Catalyst composition, preparation method, use and method for synthesizing 2-pentanone

Abstract

The present invention belongs to the field of organic synthesis, and specifically relates to a catalyst composition, a preparation method, a use, and a method for synthesizing 2-pentanone. The present invention uses acetic acid and n-butyric acid as raw materials in a fixed bed reactor, and uses a catalyst composition to efficiently produce 2-pentanone; the catalyst composition uses copper oxide, cerium oxide and lanthanum oxide as active components, and ZrO2-Al2O3 as a catalyst carrier. The method for synthesizing 2-pentanone using the catalyst composition of the present invention has the advantages of mild reaction conditions, high selectivity, high product yield, and easy continuous production, and has important application value in the field of organic synthesis.

Description

Technical Field

[0001] The invention belongs to the field of organic synthesis, and specifically relates to a catalyst composition, a preparation method, an application and a method for synthesizing 2-pentanone. Background Art

[0002] 2-Pentanone, also known as methyl propyl ketone, has a special smell and is an excellent solvent and synthetic intermediate. It can be used to synthesize the vasodilator drug Virga. At the same time, 2-pentanone is also an important organic chemical raw material, mainly used as paint, ink, pesticide, pharmaceutical intermediate, flavor ingredient, etc. It is widely used in chemical synthesis, food, cosmetics and other industrial fields.

[0003] At present, the mainstream preparation processes in industry are intermittent and continuous. Chinese patent CN115850042A adopts an intermittent reactor process and uses a platinum-based catalyst for hydrogenation of 2-methylfuran to prepare 2-pentanone. This process has the disadvantages of toxic raw materials and unfriendly environment. In addition, the use of precious metals as catalysts has high costs and is not conducive to large-scale production. The intermittent process has problems such as complex operation, low production efficiency, and unstable product quality. In the continuous reaction, the fixed bed process has the advantages of stable reaction conditions, high production efficiency, and easy automatic control. Chinese patent CN110694626A adopts a fixed bed process and discloses a MCuO / ZrO2 / Al2O3 composite catalyst for ethanol synthesis of 2-pentanone. The selectivity of 2-pentanone in this process is 68%, but the catalyst preparation process is complicated. In addition, Chinese patent CN112898142 A discloses a method for preparing 2-pentanone from ethanol and acetone using a cerium oxide-based catalyst, and the reaction temperature is 200-350 ° C, but the raw material conversion rate of this method is low. Based on this, Chinese patent CN113559843 A proposes a new method for synthesizing 2-pentanone, using a solid mixed metal oxide catalyst, acetic acid and n-butyric acid as raw materials to synthesize 2-pentanone in one step, with a conversion rate of 90-95% and a selectivity of 2-pentanone of 50-60%.

[0004] Based on the above examples, in order to simplify the production process and improve the catalytic efficiency, it is urgent to develop a 2-pentanone synthesis process with mild reaction conditions, high raw material conversion rate, good selectivity, high product yield, and easy continuous production. Summary of the invention

[0005] In view of the problems of the prior art, the present invention provides a catalyst composition, a preparation method, a use and a method for synthesizing 2-pentanone.

[0006] A catalyst composition comprising the following raw materials in parts by weight:

[0007] 15-25 parts of copper oxide,

[0008] 5-10 parts of cerium oxide,

[0009] 1-5 parts of lanthanum oxide,

[0010] 60-80 parts of zirconium oxide-aluminum oxide composite carrier.

[0011] Preferably, 20 parts of copper oxide,

[0012] 6 parts of cerium oxide,

[0013] 4 parts of lanthanum oxide,

[0014] 70 parts of zirconium oxide-aluminum oxide composite carrier.

[0015] Preferably, its preparation method comprises the following steps:

[0016] Step 1: calcining the zirconium oxide-aluminum oxide composite carrier;

[0017] Step 2: Impregnate Cu(NO3)2•3H2O solution, Ce(NO3)3•6H2O solution and La(NO3)3•6H2O solution on the calcined zirconium oxide-alumina composite carrier, dry and calcine to obtain.

[0018] Preferably, in step 1, the calcination temperature is 200-600°C and the calcination time is 2-10 h;

[0019] And / or, in step 2, the impregnation time is 24-36 h; the drying temperature is 60-150° C., and the drying time is 2-24 h; the calcination temperature is 200-1000° C., and the calcination time is 2-24 h.

