A catalyst for 1-methoxy-2-acetone synthesis process and its preparation method and application

Abstract

The present invention discloses a catalyst for the dehydrogenation synthesis of 1-methoxy-2-propanone from 1-methoxy-2-propanol, which uses Ba and Cu as the main active components of the bimetallic catalyst, uses the functional element N as an electronic modifier, and uses nano-spherical silica as the catalyst support. The Ba content is 0.1%-20% of the catalyst mass, and the Cu content is 10%-30% of the catalyst mass. The present invention also discloses its preparation method and application. The catalyst of the present invention has high catalytic activity, low dehydrogenation temperature, and high liquid mass space velocity during the dehydrogenation process. Among them, under certain mild reaction conditions (reaction temperature 180°C, normal pressure, mass space velocity of 1-methoxy-2-propanol 10 h-1), the dehydrogenation conversion rate of 1-methoxy-2-propanol can reach 90%, the selectivity of 1-methoxy-2-propanone can reach 99.9%, and the stability is ≥1000 h.

Description

Technical Field

[0001] The invention relates to the technical field of catalysts, and in particular to a catalyst used in the synthesis process of 1-methoxy-2-acetone, and a preparation method and application thereof. Background Art

[0002] 1-Methoxy-2-propanone is a very important fine chemical product, mainly used as an important raw material in the synthesis of the pesticide isopropylamine and some pharmaceutical synthetic raw materials; at the same time, 1-methoxy-2-propanone is also an organic solvent with excellent performance, widely used in paints, daily cleaning agents, dyes, textiles and other industries. At present, isopropylamine, as a low-toxic herbicide, has been widely used in dry fields in the north and has a huge market. As one of the important raw materials for the production of isopropylamine, 1-methoxy-2-propanone has a broad application market space.

[0003] 1-methoxy-2-propanone can be obtained by oxidation of 1-methoxy-2-propanol, but the hydroxyl group of 1-methoxy-2-propanol is extremely difficult to oxidize due to the inductive effect of the methoxy group and the intramolecular hydrogen bond. Among the synthesis methods reported in the literature, only the air oxidation method is widely used in industrial production. However, in an environment with sufficient oxygen, the metal catalyst is easily deactivated and the catalyst needs to be replaced regularly. At the same time, this method also has the disadvantages of poor selectivity and low yield. Patent CN101121650A uses electrolytic silver as a catalyst, passes 1-methoxy-2-propanol and oxygen through a reactor, and oxidizes 1-methoxy-2-propanone at a high temperature of 300-600°C. Although the conversion rate is as high as 98%, the selectivity of the target product 1-methoxy-2-propanone is only 70%. Wang Junwei et al. prepared CuNi / SiO by impregnation. 2 Supported catalyst, using air as oxygen source to catalyze oxidation of 1-methoxy-2-propanol to 1-methoxy-2-acetone, the conversion rate of 1-methoxy-2-propanol can reach 74.3%, and the yield of 1-methoxy-2-acetone can reach 63% (Journal of Catalysis, 2002, 23: 349-351). Zhang Qi et al. prepared mixed valence vanadium phosphorus oxygen catalyst by hydrothermal method, using H 2 O 2 The catalytic activity of the catalyst for the catalytic oxidation of 1-methoxy-2-propanol to 1-methoxy-2-propanone was investigated. Under the optimal reaction conditions, the conversion rate of 1-methoxy-2-propanol was 86.9%, and the selectivity of 1-methoxy-2-propanone was 33.2% (Liaoning Chemical Industry, 2015, 44: 1058-1061).

[0004] In the existing process technology scheme, the catalytic oxidation method is mostly used in the reaction process of preparing the product 1-methoxy-2-propanone from the raw material 1-methoxy-2-propanol. In fact, the essence of the reaction is a catalytic dehydrogenation process, and the addition of an oxygen source is essentially for dehydrogenation. However, a large amount of oxidants such as oxygen need to be added during the reaction. First of all, this will cause some raw materials and products to be deeply oxidized, thereby producing a large amount of by-products (such as propionaldehyde, acetone, water, etc.), which not only increases the difficulty of separation in subsequent processes, but also causes large losses of raw materials and high production costs; secondly, the addition of oxidants such as oxygen will also reduce the reliability of the entire process technology, that is, organic matter is prone to combustion and explosion in the presence of oxidant oxygen, which increases the potential safety hazards in the process. Patent CN107628933B reports a CuMgCaK / SiO prepared by a sol-gel method. 2 The catalyst is used to dehydrogenate 1-methoxy-2-propanol to prepare 1-methoxy-2-acetone. However, the reaction needs to be carried out at a higher temperature, and due to the poor activity of the catalyst, the experiment can only be carried out under lower space velocity conditions. Since the dehydrogenation reaction is a strongly endothermic reaction, a higher reaction temperature means excessive energy consumption, which will be detrimental to production cost control. The lower reaction space velocity will result in the need for a larger reactor and more catalysts in the subsequent industrial production scale-up process, which will significantly increase the production cost of 1-methoxy-2-acetone. Summary of the invention

[0005] Aiming at the problems of poor catalytic system activity, high reaction temperature and high production cost in the existing 1-methoxy-2-acetone synthesis process, the present invention provides a green, clean, inexpensive, simple and easy-to-obtain catalyst for the process of dehydrogenating 1-methoxy-2-propanol to synthesize 1-methoxy-2-acetone, which has high catalytic activity, large catalytic dehydrogenation reaction space velocity and low reaction temperature, as well as a preparation method and application thereof.

