CN108299358A - For furan alcohol or the process for selective oxidation of aldehyde compound - Google Patents

Abstract

The present invention relates to the selective oxidation method of furan alcohol or aldehyde compounds, comprising making the raw material compound oxidize with air or pure oxygen in a solvent in the presence of a catalyst, wherein the solvent is water, an organic solvent or a mixture thereof, the The catalyst is a supported metal catalyst in which the active component is supported on a carrier having the general formula _Ma ( _XOb ) _c (Z) _d , wherein M, X, Z and a, b, c and d are as defined herein, and The active component is one or more transition metals selected from Group VIIIB and Group IB of the Periodic Table of Elements. Through the method of the present invention, furan aldehyde or acid can be prepared with high conversion (up to 100%) and high selectivity (up to 100%), and the process of the present invention is simple, the reaction equipment is simple, easy to operate, and does not require additional Alkali is added, the reaction conditions are mild, the catalyst is cheap and easy to obtain, the product, the catalyst and the solvent system are easy to separate, the reaction cycle is short, it is suitable for industrial production, and has very broad application prospects.

Description

Selective oxidation method for furan alcohol or aldehyde compound

technical field

The invention relates to a high-efficiency selective oxidation method for furan alcohol or aldehyde compounds.

Background technique

The continuous rise of oil prices and the increasing scarcity of oil resources have seriously threatened the chemical industry based on oil and affected the development of the national economy. Starting from renewable biomass sources, through efficient biological and chemical transformation, obtaining organic chemical intermediates with important application prospects, and seeking a reasonable and effective way for the utilization of biomass resources and the substitution of petrochemical products is the solution to this problem. effective measures for the problem. Furanaldehyde or acid compounds (such as 2,5-furandicarbaldehyde, 2,5-furandicarboxylic acid, furoic acid, etc.) are a class of important new chemical products with broad market application prospects. Furanaldehyde or acid compounds can be used as starting materials for the production of biodegradable polyester plastics, anti-corrosion and fire-resistant materials, energy chemicals, pharmaceutical intermediates, etc. According to its important application value and prospect, in 2004, the U.S. Department of Energy proposed to list 2,5-furandicarbaldehyde (DFF), 2,5-furandicarboxylic acid (FDCA) and furoic acid as important bio-based platform chemicals. Among them, 2,5-furandicarboxylic acid is similar to the structure and chemical properties of terephthalic acid, the oxidation product of p-xylene from petroleum, and can replace terephthalic acid to produce more easily degradable polyester plastic materials. So as to replace petroleum resources, realize the full utilization of biomass resources, and reduce the consumption of fossil resources. Therefore, the development of a furan aldehyde or acid synthesis process with industrialization prospects and environmentally friendly production will be one of the most urgent key issues to be solved in the biomass-based material industry.

The typical representative reaction of catalytic oxidation of furan alcohol or aldehyde compound to furan aldehyde or acid is the conversion of 5-hydroxymethylfurfural (HMF) to generate 2,5-furandicarbaldehyde or 2,5-furandicarboxylic acid. The chemical equation is as follows:

At present, in the reaction process of catalytic oxidation of 5-hydroxymethylfurfural, the generated 2,5-furandicarboxylic acid will reduce or even deactivate the catalytic activity of the noble metal catalyst, so basic compounds (such as sodium hydroxide, potassium hydroxide etc.) form salt with FDCA, thereby protects catalyst, prevents FDCA from taking place ring-opening degradation reaction simultaneously, has improved product selectivity. In 2009, Corma et al. reported that the yield of FDCA obtained by Au/CeO ₂ and Au/TiO ₂ catalysts was 99% under the conditions of 65-130 °C, 1 MPa air pressure and strong alkali (NaOH/HMF=4:1). In 2011, the Davis research group compared the catalytic activity of Pt, Pd and Au-based catalysts for the catalytic oxidation of HMF to prepare FDCA. The main product is FDCA, while the main product of Au/C and Au/TiO ₂ catalysts is 6-hydroxymethyl-2-furanoic acid, indicating that Pt and Pd are more conducive to the formation of FDCA than Au under low-temperature alkaline conditions. In 2013, Augusto’s research group used furfural as raw material, used Au/TiO ₂ catalyst and catalyzed the oxidation of furfural to furoic acid under the catalysis of external alkali NaOH. This process also requires a large amount of external alkali promoter to realize the reaction. In the above reports, the product exists in the form of formate after adding alkali in the oxidation process of HMF or furfural. Therefore, it is necessary to add a certain amount of acid in the post-treatment process of the product for acidification and then separate the product to obtain 2,5-furan. Diformic acid or furoic acid, the whole process is more cumbersome.