[0020] The present invention also provides a method for preparing the catalyst composition, comprising the following steps:

[0021] Step 1: calcining the zirconium oxide-aluminum oxide composite carrier;

[0022] Step 2: Impregnate Cu(NO3)2•3H2O solution, Ce(NO3)3•6H2O solution and La(NO3)3•6H2O solution on the calcined zirconium oxide-alumina composite carrier, dry and calcine to obtain.

[0023] The present invention also provides use of the catalyst composition as a catalyst for synthesizing 2-pentanone.

[0024] The present invention also provides a method for synthesizing 2-pentanone, comprising the following reaction:

[0025] Acetic acid and n-butyric acid are introduced into a reactor containing the above catalyst composition to react and prepare 2-pentanone. The reaction formula is:

[0026] .

[0027] Preferably, the catalyst composition is filled in the reactor with a thickness of 10-25 cm; the reaction temperature is 220-280° C., the reaction pressure is 0.4-1.8 MPa; and the mass ratio of acetic acid to n-butyric acid is 1-4:1.

[0028] Preferably, the catalyst composition is filled in the reactor with a thickness of 20 cm; the reaction temperature is 260-280° C., and the reaction pressure is 0.7-0.8 MPa.

[0029] Preferably, the mass ratio of acetic acid to n-butyric acid is 2.5-3:1.

[0030] The present invention uses acetic acid and n-butyric acid as raw materials and a catalyst composition to efficiently produce 2-pentanone; by optimizing the composition of the catalyst composition, reaction conditions and the 2-pentanone synthesis process, the conversion rate of n-butyric acid reaches 100%, and the selectivity of 2-pentanone reaches 83%, which can significantly improve the yield and selectivity of the product. The method for synthesizing 2-pentanone using the catalyst composition of the present invention has the advantages of mild reaction conditions, high selectivity, high product yield, easy continuous production, etc., and has good application prospects.

[0031] Obviously, according to the above contents of the present invention, in accordance with common technical knowledge and customary means in the art, without departing from the above basic technical ideas of the present invention, other various forms of modification, replacement or change may be made.

[0032] The above contents of the present invention are further described in detail below through specific implementation methods in the form of embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following examples. All technologies realized based on the above contents of the present invention belong to the scope of the present invention. DETAILED DESCRIPTION

[0033] In the following examples and experimental examples, reagents and raw materials not specifically described are all commercially available products.

[0034] Example 1 Method 1 for synthesizing 2-pentanone

[0035] 1. Preparation method of catalyst composition

[0036] The ZrO2-Al2O3 composite carrier was prepared by an impregnation method. The impregnation method was carried out with reference to the following literature: "Gao Xiao, Liu Xinmei, Yan Zifeng. Preparation and Application of ZrO2-Al2O3 Catalyst Carrier [J]. Industrial Catalysis, 2008, 16(3): 6.". The specific preparation process is to use 0.93 mol / L Zr(NO3)2•5H2O solution to impregnate the molded alumina carrier, dry it in a forced air drying oven at 110 °C for 10 h, and then use a muffle furnace to heat the carrier.

[0037] The composite carrier was calcined at 300 °C for 5 h to obtain a ZrO2-Al2O3 composite carrier. The composite active metal nitrate solution (4.150 M Cu(NO3)2•3H2O, 0.575 M Ce(NO3)3•6H2O, 0.100 M La(NO3)3•6H2O) was further impregnated on the composite carrier for 30 h by impregnation, stirred evenly and then allowed to stand; the impregnated composite carrier was dried at 120 °C for 12 h and calcined at 400 °C for 6 h to form a catalyst composition MO. x / ZrO2-Al2O3. Wherein M represents a metal element, and X is the total number of oxygen atoms that satisfy the valence of each element in the catalyst composition. The metal element M in the catalyst composition is a combination of Cu and a rare earth element, and the rare earth element is Ce and La. The proportion of each component in the catalyst composition is: CuO:CeO2:La2O3:ZrO2-Al2O3=20:6:4:70.

[0038] 2. Synthesis of 2-pentanone

[0039] The catalyst composition was filled into a fixed bed reactor to a thickness of 20 cm, and a mixed solution of acetic acid and n-butyric acid in a mass ratio of 2.5:1 was introduced into the fixed bed reactor by a pump. The reaction was carried out at 260°C and 0.7 MPa, and 2-pentanone was collected.

