Method for preparing 2-acetylfuran through catalytic dehydrogenation of 1-(2-furyl) ethanol

Abstract

The invention belongs to the technical field of organic synthesis, and particularly discloses a method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furyl) ethanol, which is characterized in that 1-(2-furyl) ethanol is used as a reaction raw material, a self-made copper-silicon catalyst is used as a catalyst, a fixed bed is used as a reactor, nitrogen is used as carrier gas, and the 2-acetylfuran is prepared by catalytic dehydrogenation reaction. Compared with the prior art, the preparation method has the advantages that the self-made copper-silicon catalyst is used as a reaction catalyst, so that the cost is reduced while the catalytic efficiency of the catalyst is not reduced; sodium silicate and copper nitrate are used as raw materials of the catalyst and are low in price and easy to obtain; the preparation method adopts a coprecipitation method, and compared with a common impregnation method for preparing the copper-silicon catalyst, the preparation method has the advantages of simple process, easy control of preparation conditions, short synthesis period and simple operation, and is suitable for industrial popularization and application. The method has the advantages of short synthetic route, high conversion rate and yield, simple operation, and no corrosion of raw materials and products to equipment, and is a safe, economic and environment-friendly 2-acetylfuran preparation method.

Description

Technical Field

[0001] The invention belongs to the technical field of organic synthesis, and particularly relates to a method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol. Background Art

[0002] 2-Acetylfuran is an important organic synthesis intermediate and food additive. 2-Acetylfuran is an important raw material for the synthesis of furan ammonium salt, an intermediate of cefuroxime. 2-Acetylfuran derivatives are also widely present in natural and processed food flavor components. They are nut and meat flavors and can be used to prepare edible flavors such as chocolate, coffee and meat flavors.

[0003] At present, the preparation process of 2-acetylfuran mainly adopts Fridel-Crafts reaction, that is, furan is used as raw material, and commonly used acetylation reagents such as acetyl chloride, acetic anhydride and acetic acid are catalyzed by acylation reaction catalyst to produce the target product. For example, the document Synthetic Communications, 38 (2), -255-268, 2008 uses acetyl chloride as acetylation reagent; patent CN112979590A and patent CN113956218A use acetic anhydride as acylation reagent; Synthesis, (13), 2165-2168, 2004 uses acetic acid as acylation reagent. The above-mentioned synthesis methods will produce a large amount of acetic acid that is difficult to recover, cause serious environmental pollution, and increase industrialization costs.

[0004] Patent CN113968832A uses 1-(2-furanyl)ethanol as raw material, TEMPO and TBN as catalysts, and oxygen as oxidant to perform catalytic oxidation reaction in an organic solvent to obtain 2-acetylfuran. This scheme avoids the use of acylating agents used in large quantities in traditional synthetic routes and obtains 2-acetylfuran through catalytic oxidation reaction, but the catalyst used is expensive and the reaction cost is high, which is not conducive to large-scale industrial promotion. Summary of the invention

[0005] In view of the deficiencies in the prior art, the object of the present invention is to provide a method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol, using a homemade copper silicon catalyst as a catalyst, which has the advantages of high conversion rate and yield, no corrosion to equipment, low catalyst price and easy preparation, simple operation, etc., and can effectively solve the problems in the background technology.

[0006] The present invention is achieved through the following technical solutions: A method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol comprises the following steps: using 1-(2-furanyl)ethanol as a reaction raw material, a self-made copper silicon catalyst as a catalyst, a fixed bed as a reactor, and nitrogen as a carrier gas to carry out a catalytic dehydrogenation reaction to prepare 2-acetylfuran.

[0007] A further improvement of the present invention is: Before the reaction, the raw material 1-(2-furanyl)ethanol is preheated before entering the reactor, and the preheating temperature is 200°C-240°C.

[0008] The catalytic dehydrogenation reaction temperature is 180-280°C.

[0009] Furthermore, the catalytic dehydrogenation reaction temperature is 220-260°C.