[0006] The technical solution adopted by the present invention is:

[0007] A catalyst for the process of synthesizing 1-methoxy-2-acetone by dehydrogenation of 1-methoxy-2-propanol, wherein the catalyst uses Ba and Cu as bimetallic main active components of the catalyst, uses functional element N as an electronic modifier, and uses nano-spherical silicon oxide as a catalyst carrier, wherein the Ba content is 0.1%-20% of the catalyst mass, and the Cu content is 10%-30% of the catalyst mass;

[0008] The catalyst is prepared by the following steps:

[0009] 1) Dissolve a certain amount of soluble salt of Ba in deionized water, wherein the concentration of Ba ions is 0.01-1.0M;

[0010] 2) Weighing a certain amount of citric acid, adding it to the solution of step 1), and stirring to form a uniform mixed solution, wherein the pH value of the mixed solution is 3-6;

[0011] 3) Weigh a certain amount of nano-spherical silica sol, add it to the mixed solution of step 2), and stir it ultrasonically at 5-120KHz and 100-300r / min at room temperature for 2-12h, then heat it to 120-180°C and microwave it at 100-200KHz for 2-12h;

[0012] 4) adding 0.01-0.1M p-aminobenzoic acid aqueous solution to the mixed solution of step 3), wherein the volume ratio of the p-aminobenzoic acid aqueous solution to the soluble salt solution of Ba in step 1) is controlled at 1 / 1-1 / 5, and ultrasonic stirring is performed at 5-120KHz and 100-300r / min at room temperature for 2-12h;

[0013] 5) dissolving a certain amount of Cu soluble salt in DMF solvent, wherein the concentration of Cu ions is 0.1-1.2 mol / L; dissolving a certain amount of trimesic acid in DMF solvent, wherein the concentration of trimesic acid is 0.1-1.2 mol / L, mixing the trimesic acid DMF solution and the Cu soluble salt DMF solution in a volume ratio of 1 / 1-2 / 1, stirring ultrasonically at 5-120 KHz and 100-300 r / min for 2-5 h at room temperature, then heating to 120-180° C., maintaining ultrasonic stirring for 2-12 h, then cooling to room temperature and filtering to obtain a solid;

[0014] 6) adding the solid obtained in step 5) to the mixed solution in step 4), stirring ultrasonically at 5-120KHz and 100-300r / min at room temperature for 2-12h, then heating to 120-180°C, microwave treatment at 100-200KHz for 2-12h, then cooling to room temperature and filtering to obtain a solid;

[0015] 7) Wash the solid obtained in step 6) with deionized water or ethanol, and then dry it at 60-120° C. for 10-24 h; and then calcine it at 350-900° C. for 3-10 h in an inert gas atmosphere to obtain the catalyst Cu-Ba-N / SiO 2 ;

[0016] 8) The catalyst prepared in step 7) needs to be reduced with hydrogen before use, with a pressure of 0.05-0.3 MPa, a reduction temperature of 150-300°C, and a hydrogen gas space velocity of 100-3000 h -1 , the reduction time is 2-10h.

[0017] Furthermore, the Ba content is 0.5%-5% of the catalyst mass, and the Cu content is 12%-25% of the catalyst mass.

[0018] Furthermore, the soluble salt of Ba is one or more of barium nitrate, barium acetate, and barium chloride, and the soluble salt of Cu is one or more of copper nitrate, copper acetate, copper formate, and copper chloride.

[0019] A method for preparing a catalyst used in the process of dehydrogenating 1-methoxy-2-propanol to synthesize 1-methoxy-2-acetone is prepared by the following steps:

[0020] 1) Dissolve a certain amount of soluble salt of Ba in deionized water, wherein the concentration of Ba ions is 0.01-1.0M;

[0021] 2) Weighing a certain amount of citric acid, adding it to the solution of step 1), and stirring to form a uniform mixed solution, wherein the pH value of the mixed solution is 3-6;

[0022] 3) Weigh a certain amount of nano-spherical silica sol, add it to the mixed solution of step 2), and stir it ultrasonically at 5-120KHz and 100-300r / min at room temperature for 2-12h, then heat it to 120-180°C and microwave it at 100-200KHz for 2-12h;

[0023] 4) adding 0.01-0.1M p-aminobenzoic acid aqueous solution to the mixed solution of step 3), wherein the volume ratio of the p-aminobenzoic acid aqueous solution to the soluble salt solution of Ba in step 1) is controlled at 1 / 1-1 / 5, and ultrasonic stirring is performed at 5-120KHz and 100-300r / min at room temperature for 2-12h;