In 2012, Ma Hong et al reported the catalytic oxidation of HMF to FDCA under the action of a noble metal catalyst supported on an alkaline carrier, using oxygen or air as an oxidant. The catalyst active component used is Au, Ag, Pd, Pt, Ru metal or a composite component composed of two or more metals; the catalyst carrier is MgO, Mg(OH) ₂ , MgO-Al ₂ O ₃ or Mg ₆ Al(CO ₃ )(OH) ₁₆ 4H ₂ O basic material, or MgO, Mg(OH) ₂ , MgO-Al ₂ O ₃ or Mg ₆ Al(CO ₃ )(OH) ₁₆ with nanostructure • 4H ₂ O basic material. Gupta et al. used alkaline hydrotalcite (HT)-supported Au catalysts in the aqueous phase to catalyze the oxidation of HMF to obtain FDCA in higher yields. However, the stability of the catalyst in the aqueous phase is poor, and its reproducible and recyclable performance is greatly limited.

There are also few reports on the selective oxidation of HMF to DFF. In 1993, when Verdeguer et al. used Pt/C to catalyze the oxidation of HMF with molecular oxygen, they found that the product distribution depended on factors such as solvent, pH of the system, temperature, _O2 partial pressure and the characteristics of the catalyst itself. Under high temperature and neutral conditions, the yield of DFF is 19%. In 2003, Nie et al. studied the use of activated carbon-supported ruthenium (Ru/C) to catalyze the selective oxidation of HMF to generate DFF, and obtained a DFF yield of 96%. However, the reaction system used a highly toxic toluene solvent, while The use of highly toxic organic solvents has greater harm to the human body and greater pollution to the environment, which does not meet the requirements of green and sustainable development.

Contents of the invention

The purpose of the present invention is to overcome the above-mentioned defects in the prior art, and provide a new method for efficiently catalytically oxidizing furan alcohol or aldehyde compounds into furan aldehyde or acid products with high selectivity and high yield.

For this reason, the invention provides a kind of method that is used for the selective oxidation of furyl alcohol or aldehyde compound to furan aldehyde or furan acid product, described method comprises making furyl alcohol or aldehyde compound in solvent in the presence of catalyst Oxidation reaction with air or pure oxygen to obtain the desired product, wherein the solvent is selected from water, an organic solvent or a mixed solvent of water and an organic solvent, and the organic solvent is selected from alkanes, halogenated alkanes, One or more of aromatic hydrocarbons, esters, ethers, sulfones and amide solvents; the catalyst is that the active component is loaded on a carrier with the general formula _Ma (XO _b ) _c (Z) _d Supported metal catalyst, wherein M is one or more selected from Ca, Mg, Ce, Na and K; X is one or more selected from Si, P, S, V and As; Z is One or more selected from the counter group OH, CO ₃ , HCO ₃ , F and Cl; a, b, c and d are each independently selected from 1 to is an integer of 10, and the active component is one or more transition metals selected from Group VIIIB and Group IB of the Periodic Table of Elements.

In a preferred embodiment, the furyl alcohol or aldehyde compound is one or more selected from the following groups: furfuryl alcohol, furfural, C _1-6 alkyl substituted furfuryl alcohol, C _1-6 alkane substituted furfural, 5-hydroxymethylfurfural, 4-hydroxymethylfurfural, 2,5-furandimethanol and 2,5-furandicarbaldehyde.

In a preferred embodiment, the active component is one or more selected from Ru, Pd, Ir, Pt, Co, Cu and Ni.

In a preferred embodiment, based on the total mass of the catalyst, the loading amount of the active component is 0.1-30%.

In a preferred embodiment, the organic solvent is selected from n-hexane, octane, 1,4-dioxane, tetrahydrofuran, dichloromethane, ethyl acetate, dimethylsulfoxide (DMSO), N,N - one or more of dimethylformamide (DMF), gamma-butyrolactone (GBL) and gamma-valerolactone (GVL).

In a preferred embodiment, the temperature of the oxidation reaction is 0-250°C.

In a preferred embodiment, the pressure of the air or pure oxygen is 0.1-4 MPa.

In a preferred embodiment, the time for the oxidation reaction is 1-24 hours.

In a preferred embodiment, the temperature of the oxidation reaction is 0 to lower than 60° C. and the pressure of the air or pure oxygen is 0.1 to 0.5 MPa, so that the furan alcohol or aldehyde compound is selectively oxidized to The furan aldehyde products do not produce furan acid products at the same time.