[0040] Example 2 Method 2 for synthesizing 2-pentanone

[0041] 1. Preparation method of catalyst composition

[0042] The ZrO2-Al2O3 composite carrier was prepared by an impregnation method. The "impregnation method" was carried out with reference to the following literature: "Gao Xiao, Liu Xinmei, Yan Zifeng. Preparation and Application of ZrO2-Al2O3 Catalyst Carrier [J]. Industrial Catalysis, 2008, 16(3): 6.". The specific preparation process is to use 0.93 mol / L Zr(NO3)2•5H2O solution to impregnate the molded alumina carrier, dry it at 110°C in a forced air drying oven for 10 h, and then calcine it at 300°C in a muffle furnace for 5 h to obtain the ZrO2-Al2O3 composite carrier. The composite active metal nitrate solution (2.040 M Cu(NO3)2•3H2O, 0.157 M Ce(NO3)3•6H2O, 0.021 M La(NO3)3•6H2O) was further impregnated on the composite support for 30 h by impregnation method, stirred evenly and then allowed to stand; the impregnated composite support was dried at 120 °C for 12 h and calcined at 450 °C for 6 h to form a catalyst composition MO x / ZrO2-Al2O3. Wherein M represents a metal element, and X is the total number of oxygen atoms that satisfy the valence of each element in the catalyst composition. The metal element M in the catalyst composition is a combination of Cu and a rare earth element, and the rare earth element is Ce and La. The proportion of each component in the catalyst composition is: CuO:CeO2:La2O3:ZrO2-Al2O3=12:2:1:85.

[0043] 2. Synthesis of 2-pentanone

[0044] The catalyst composition was filled into a fixed bed reactor to a thickness of 20 cm, and a mixed solution of acetic acid and n-butyric acid in a mass ratio of 2.5:1 was introduced into the fixed bed reactor by a pump. The reaction was carried out at 280°C and 0.8MPa, and 2-pentanone was collected.

[0045] This comparative example provides the control sample used in the experiment.

[0046] Comparative Example 1 Catalyst composition without doping with rare earth element La

[0047] The catalyst was prepared according to the method of Example 1, except that the rare earth element La was not doped in the catalyst composition, and the composition ratio was CuO:CeO2:ZrO2-Al2O3=20:6:74.

[0048] Comparative Example 2 Catalyst composition without doping with rare earth element Ce

[0049] The catalyst was prepared according to the method of Example 1, except that the rare earth element Ce was not doped in the catalyst composition, and the composition ratio was CuO:La2O3:ZrO2-Al2O3=20:4:76.

[0050] Comparative Example 3 Catalyst composition without doping with rare earth elements La and Ce

[0051] The catalyst was prepared according to the method of Example 1, except that the rare earth elements La and Ce were not doped in the catalyst composition, and the ratio was CuO:ZrO2-Al2O3=20:80.

[0052] Comparative Example 4: Catalyst composition with changed calcination temperature

[0053] The method of Example 1 was followed, except that the calcination temperature of the catalyst composition was 500°C.

[0054] Comparative Example 5 Catalyst composition with alumina as carrier

[0055] The catalyst was prepared according to the method of Example 1, except that the carrier of the catalyst composition was alumina.

[0056] Comparative Example 6 Method 1 for synthesizing 2-pentanone Composition

[0057] The method of Example 1 was used for preparation, except that the reaction temperature was 240°C and the pressure was 1.2 MPa.

[0058] Comparative Example 7 Method 2 for Synthesizing 2-Pentanone Composition

[0059] The method of Example 1 was followed, except that the catalyst composition was packed in a fixed bed reactor to a thickness of 10 cm.

[0060] Comparative Example 8 Method 3 for Synthesizing 2-Pentanone Composition

[0061] The method of Example 1 was used for preparation, except that the mass ratio of acetic acid to n-butyric acid was 4:1.

[0062] The technical solution of the present invention is further illustrated by experiments below.

[0063] Experimental Example 1 Screening experiment of catalyst composition used for synthesizing 2-pentanone

[0064] The samples used in this experimental example were prepared according to the methods of Example 1, Example 2, Comparative Example 1, Comparative Example 2, Comparative Example 3, Comparative Example 4, and Comparative Example 5.

[0065] 1. Experimental Methods

[0066] 1. Butyric acid conversion rate

[0067]

[0068] 2. Selectivity of 2-pentanone

[0069]

[0070] 3. Chromatographic analysis

[0071] Analytical instruments: GC7890A, FID detector, FFAP capillary column

[0072] 2. Experimental Results

[0073] The results of the conversion rate of n-butyric acid and the selectivity of 2-pentanone of Example 1, Example 2 and Comparative Examples 1-5 are shown in Table 1. It can be seen that when the catalyst composition is composed of CuO, CeO2, La2O3 and ZrO2-Al2O3, the conversion rate of n-butyric acid reaches 100% and the selectivity of 2-pentanone is 83%. It can be seen that according to the 2-pentanone synthesis method of Example 1, the conversion rate of n-butyric acid is high and the selectivity of 2-pentanone is the best.