[0024] 5) dissolving a certain amount of Cu soluble salt in DMF solvent, wherein the concentration of Cu ions is 0.1-1.2 mol / L; dissolving a certain amount of trimesic acid in DMF solvent, wherein the concentration of trimesic acid is 0.1-1.2 mol / L, mixing the trimesic acid DMF solution and the Cu soluble salt DMF solution in a volume ratio of 1 / 1-2 / 1, stirring ultrasonically at 5-120 KHz and 100-300 r / min for 2-5 h at room temperature, then heating to 120-180° C., maintaining ultrasonic stirring for 2-12 h, then cooling to room temperature and filtering to obtain a solid;

[0025] 6) adding the solid obtained in step 5) to the mixed solution in step 4), stirring ultrasonically at 5-120KHz and 100-300r / min at room temperature for 2-12h, then heating to 120-180°C, microwave treatment at 100-200KHz for 2-12h, then cooling to room temperature and filtering to obtain a solid;

[0026] 7) Wash the solid obtained in step 6) with deionized water or ethanol, and then dry it at 60-120° C. for 10-24 h; and then calcine it at 350-900° C. for 3-10 h in an inert gas atmosphere to obtain the catalyst Cu-Ba-N / SiO2 ;

[0027] 8) The catalyst prepared in step 7) needs to be reduced with hydrogen before use, with a pressure of 0.05-0.3 MPa, a reduction temperature of 150-300°C, and a hydrogen gas space velocity of 100-3000 h -1 , the reduction time is 2-10h;

[0028] The prepared catalyst uses Ba and Cu as bimetallic main active components of the catalyst, functional element N as an electronic modifier, and nano-spherical silicon oxide as a catalyst carrier, wherein the Ba content is 0.1%-20% of the catalyst mass, and the Cu content is 10%-30% of the catalyst mass.

[0029] Furthermore, the Ba content is 0.5%-5% of the catalyst mass, and the Cu content is 12%-25% of the catalyst mass.

[0030] Furthermore, the soluble salt of Ba is one or more of barium nitrate, barium acetate, and barium chloride, and the soluble salt of Cu is one or more of copper nitrate, copper acetate, copper formate, and copper chloride.

[0031] The catalyst is used in the process of dehydrogenating 1-methoxy-2-propanol to synthesize 1-methoxy-2-acetone. 1-methoxy-2-propanol is mixed with an inert gas, and then reacted in a continuous flow packed bed reactor in the presence of the catalyst at a reaction temperature of 150 to 220° C. and a reaction pressure of normal pressure to obtain the target product.

[0032] Furthermore, the reaction temperature is 180-200°C.

[0033] Furthermore, the mass space velocity of the 1-methoxy-2-propanol is 1.2-15h -1 , inert gas space velocity is 100-6000h -1 .

[0034] Furthermore, the mass space velocity of the 1-methoxy-2-propanol is 8-15h -1 .

[0035] Beneficial effects of the present invention:

[0036] The catalyst for catalyzing the dehydrogenation of 1-methoxy-2-propanol to synthesize 1-methoxy-2-acetone has high catalytic activity, low dehydrogenation temperature and high liquid mass space velocity during the dehydrogenation process. -1 ) The dehydrogenation conversion rate of 1-methoxy-2-propanol can reach 90%, the selectivity of 1-methoxy-2-acetone can reach 99.9%, and the stability is ≥1000h.

[0037] The catalyst of the present invention is prepared by a two-step method of "gel hydrothermal crystallization" and "coordinated covalent adsorption". The catalyst has an eggshell structure, and the bimetallic components Ba and Cu are in close contact and highly dispersed on the surface of the catalyst shell layer, forming a strong chemical bond with the carrier. N is incorporated to adjust the electronic properties of the bimetallic, optimize the adsorption activation and desorption of the reactant molecules and product molecules on the catalyst surface, thereby improving the catalyst activity, the selectivity and stability of the target product 1-methoxy-2-acetone. First, the hydroxyl group in citric acid is coordinated with the metal barium salt precursor to form a Ba-OC chemical bond, and a weak sol state is formed during the stirring process. Subsequently, nano-spherical silica sol is introduced into the reaction system, and the carboxyl group in the citric acid molecule is used to react with the hydroxyl group on the surface of the nano-spherical silica sol for esterification to form a silicon ester bond. Using the bridge effect of the citric acid molecule, a section of hydroxyl anchors the metal barium ion, and a section of carboxyl is fixed on the surface of the nano-spherical silica sol to form a highly dispersed barium oxide silicon precursor. Further, under ultrasonic and high-temperature microwave hydrothermal conditions, the highly dispersed barium ions on the surface of the nano-spherical silica sol crystallize with the carrier to form a Ba-O-Si chemical bond. This allows the metal ions to be stably anchored on the surface of the nano-spherical silica sol. Subsequently, p-aminobenzoic acid is introduced into the mixture, and the carboxyl group is used to bind to Ba / SiO 2 Preparation of Ba / SiO by forming ester bonds with vacant silanol groups on the surface 2 -NH 2 Precursor, so that the amino group at the other end of p-aminobenzoic acid can be bonded with the carboxyl group in trimesic acid. Similarly, the two carboxyl groups in trimesic acid are used to coordinate with Cu ions to form molecular-level coordination protection groups, and the bonding force between the carboxyl group and Cu ions is improved under ultrasonic and hydrothermal conditions. 2 -NH 2 The amino group of the precursor reacts with the third carboxyl group in trimesic acid to form an amide bond to anchor the Cu ion. Ultrasonic and high-temperature microwave hydrothermal conditions promote the amidation reaction process. Finally, under inert gas calcination conditions, a high-performance dehydrogenation catalyst with an eggshell-shaped structure, close contact and high dispersion of bimetallic materials supported on the surface of nano-spherical silicon oxide is formed. Moreover, due to the introduction of N between the bimetallic materials, the N atoms can be used to coordinate the electronic modification of the bimetallic materials so that the subsequent application of the catalyst in the dehydrogenation process can improve the catalytic performance.