[0010] A further improvement of the present invention is: The copper silicon catalyst is prepared by a co-precipitation method, and the preparation process is as follows: S1: Weigh a certain mass of sodium silicate (Na2SiO3·9H2O) and copper nitrate (Cu(NO3)2·3H2O) respectively, and prepare the two into solutions of the same concentration; S2: Add the sodium silicate solution and the copper nitrate solution dropwise into a beaker filled with distilled water, stop stirring after the addition is completed, age at a constant temperature, wash, filter, and dry to obtain a catalyst precursor; S3: calcine, crush, tablet, and screen the catalyst precursor into 20-40 mesh particles to obtain catalyst particles; S4: place the catalyst particles in a reducing atmosphere at a certain temperature for reduction to obtain a copper silicon catalyst.

[0011] Furthermore, in the copper silicon catalyst, the copper loading amount is 1%-30%.

[0012] Furthermore, in the copper silicon catalyst, the copper loading amount is 5%-15%.

[0013] Furthermore, in S2, the constant temperature aging time is 2-3 hours.

[0014] Further, in S3, the catalyst precursor is heated to 500°C at a heating rate of 4°C / min in an electric furnace and calcined for 5h.

[0015] Further, in S4, the catalyst particles are reduced in a 5-10 vol% hydrogen / nitrogen mixed gas at a reduction temperature of 250-300°C. Beneficial Effects

[0016] Compared with the prior art, the present invention has the following obvious advantages: 1. The present invention adopts a homemade copper silicon catalyst as a reaction catalyst. Compared with the prior art, the cost is reduced without reducing the catalytic efficiency of the catalyst; the catalyst raw materials use sodium silicate (Na2SiO3·9H2O) and copper nitrate (Cu(NO3)2·3H2O), which are low in price and easy to obtain; the preparation method adopts a co-precipitation method, which is simple in process, easy to control preparation conditions, short in synthesis cycle, simple to operate, and suitable for industrial promotion and application compared to the commonly used impregnation method for preparing copper silicon catalysts.

[0017] 2. The present invention has a short synthetic route, high conversion rate and yield, simple operation, and both raw materials and products are non-corrosive to equipment. It is a safe, economical and environmentally friendly method for preparing 2-acetylfuran. DETAILED DESCRIPTION Example 1

[0018] Preparation of copper silicon catalyst: The mass of copper nitrate (Cu(NO3)2·3H2O) and sodium silicate (Na2SiO3·9H2O) required are calculated from the total mass and copper content of the copper silicon catalyst, and the two are prepared into solutions of the same concentration with double distilled water, and added dropwise to a beaker containing distilled water. Stirring is maintained at a constant speed during the addition process. Stirring is stopped after the addition is completed, and the catalyst is aged at a constant temperature. The catalyst precursor is then washed, filtered, and dried to obtain a catalyst precursor. The dried catalyst precursor is heated to 500°C in an electric furnace at a heating rate of 4°C / min, calcined for 5h, and then crushed, pressed, and screened into 20-40 mesh particles. The calcined catalyst particles are reduced in a 5-10 vol% hydrogen / nitrogen mixture at a reduction temperature of 250-300°C. The required copper silicon catalyst can be obtained.

[0019] The catalytic dehydrogenation experiment of 1-(2-furanyl)ethanol was carried out in a stainless steel tube reactor with an inner diameter of 14 mm. The catalyst was a homemade copper silicon catalyst with a loading amount of 80 g. The flow rate of 1-(2-furanyl)ethanol was 1.5 g / min, the nitrogen flow rate was 180 mL / min, and the reaction temperature was 220°C. Before the reaction, 1-(2-furanyl)ethanol was preheated in a preheating furnace at 200°C before entering the reactor. After the reaction, gas chromatography was used for qualitative and quantitative analysis of the product. The reaction results are shown in Table 1. Example 2

[0020] The method for preparing the copper silicon catalyst is the same as that in Example 1.

[0021] The catalytic dehydrogenation experiment of 1-(2-furanyl)ethanol was carried out in a stainless steel tube reactor with an inner diameter of 14 mm. The catalyst was a homemade copper silicon catalyst with a loading amount of 80 g. The flow rate of 1-(2-furanyl)ethanol was 1.5 g / min, the nitrogen flow rate was 180 mL / min, and the reaction temperature was 240°C. Before the reaction, 1-(2-furanyl)ethanol was preheated in a preheating furnace at 220°C before entering the reactor. After the reaction, gas chromatography was used for qualitative and quantitative analysis of the product. The reaction results are shown in Table 1. Example 3

[0022] The method for preparing the copper silicon catalyst is the same as that in Example 1.

