, the molar ratio of furfural to hydrogen was 1:2.08, and the weight ratio of furfural to water was 1:1.149). The first mixed material was introduced into a first fixed bed reactor filled with 40 g of a first catalyst (solid acid modified Ru@ZSM-5) for reaction, and the reaction temperature of the first fixed bed reactor was controlled to be 70° C., the pressure was 1.5 MPa, and the mass space velocity was 1.085 hr -1 After the reaction is completed, the obtained crude 5-hydroxy-3-ene-2-pentanone flows out from the outlet of the fixed bed reactor and is collected in the product storage buffer tank. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 100%, and the content of 5-hydroxy-3-ene-2-pentanone is 99.3%.

[0119] The crude 5-hydroxy-3-ene-2-pentanone obtained above (the 5-hydroxy-3-ene-2-pentanone content is 18 g) and hydrogen chloride gas are respectively introduced into the mixer at flow rates of 38 mg / min and 5 mL / min through metering pumps to obtain a second mixed material (at this flow rate of the metering pump, the molar ratio of 5-hydroxy-3-ene-2-pentanone to hydrogen chloride gas is 1:1.12), and the second mixed material is introduced into a second fixed bed reactor filled with 40 g of the second catalyst (Co@CMK-3) for reaction, and the reaction temperature of the second fixed bed reactor is controlled to be 80° C., the reaction pressure is 0.02 MPa, and the mass space velocity is 1.075 hr -1 After the reaction was completed, the obtained 3-chloro-5-hydroxy-2-pentanone flowed out from the outlet of the fixed bed reactor and was collected in the product storage buffer tank. The obtained 3-chloro-5-hydroxy-2-pentanone was tested, and the results are shown in Table 1.

[0120] Comparative Example 1

[0121] Comparative Example 1: 3-chloro-5-hydroxy-2-pentanone was prepared by an intermittent operation method.

[0122] Take 108g H2O, 96g furfural (1.0mol), 40g solid acid modified Ru@ZSM-5 catalyst, add them into a 500mL tetrafluoroethylene lined closed autoclave with stirring and cooling reflux device, then introduce 4.2g hydrogen into the autoclave, maintain the reaction temperature in the autoclave at 90℃, the pressure is about 1.5MPa, stir the reaction for 10h, the reaction is completed, filter out the solid acid modified Ru@ZSM-5 catalyst for application. After sampling and separating the gas components through a gas-liquid separator, the conversion rate of furfural is measured to be 91.6%, and the content of 5-hydroxy-3-ene-2-pentanone is 84.3%.

[0123] After the reaction is completed, the temperature in the autoclave is slowly reduced to 25°C, the gas in the autoclave is emptied, and the pressure is reduced to normal pressure. The reaction solution is transferred to a 500mL closed autoclave lined with tetrafluoroethylene with a stirring and cooling reflux device, 40g of the second catalyst Co@CMK-3 is added, and then 37.5g of hydrogen chloride gas is introduced into the autoclave, the reaction temperature in the autoclave is maintained at 80°C, the pressure is about 0.8MPa, and the reaction is continued for 4h under stirring. After the reaction is completed, it is cooled to room temperature, the exhaust port of the autoclave is connected to the tail gas absorption device and opened, and the Co@CMK-3 catalyst is filtered out after emptying, and the obtained 3-chloro-5-hydroxy-2-pentanone is tested. The results are shown in Table 1.

[0124] Table 1

[0125]

[0126]

[0127] Examples 1 to 3 and Examples 12 to 14 all use the scheme for preparing 3-chloro-5-hydroxy-2-pentanone described in the present application, and control the parameters of each synthesis step within the preferred range, and the conversion rate of furfural to 5-hydroxy-3-ene-2-pentanone and the conversion rate of furfural to 3-chloro-5-hydroxy-2-pentanone are maintained at a very high level, wherein the conversion rate of furfural to 3-chloro-5-hydroxy-2-pentanone can reach up to 96.43%. In addition, the method for preparing 3-chloro-5-hydroxy-2-pentanone can control the reaction time to be greatly shortened, has high selectivity, and the product only contains water and does not need to be subjected to extraction and separation operations, and can proceed to the next step of reaction, which greatly reduces the operation process, has good safety, is easy to industrialize, and can also control the service life of the catalyst at a high level. In Examples 4 to 11 and 15 to 20, in the process of synthesizing 5-hydroxy-3-ene-2-pentanone, the preparation method of the present invention is also used. Even if some parameters in the control examples are not within the preferred range, the furfural conversion rate and the life of the catalyst are still at a high level. In short, by using the preparation method of the present invention and controlling the preparation conditions within the preferred range of the present invention, not only can the conversion rate of furfural into 3-chloro-5-hydroxy-2-pentanone be at a high level, but the first catalyst and the second catalyst can also reach the use standard for a long time.