[0038] Compared with the traditional catalyst preparation method, the present invention adopts "gel hydrothermal crystallization" and "coordinated covalent adsorption" to prepare the catalyst, and gradually introduces active components on the surface of nano-spherical silicon oxide, which not only allows the active components to be highly dispersed on the catalyst surface to form an eggshell structure, but also facilitates the formation of strong interaction between the bimetallics. In addition, the present invention utilizes the formation of amide bonds to insert functional N elements between the bimetallics, so as to adjust the electronic interaction between the bimetallics, promote the adsorption activation of reactants and the desorption of products, and improve the catalytic performance of dehydrogenating 1-methoxy-2-propanol to prepare 1-methoxy-2-acetone.

[0039] The bimetallic eggshell-shaped supported catalyst prepared by the novel method adopted in the present invention exhibits excellent catalytic performance in the process of dehydrogenation of 1-methoxy-2-propanol to 1-methoxy-2-acetone. Even under low temperature and high space velocity conditions, it can still exhibit excellent catalytic performance. At a reaction temperature of 180°C, normal pressure, and a mass space velocity of 10h-1, the reaction temperature of 1-methoxy-2-propanol was 100 °C. -1 Under the reaction conditions, the dehydrogenation conversion rate of 1-methoxy-2-propanol can reach 90%, the selectivity of 1-methoxy-2-acetone can reach 99.9%, and the stability is ≥1000h. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is an electron microscope image of the catalyst of Example 1.

[0041] Figure 2 This is a gas chromatographic analysis chart of the product of Example 1.

[0042] Figure 3 This is a stability test data chart of the catalyst in Example 5. DETAILED DESCRIPTION

[0043] The present invention is further explained below in conjunction with the examples and drawings. The following examples are only used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0044] Example 1

[0045] Dissolve barium nitrate in deionized water to form an aqueous solution with a Ba ion concentration of 0.1M, take 20ml of the above barium nitrate aqueous solution, add citric acid, and stir to form a uniform mixed solution, wherein the pH value of the mixed solution is 4; take 50ml of 30% nano-spherical silica sol (Qingdao Ocean Chemical Co., Ltd., J30) and add it to the mixed solution, ultrasonically stir at 60KHz and 200r / min at room temperature for 3h, then heat to 180℃ and microwave at 100KHz for 10h; take 5ml of 0.05M p-aminobenzoic acid aqueous solution and add it to the mixed solution, ultrasonically stir at 60KHz and 200r / min at room temperature for 5h to obtain a precursor a mixed solution;

[0046] 50mmol Cu(NO 3 ) 2 ·3H 2 O was dissolved in 250 mL DMF, 50 mmol of trimesic acid was dissolved in 250 mL DMF, and Cu(NO 3 ) 2 ·3H 2 The O DMF solution and the trimesic acid DMF solution were mixed, and ultrasonically stirred at 60KHz and 200r / min for 3h at room temperature, then heated to 180°C and kept ultrasonically stirred for 10h, then cooled to room temperature and filtered to obtain a solid; then the obtained solid was added to the precursor a mixed solution, ultrasonically stirred at 60KHz and 200r / min for 5h at room temperature, then heated to 180°C, microwave treated at 100KHz for 10h, cooled to room temperature and filtered to obtain a solid; the obtained solid was washed with deionized water or ethanol, then dried at 100°C for 10h, and then calcined at 500°C in an inert gas atmosphere (nitrogen) for 4h to obtain the catalyst 1-Cu-Ba-N / SiO 2 The TEM image of the catalyst prepared in this example is as follows: Figure 1 shown.

[0047] The obtained catalyst was crushed into 40-60 mesh and loaded into a continuous flow packed bed reactor. High-purity hydrogen was introduced at a system pressure of 0.1 MPa (normal pressure) and a temperature of 300°C. The hydrogen gas space velocity was 2500 h -1 , reduction for 2h. The system pressure was maintained at 0.1MPa, the temperature was reduced to 180℃, the system gas was switched to nitrogen, and the nitrogen gas space velocity was 1500h -1 , 1-methoxy-2-propanol is pumped into the advection pump, and the mass space velocity of 1-methoxy-2-propanol is 10.0h -1 The liquid phase in the reaction product was sampled through the condenser for gas chromatography analysis. The gas chromatography analysis of the product in this embodiment is shown in FIG. Figure 2 As shown, the conversion rate of 1-methoxy-2-propanol is 90%, and the selectivity of the target product 1-methoxy-2-propanone is 99.9%.