[0023] The catalytic dehydrogenation experiment of 1-(2-furanyl)ethanol was carried out in a stainless steel tube reactor with an inner diameter of 14 mm. The catalyst was a homemade copper silicon catalyst with a loading amount of 80 g. The flow rate of 1-(2-furanyl)ethanol was 1.0 g / min, the nitrogen flow rate was 180 mL / min, and the reaction temperature was 240°C. Before the reaction, 1-(2-furanyl)ethanol was preheated in a preheating furnace at 220°C before entering the reactor. After the reaction, gas chromatography was used for qualitative and quantitative analysis of the product. The reaction results are shown in Table 1. Example 4

[0024] The method for preparing the copper silicon catalyst is the same as that in Example 1.

[0025] The catalytic dehydrogenation experiment of 1-(2-furanyl)ethanol was carried out in a stainless steel tube reactor with an inner diameter of 14 mm. The catalyst was a homemade copper silicon catalyst with a loading amount of 80 g. The flow rate of 1-(2-furanyl)ethanol was 1.5 g / min, the nitrogen flow rate was 180 mL / min, and the reaction temperature was 260°C. Before the reaction, 1-(2-furanyl)ethanol was preheated in a preheating furnace at 240°C before entering the reactor. After the reaction, gas chromatography was used for qualitative and quantitative analysis of the product. The reaction results are shown in Table 1. Example 5

[0026] The method for preparing the copper silicon catalyst is the same as that in Example 1.

[0027] The catalytic dehydrogenation experiment of 1-(2-furanyl)ethanol was carried out in a stainless steel tube reactor with an inner diameter of 14 mm. The catalyst was a homemade copper silicon catalyst with a loading amount of 80 g. The flow rate of 1-(2-furanyl)ethanol was 1.0 g / min, the nitrogen flow rate was 180 mL / min, and the reaction temperature was 260°C. Before the reaction, 1-(2-furanyl)ethanol was preheated in a preheating furnace at 240°C before entering the reactor. After the reaction, gas chromatography was used for qualitative and quantitative analysis of the product. The reaction results are shown in Table 1.

[0028] Table 1 Reaction results of Examples 1-5

[0029] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol, characterized in that: 2-acetylfuran was prepared by catalytic dehydrogenation reaction using 1-(2-furanyl)ethanol as the reaction raw material, a self-made copper-silicon catalyst as the catalyst, a fixed bed as the reactor, and nitrogen as the carrier gas.

2. The method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol according to claim 1, characterized in that: Before the reaction, the raw material 1-(2-furanyl)ethanol is preheated before entering the reactor, and the preheating temperature is 200°C-240°C.

3. The method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol according to claim 1, characterized in that: The catalytic dehydrogenation reaction temperature is 180-280°C.

4. The method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol according to claim 3, characterized in that: The catalytic dehydrogenation reaction temperature is 220-260°C.

5. The method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol according to claim 1, characterized in that: The copper-silicon catalyst is prepared by a co-precipitation method, and the preparation process is as follows: S1: Weigh a certain mass of sodium silicate and copper nitrate respectively, and prepare the two into solutions of the same concentration; S2: Add the sodium silicate solution and the copper nitrate solution dropwise into a beaker filled with distilled water, stop stirring after the addition is completed, age at a constant temperature, wash, filter, and dry to obtain a catalyst precursor; S3: calcining, crushing, tableting, and screening 20-40 mesh particles of the catalyst precursor to obtain catalyst particles; S4: placing the catalyst particles in a reducing atmosphere at a certain temperature for reduction, thereby obtaining a copper silicon catalyst.

6. The method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol according to claim 5, characterized in that: In the copper silicon catalyst, the copper loading amount is 1%-30%.

7. The method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol according to claim 6, characterized in that: In the copper silicon catalyst, the copper loading amount is 5%-15%.

8. The method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol according to claim 5, characterized in that: In S2, the constant temperature aging time is 2-3h.

9. The method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol according to claim 5, characterized in that: In S3, the catalyst precursor was heated to 500°C at a heating rate of 4°C / min in an electric furnace and calcined for 5h.

10. The method for preparing 2-acetylfuran by catalytic dehydrogenation of 1-(2-furanyl)ethanol according to claim 5, characterized in that: In S4, the catalyst particles are reduced in a 5-10 vol% hydrogen / nitrogen mixture at a reduction temperature of 250-300°C.

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