[0128] In contrast, in Comparative Example 1, a kettle reaction method was used to synthesize 5-hydroxy-3-ene-2-pentanone. Although the reaction conditions were the same, the reaction time was long, the operation was discontinuous, and a large process energy consumption was required. In addition, the conversion rate of furfural to 5-hydroxy-3-ene-2-pentanone and the final conversion rate to 3-chloro-5-hydroxy-2-pentanone were also unsatisfactory, and the catalyst used could not reach the conventional use standard after only 20 repetitions.

[0129] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for synthesizing 3-chloro-5-hydroxy-2-pentanone, It is characterized in that The method comprises the following steps: Step (1), mixing furfural, water and hydrogen to obtain a first mixed material; Step (2), passing the first mixed material into a first fixed bed reactor containing a first catalyst, and sequentially performing a hydroxylation reaction, a 1,4-hydrogenation reaction, and a ring-opening reaction to obtain a crude 5-hydroxy-3-ene-2-pentanone; Step (3), mixing the crude 5-hydroxy-3-ene-2-pentanone and hydrogen chloride gas to obtain a second mixed material; Step (4), passing the second mixed material into a second fixed bed reactor containing a second catalyst to carry out an addition reaction to obtain the 3-chloro-5-hydroxy-2-pentanone.

2. The method for synthesizing 3-chloro-5-hydroxy-2-pentanone according to claim 1, It is characterized in that The first catalyst is a metal acid-modified molecular sieve, which includes the acid-modified molecular sieve and a first active metal supported thereon; Preferably, the first active metal is one or more of Ru, Fe, Pd, Mn, Zn, Co, Rh and Al; Preferably, the metal acid-modified molecular sieve is one or more of solid acid-modified Ru@ZSM-5, solid acid-modified Fe@ZSM-5, solid acid-modified Co@ZSM-5 and solid acid-modified Mn@ZSM-5.

3. The method for synthesizing 3-chloro-5-hydroxy-2-pentanone according to claim 1, It is characterized in that The second catalyst is a metal-supported molecular sieve, which comprises a molecular sieve and a second active metal supported thereon; Preferably, the second active metal is one or more of Ru, Fe, Pd, Mn, Zn, Co, Rh and Al; Preferably, the metal-loaded molecular sieve is one or more of Co@CMK-3, Ru@CMK-3, Fe@CMK-3, Mn@CMK-3, Al@CMK-3 and Pd@CMK-3.

4. The method for synthesizing 3-chloro-5-hydroxy-2-pentanone according to any one of claims 1 to 3, It is characterized in that The weight ratio of furfural to water in the step (1) is 1:(1.1-1.5).

5. The method for synthesizing 3-chloro-5-hydroxy-2-pentanone according to any one of claims 1 to 3, It is characterized in that The molar ratio of furfural to hydrogen in the step (1) is 1:(2.0-2.1).

6. The method for synthesizing 3-chloro-5-hydroxy-2-pentanone according to any one of claims 1 to 3, It is characterized in that The reaction temperature in the first fixed bed reactor in the step (2) is 70-90° C.; preferably, the reaction pressure in the first fixed bed reactor in the step (2) is 1.0-1.5 MPa.

7. The method for synthesizing 3-chloro-5-hydroxy-2-pentanone according to any one of claims 1 to 3, It is characterized in that The reaction temperature in the second fixed bed reactor in the step (4) is 65-80° C.; preferably, the reaction pressure in the second fixed bed reactor in the step (4) is 0.1-0.8 MPa.

8. The method for synthesizing 3-chloro-5-hydroxy-2-pentanone according to any one of claims 1 to 7, It is characterized in that The molar ratio of 5-hydroxy-3-ene-2-pentanone in the crude 5-hydroxy-3-ene-2-pentanone in the step (3) to the hydrogen chloride gas is 1:(1.1-1.3).

9. The method for synthesizing 3-chloro-5-hydroxy-2-pentanone according to any one of claims 1 to 7, It is characterized in that The mass space velocity of the first mixed material in the first fixed bed reactor in the step (2) is 1 to 20 hr -1 .

10. The method for synthesizing 3-chloro-5-hydroxy-2-pentanone according to any one of claims 1 to 7, It is characterized in that The mass space velocity of the second mixed material in the second fixed bed reactor in step (4) is 1 to 6 hr -1 .

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