[0048] Example 2

[0049] Dissolve barium nitrate in deionized water to form an aqueous solution with a Ba ion concentration of 0.1M, take 20ml of the above barium nitrate aqueous solution, add citric acid, and stir to form a uniform mixed solution, wherein the pH value of the mixed solution is 4; take 50ml of 30% nano-spherical silica sol (Qingdao Ocean Chemical Co., Ltd., J30) and add it to the mixed solution, ultrasonically stir at 60KHz and 200r / min at room temperature for 3h, then heat to 180℃ and microwave at 100KHz for 10h; take 5ml of 0.05M p-aminobenzoic acid aqueous solution and add it to the mixed solution, ultrasonically stir at 60KHz and 200r / min at room temperature for 5h to obtain a precursor a mixed solution;

[0050] 60mmol Cu(NO 3 ) 2 ·3H 2 O was dissolved in 250 mL DMF, 60 mmol trimesic acid was dissolved in 250 mL DMF, and Cu(NO 3 ) 2 ·3H 2 The O DMF solution and the trimesic acid DMF solution were mixed, and ultrasonically stirred at 60KHz and 200r / min for 3h at room temperature, then heated to 180°C and kept ultrasonically stirred for 10h, then cooled to room temperature and filtered to obtain a solid; then the obtained solid was added to the precursor a mixed solution, ultrasonically stirred at 60KHz and 200r / min for 5h at room temperature, then heated to 180°C, microwave treated at 100KHz for 10h, cooled to room temperature and filtered to obtain a solid; the obtained solid was washed with deionized water or ethanol, then dried at 100°C for 10h, and then calcined at 500°C in an inert gas atmosphere (nitrogen) for 4h to obtain the catalyst 2-Cu-Ba-N / SiO 2 .

[0051] The obtained catalyst was crushed into 40-60 mesh and loaded into a continuous flow packed bed reactor. High-purity hydrogen was introduced at a system pressure of 0.1 MPa and a temperature of 300°C. The hydrogen gas space velocity was 2500 h -1 , reduction for 2h. The system pressure was maintained at 0.1MPa, the temperature was reduced to 190℃, the system gas was switched to nitrogen, and the nitrogen gas space velocity was 1500h -1 , 1-methoxy-2-propanol is pumped into the advection pump, and the mass space velocity of 1-methoxy-2-propanol is 12.0h -1 The liquid phase in the reaction product was sampled through a condenser for gas chromatography analysis, and the conversion rate of 1-methoxy-2-propanol was 88%, and the selectivity of the target product 1-methoxy-2-propanone was 99.7%.

[0052] Example 3

[0053] Dissolve barium nitrate in deionized water to form an aqueous solution with a Ba ion concentration of 0.05M, take 20ml of the above barium nitrate aqueous solution, add citric acid, and stir to form a uniform mixed solution, wherein the pH value of the mixed solution is 4; take 50ml of 30% mass concentration of nano-spherical silica sol (Qingdao Ocean Chemical Co., Ltd., J30) and add it to the mixed solution, ultrasonically stir at 60KHz and 200r / min at room temperature for 3h, then heat to 180℃ and microwave at 100KHz for 10h; take 5ml of 0.05M p-aminobenzoic acid aqueous solution and add it to the mixed solution, ultrasonically stir at 60KHz and 200r / min at room temperature for 5h to obtain a precursor a mixed solution;

[0054] 50mmol Cu(NO 3 ) 2 ·3H 2 O was dissolved in 250 mL DMF, 50 mmol of trimesic acid was dissolved in 250 mL DMF, and Cu(NO 3 ) 2 ·3H 2 The DMF solution of O and the DMF solution of trimesic acid are mixed, and ultrasonically stirred at 60KHz and 200r / min for 3h at room temperature, and then heated to 180°C and kept ultrasonically stirred for 10h, and then cooled to room temperature and filtered to obtain a solid; then the obtained solid is added to the precursor a mixed solution, and ultrasonically stirred at 60KHz and 200r / min for 5h at room temperature, and then heated to 180°C and microwave treated at 100KHz for 10h; cooled to room temperature and filtered to obtain a solid; the obtained solid is washed with deionized water or ethanol, and then dried at 100°C for 10h; and then calcined at 500°C in an inert gas atmosphere (nitrogen) for 4h to obtain the catalyst 3-Cu-Ba-N / SiO 2 .

[0055] The obtained catalyst was crushed into 40-60 mesh and loaded into a continuous flow packed bed reactor. High-purity hydrogen was introduced at a system pressure of 0.1 MPa and a temperature of 300°C. The hydrogen gas space velocity was 2500 h -1 , reduction for 2h. The system pressure was maintained at 0.1MPa, the temperature was reduced to 180℃, the system gas was switched to nitrogen, and the nitrogen gas space velocity was 1500h -1 , 1-methoxy-2-propanol is pumped into the advection pump, and the mass space velocity of 1-methoxy-2-propanol is 10.0h -1 The liquid phase in the reaction product was sampled through a condenser for gas chromatography analysis, and the conversion rate of 1-methoxy-2-propanol was 86%, and the selectivity of the target product 1-methoxy-2-propanone was 99.8%.