[0074] Table 1

[0075]

[0076] Experimental Example 2 Optimization of the Preparation Method of 2-Pentanone

[0077] The samples used in this experimental example were prepared according to the methods of Example 1, Example 2, Comparative Example 6, Comparative Example 7, and Comparative Example 8.

[0078] 1. Experimental Methods

[0079] 1. Butyric acid conversion rate

[0080]

[0081] 2. Selectivity of 2-pentanone

[0082]

[0083] 3. Chromatographic analysis

[0084] Analytical instruments: GC7890A, FID detector, FFAP capillary column

[0085] 2. Experimental Results

[0086] The results of the n-butyric acid conversion rate and the selectivity of 2-pentanone in Example 1, Example 2, and Comparative Examples 6-8 are shown in Table 2. It can be seen that when the mass ratio of acetic acid to n-butyric acid is 2.5:1, the reaction temperature and pressure are 260°C, 0.7 MPa, and the catalyst loading thickness is 20 cm, the n-butyric acid conversion rate reaches 100% and the 2-pentanone selectivity is 83%. It can be seen that according to the 2-pentanone synthesis method of Example 1, the n-butyric acid conversion rate is high and the 2-pentanone selectivity is the best.

[0087] Table 2

[0088]

[0089] In summary, the present invention conducts screening experiments on the composition and reaction conditions of the catalyst composition for synthesizing 2-pentanone, and optimizes the synthesis process of 2-pentanone, so that the method for synthesizing 2-pentanone of the present invention and the catalyst composition used therein have obvious advantages, achieve a higher n-butyric acid conversion rate and 2-pentanone selectivity, can significantly improve the yield of the product, and has broad application prospects.

Claims

1. A catalyst composition, characterized in that It is made of the following materials by weight: 12-20 parts of copper oxide, 2-6 parts of cerium oxide, 1-4 parts of lanthanum oxide, 70-85 parts of zirconium oxide-aluminum oxide composite carrier.

2. The catalyst composition according to claim 1, characterized in that It is made of the following materials by weight: 20 parts of copper oxide, 6 parts of cerium oxide, 4 parts of lanthanum oxide, 70 parts of zirconium oxide-aluminum oxide composite carrier.

3. The catalyst composition according to claim 1 or 2, characterized in that Its preparation method comprises the following steps: Step 1: calcining the zirconium oxide-aluminum oxide composite carrier; Step 2: Impregnate Cu(NO3)2•3H2O solution, Ce(NO3)3•6H2O solution and La(NO3)3•6H2O solution on the calcined zirconium oxide-alumina composite carrier, dry and calcine to obtain.

4. The catalyst composition according to claim 3, characterized in that In step 1, the calcination temperature is 200-600°C and the calcination time is 2-10 h; And / or, in step 2, the impregnation time is 24-36 h; the drying temperature is 60-150° C., and the drying time is 2-24 h; the roasting temperature is 200-1000° C., and the roasting time is 2-24 h.

5. The method for preparing the catalyst composition according to claim 1 or 2, characterized in that: The following steps are involved: Step 1: calcining the zirconium oxide-aluminum oxide composite carrier; Step 2: Impregnate Cu(NO3)2•3H2O solution, Ce(NO3)3•6H2O solution and La(NO3)3•6H2O solution on the calcined zirconium oxide-alumina composite carrier, dry and calcine to obtain.

6. Use of the catalyst composition according to any one of claims 1 to 4 as a catalyst for synthesizing 2-pentanone.

7. A method for synthesizing 2-pentanone, characterized in that: The following reactions are included: Acetic acid and n-butyric acid are introduced into a reactor containing the catalyst composition according to any one of claims 1 to 4 to react and prepare 2-pentanone. The reaction formula is: .

8. The method according to claim 7, characterized in that The catalyst composition is filled in the reactor to a thickness of 10-25 cm; the reaction temperature is 220-280° C., the reaction pressure is 0.4-1.8 MPa; and the mass ratio of acetic acid to n-butyric acid is 1-4:

1.

9. The method according to claim 8, characterized in that The catalyst composition is filled in the reactor with a thickness of 20 cm; the reaction temperature is 260-280° C., and the reaction pressure is 0.7-0.8 MPa.

10. The method according to claim 8, characterized in that The mass ratio of the acetic acid to n-butyric acid is 2.5-3:1.

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