[0056] Example 4

[0057] Dissolve barium nitrate in deionized water to form an aqueous solution with a Ba ion concentration of 0.1M, take 20ml of the above barium nitrate aqueous solution, add citric acid, and stir to form a uniform mixed solution, wherein the pH value of the mixed solution is 4; take 50ml of 30% mass concentration of nano-spherical silica sol (Qingdao Ocean Chemical Co., Ltd., J30) and add it to the mixed solution, ultrasonically stir at 60KHz and 200r / min at room temperature for 3h, then heat to 180℃ and microwave at 100KHz for 10h; take 5ml of 0.02M p-aminobenzoic acid aqueous solution and add it to the mixed solution, ultrasonically stir at 60KHz and 200r / min at room temperature for 5h to obtain a precursor a mixed solution;

[0058] 50mmol Cu(NO 3 ) 2 ·3H 2 O was dissolved in 250 mL DMF, 50 mmol of trimesic acid was dissolved in 250 mL DMF, and Cu(NO 3 ) 2 ·3H 2 The O DMF solution and the trimesic acid DMF solution were mixed, and ultrasonically stirred at 60KHz and 200r / min for 3h at room temperature, then heated to 180°C and kept ultrasonically stirred for 10h, then cooled to room temperature and filtered to obtain a solid; then the obtained solid was added to the precursor a mixed solution, ultrasonically stirred at 60KHz and 200r / min for 5h at room temperature, then heated to 180°C, microwave treated at 100KHz for 10h, cooled to room temperature and filtered to obtain a solid; the obtained solid was washed with deionized water or ethanol, then dried at 100°C for 10h, and then calcined at 500°C in an inert gas atmosphere (nitrogen) for 4h to obtain the catalyst 4-Cu-Ba-N / SiO 2 .

[0059] The obtained catalyst was crushed into 40-60 mesh and loaded into a continuous flow packed bed reactor. High-purity hydrogen was introduced at a system pressure of 0.1 MPa and a temperature of 300°C. The hydrogen gas space velocity was 2500 h -1 , reduction for 2h. The system pressure was maintained at 0.1MPa, the temperature was reduced to 180℃, the system gas was switched to nitrogen, and the nitrogen gas space velocity was 1500h -1 , 1-methoxy-2-propanol is pumped into the advection pump, and the mass space velocity of 1-methoxy-2-propanol is 10.0h -1 The liquid phase in the reaction product was sampled through a condenser for gas chromatography analysis, and the conversion rate of 1-methoxy-2-propanol was 85%, and the selectivity of the target product 1-methoxy-2-propanone was 99.9%.

[0060] Example 5

[0061] The stability test was carried out under the catalyst and reaction conditions described in Example 1. The reaction time was >1000 h. Samples were taken at regular intervals and analyzed by gas chromatography. Figure 3 As shown in the figure, it can be seen that the catalyst prepared by the present invention not only has high activity and high selectivity, but also has excellent stability, which is very important for further industrial scale-up application.

[0062] Comparative Example 1

[0063] Dissolve barium nitrate in deionized water to form an aqueous solution with a Ba ion concentration of 0.1M, take 20 ml of the above barium nitrate aqueous solution, add citric acid, and stir to form a uniform mixed solution, wherein the pH value of the mixed solution is 4; take 50 ml of 30% mass concentration of nano-spherical silica sol (Qingdao Ocean Chemical Co., Ltd., J30) and add it to the mixed solution, ultrasonically stir at 60KHz and 200r / min at room temperature for 3h, then heat to 180°C and microwave at 100KHz for 10h to obtain a precursor a mixed solution;

[0064] 50mmol Cu(NO 3 ) 2 ·3H 2 O was dissolved in 250 mL DMF, 50 mmol of trimesic acid was dissolved in 250 mL DMF, and Cu(NO 3 ) 2 ·3H 2 The O DMF solution and the trimesic acid DMF solution were mixed, and ultrasonically stirred at 60KHz and 200r / min for 3h at room temperature, then heated to 180°C and kept ultrasonically stirred for 10h, then cooled to room temperature and filtered to obtain a solid; then the obtained solid was added to the precursor a mixed solution, ultrasonically stirred at 60KHz and 200r / min for 5h at room temperature, then heated to 180°C, microwave treated at 100KHz for 10h, cooled to room temperature and filtered to obtain a solid; the obtained solid was washed with deionized water or ethanol, then dried at 100°C for 10h, and then calcined at 500°C in an inert gas atmosphere (nitrogen) for 4h to obtain the catalyst R1-Cu-Ba / SiO 2 .

[0065] The obtained catalyst was crushed into 40-60 mesh and loaded into a continuous flow packed bed reactor. High-purity hydrogen was introduced at a system pressure of 0.1 MPa and a temperature of 300°C. The hydrogen gas space velocity was 2500 h -1 , reduction for 2h. The system pressure was maintained at 0.1MPa, the temperature was reduced to 180℃, the system gas was switched to nitrogen, and the nitrogen gas space velocity was 1500h -1 , 1-methoxy-2-propanol is pumped into the advection pump, and the mass space velocity of 1-methoxy-2-propanol is 10.0h -1The liquid phase in the reaction product was sampled through a condenser for gas chromatography analysis, and the conversion rate of 1-methoxy-2-propanol was 30%, and the selectivity of the target product 1-methoxy-2-propanone was 90.8%.

[0066] Comparative Example 2

[0067] Dissolve barium nitrate in deionized water to form an aqueous solution with a Ba ion concentration of 0.1 M. Take 20 ml of the above barium nitrate aqueous solution and add 50 mmol Cu(NO 3 ) 2 ·3H 2 O, stirred into a uniform mixture; 50 ml of 30% nano-spherical silica sol (J30, Qingdao Ocean Chemical Co., Ltd.) was added to the mixture, and ultrasonically stirred at 60KHz and 200r / min for 3 hours at room temperature; 0.1M sodium carbonate solution was added dropwise with a horizontal flow pump until complete precipitation, aged at room temperature for 6 hours, and filtered to obtain a solid; the obtained solid was washed with deionized water, then dried at 120°C for 3 hours, and then calcined at 400°C for 4 hours to obtain the catalyst R2-Cu-Ba / SiO 2 .

[0068] The obtained catalyst was crushed into 40-60 mesh and loaded into a continuous flow packed bed reactor. High-purity hydrogen was introduced at a system pressure of 0.1 MPa and a temperature of 300°C. The hydrogen gas space velocity was 2500 h -1 , reduction for 2h. The system pressure was maintained at 0.1MPa, the temperature was reduced to 180℃, the system gas was switched to nitrogen, and the nitrogen gas space velocity was 1500h -1 , 1-methoxy-2-propanol is pumped into the advection pump, and the mass space velocity of 1-methoxy-2-propanol is 10.0h -1 The liquid phase in the reaction product was sampled through a condenser for gas chromatography analysis, and the conversion rate of 1-methoxy-2-propanol was 23%, and the selectivity of the target product 1-methoxy-2-propanone was 88.6%.

Claims

1. A catalyst for use in the process of dehydrogenating 1-methoxy-2-propanol to synthesize 1-methoxy-2-acetone, It is characterized in that The catalyst uses Ba and Cu as the bimetallic main active components of the catalyst, uses the functional element N as an electronic modifier, and uses nano-spherical silicon oxide as a catalyst carrier, wherein the Ba content is 0.1%-20% of the catalyst mass, and the Cu content is 10%-30% of the catalyst mass; The catalyst is prepared by the following steps: 1) Dissolve a certain amount of soluble salt of Ba in deionized water, wherein the concentration of Ba ions is 0.01-1.0M; 2) Weighing a certain amount of citric acid, adding it to the solution of step 1), and stirring to form a uniform mixed solution, wherein the pH value of the mixed solution is 3-6; 3) Weigh a certain amount of nano-spherical silica sol, add it to the mixed solution of step 2), and stir it ultrasonically at 5-120kHz and 100-300r / min at room temperature for 2-12h, then heat it to 120-180°C and microwave it at 100-200kHz for 2-12h; 4) adding 0.01-0.1M p-aminobenzoic acid aqueous solution to the mixed solution of step 3), wherein the volume ratio of the p-aminobenzoic acid aqueous solution to the soluble salt solution of Ba in step 1) is controlled at 1 / 1-1 / 5, and ultrasonic stirring is performed at 5-120kHz and 100-300r / min at room temperature for 2-12h; 5) dissolving a certain amount of Cu soluble salt in DMF solvent, wherein the concentration of Cu ions is 0.1-1.2 mol / L; dissolving a certain amount of trimesic acid in DMF solvent, wherein the concentration of trimesic acid is 0.1-1.2 mol / L, mixing the trimesic acid DMF solution and the Cu soluble salt DMF solution in a volume ratio of 1 / 1-2 / 1, stirring ultrasonically at 5-120 kHz and 100-300 r / min for 2-5 h at room temperature, then heating to 120-180° C., maintaining ultrasonic stirring for 2-12 h, then cooling to room temperature and filtering to obtain a solid; 6) adding the solid obtained in step 5) to the mixed solution in step 4), stirring ultrasonically at 5-120 kHz and 100-300 r / min for 2-12 h at room temperature, then heating to 120-180° C., treating with microwaves at 100-200 kHz for 2-12 h, then cooling to room temperature and filtering to obtain a solid; 7) Wash the solid obtained in step 6) with deionized water or ethanol, and then dry it at 60-120° C. for 10-24 h; and then calcine it at 350-900° C. for 3-10 h in an inert gas atmosphere to obtain the catalyst Cu-Ba-N / SiO 2 ; 8) The catalyst prepared in step 7) needs to be reduced with hydrogen before use, with a pressure of 0.05-0.3 MPa, a reduction temperature of 150-300°C, and a hydrogen gas space velocity of 100-3000 h -1 , the reduction time is 2-10h.

2. A catalyst for the dehydrogenation of 1-methoxy-2-propanol to synthesize 1-methoxy-2-acetone according to claim 1, It is characterized in that The Ba content is 0.5%-5% of the catalyst mass, and the Cu content is 12%-25% of the catalyst mass.

3. A catalyst for the process of synthesizing 1-methoxy-2-acetone by dehydrogenation of 1-methoxy-2-propanol according to claim 1, It is characterized in that The soluble salt of Ba is one or more of barium nitrate, barium acetate and barium chloride, and the soluble salt of Cu is one or more of copper nitrate, copper acetate, copper formate and copper chloride.

4. A method for preparing a catalyst for dehydrogenation of 1-methoxy-2-propanol to synthesize 1-methoxy-2-acetone, It is characterized in that The preparation was carried out using the following steps: 1) Dissolve a certain amount of soluble salt of Ba in deionized water, wherein the concentration of Ba ions is 0.01-1.0M; 2) Weighing a certain amount of citric acid, adding it to the solution of step 1), and stirring to form a uniform mixed solution, wherein the pH value of the mixed solution is 3-6; 3) Weigh a certain amount of nano-spherical silica sol, add it to the mixed solution of step 2), and stir it ultrasonically at 5-120kHz and 100-300r / min at room temperature for 2-12h, then heat it to 120-180°C and microwave it at 100-200kHz for 2-12h; 4) adding 0.01-0.1M p-aminobenzoic acid aqueous solution to the mixed solution of step 3), wherein the volume ratio of the p-aminobenzoic acid aqueous solution to the soluble salt solution of Ba in step 1) is controlled at 1 / 1-1 / 5, and ultrasonic stirring is performed at 5-120kHz and 100-300r / min at room temperature for 2-12h; 5) dissolving a certain amount of Cu soluble salt in DMF solvent, wherein the concentration of Cu ions is 0.1-1.2 mol / L; dissolving a certain amount of trimesic acid in DMF solvent, wherein the concentration of trimesic acid is 0.1-1.2 mol / L, mixing the trimesic acid DMF solution and the Cu soluble salt DMF solution in a volume ratio of 1 / 1-2 / 1, stirring ultrasonically at 5-120 kHz and 100-300 r / min for 2-5 h at room temperature, then heating to 120-180° C., maintaining ultrasonic stirring for 2-12 h, then cooling to room temperature and filtering to obtain a solid; 6) adding the solid obtained in step 5) to the mixed solution in step 4), stirring ultrasonically at 5-120 kHz and 100-300 r / min for 2-12 h at room temperature, then heating to 120-180° C., treating with microwaves at 100-200 kHz for 2-12 h, then cooling to room temperature and filtering to obtain a solid; 7) Wash the solid obtained in step 6) with deionized water or ethanol, and then dry it at 60-120° C. for 10-24 h; and then calcine it at 350-900° C. for 3-10 h in an inert gas atmosphere to obtain the catalyst Cu-Ba-N / SiO 2 ; 8) The catalyst prepared in step 7) needs to be reduced with hydrogen before use, with a pressure of 0.05-0.3 MPa, a reduction temperature of 150-300°C, and a hydrogen gas space velocity of 100-3000 h -1 , the reduction time is 2-10h; The prepared catalyst uses Ba and Cu as bimetallic main active components of the catalyst, functional element N as an electronic modifier, and nano-spherical silicon oxide as a catalyst carrier, wherein the Ba content is 0.1%-20% of the catalyst mass, and the Cu content is 10%-30% of the catalyst mass.

5. A method for preparing a catalyst for dehydrogenation of 1-methoxy-2-propanol to synthesize 1-methoxy-2-acetone according to claim 4, It is characterized in that The Ba content is 0.5%-5% of the catalyst mass, and the Cu content is 12%-25% of the catalyst mass.

6. A method for preparing a catalyst for dehydrogenation of 1-methoxy-2-propanol to 1-methoxy-2-acetone according to claim 4, It is characterized in that The soluble salt of Ba is one or more of barium nitrate, barium acetate and barium chloride, and the soluble salt of Cu is one or more of copper nitrate, copper acetate, copper formate and copper chloride.

7. Use of the catalyst according to any one of claims 1 to 3 in the process of dehydrogenating 1-methoxy-2-propanol to synthesize 1-methoxy-2-acetone, It is characterized in that 1-Methoxy-2-propanol is mixed with an inert gas, and then reacted in a continuous flow packed bed reactor in the presence of a catalyst at a reaction temperature of 150-220° C. and a reaction pressure of normal pressure to obtain a target product.

8. The use according to claim 7, It is characterized in that The reaction temperature is 180-200°C.

9. The use according to claim 7, It is characterized in that The mass space velocity of the 1-methoxy-2-propanol is 1.2-15h -1 , inert gas space velocity is 100-6000h -1 .

10. The use according to claim 9, It is characterized in that The mass space velocity of the 1-methoxy-2-propanol is 8-15h -1 .

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