In a preferred embodiment, the temperature of the oxidation reaction is 80-250° C. and the pressure of the air or pure oxygen is 1.0-4 MPa, so that the furan alcohol or aldehyde compound is selectively and completely oxidized to furanic acid Class products.

The present invention prepares the supported metal catalyst on the hydroxyapatite carrier with the general formula M _a (XO _b ) _c (Z) _d by utilizing the impregnation method to prepare the metal, under relatively mild conditions (such as ambient temperature and Catalyzing raw material furan alcohol or aldehyde compound under air atmosphere), can prepare furan aldehyde or acid product with high conversion rate (up to 100%) and high selectivity (up to 100%). Moreover, the method of the present invention can selectively produce pure aldehyde products or acid products by controlling the reaction temperature and the reaction pressure of air or oxygen. The method of the present invention not only does not need to add alkali or carry out in alkaline reaction system, and can efficiently catalyze and oxidize furan alcohol or aldehyde compound into furan aldehyde or acid product with high selectivity and high yield, the whole operation process Simple, mild conditions, environmental protection, and very good catalyst stability.

Description of drawings

Figure 1 shows a calcium hydroxyphosphate (Ca ₅ (PO ₄ ) ₃ (OH), HAP) support used in accordance with the present invention and a catalyst prepared by impregnating palladium (Pd) and ruthenium (Ru) thereon X-ray diffraction (XRD) spectra of Pd-HAP(a) and Ru-HAP(b) catalysts.

Fig. 2 shows the high-resolution dark-field scanning electron microscope of catalysts Pd-HAP (a) and Ru-HAP (b) prepared on it by impregnation method palladium (Pd) and ruthenium (Ru) on it (HAADF-STEM) image.

Fig. 3 shows the liquid phase chromatogram of the product obtained according to one embodiment of the present invention, and it is fixed wavelength (264nm) chromatogram, and wherein retention time t=26.46min, indication oxidation product is 2,5-furandicarboxylic acid, a.u. means arbitrary unit.

Detailed ways

The invention provides a method for selectively oxidizing furyl alcohol or aldehyde compound into furan aldehyde or furan acid product, the method comprises making furyl alcohol or aldehyde compound in the presence of catalyst in solvent with air Or pure oxygen oxidation reaction, to obtain the desired product.

In the method of the present invention, the solvent used is selected from water, an organic solvent or a mixed solvent composed of water and an organic solvent, and the organic solvent is selected from alkanes, halogenated alkanes, aromatics, esters, ethers, sulfones One or more of class and amide solvent; Preferably, the organic solvent is selected from n-hexane, octane, 1,4-dioxane, tetrahydrofuran, dichloromethane, ethyl acetate, dimethyl One or more of sulfoxide (DMSO), N,N-dimethylformamide (DMF), γ-butyrolactone (GBL) and γ-valerolactone (GVL).

In the method of the present invention, the catalyst used is a supported metal catalyst in which the active component is supported on a carrier having the general formula _Ma ( _XOb )c(Z) _d , for example, the active component is loaded onto on the carrier. In the general formula _Ma ( _XOb )c(Z) _d , M is one or more selected from Ca, Mg, Ce, Na and K; X is selected from Si, P, S, V One or more of and As; Z is one or more selected from the counter group OH, CO ₃ , HCO ₃ , F and Cl; a, b, c and d maintain the general formula Integers independently selected from 1 to 10 under the condition of charge balance.

In the catalyst used in the method of the present invention, the active component can be one or more transition metals selected from Group VIIIB and Group 1B of the Periodic Table of Elements; preferably, the active component is selected from Ru , one or more of Pd, Ir, Pt, Co, Cu and Ni. More preferably, based on the total mass of the catalyst, the loading of the active component is 0.1-30%.

Without being limited by any theory, the catalyst used in the present invention has the main reason of higher catalytic activity in the reaction process of catalyzing furyl alcohol or aldehyde compound to furyl aldehyde or acid may be due to the relatively mild conditions at reaction temperature (such as Under ambient temperature and air or oxygen atmosphere), the raw materials are not easy to polymerize or aggregate, and the carrier hydroxyapatite (HAP) itself is alkaline, which can significantly inhibit the formation of coke in the conversion process of the raw material furan alcohol or aldehyde compounds And inhibit the opening of the furan ring to form the target product with high selectivity; at the same time, the active component metal has a very good dispersion effect on the carrier, so that it exhibits high catalytic activity.

Preferably, in the method of the present invention, the furyl alcohol or aldehyde compound used is one or more selected from the following groups: furfuryl alcohol, furfural, C _1-6 alkyl substituted furfuryl alcohol, C _{1 -6} alkyl substituted furfural, 5-hydroxymethylfurfural, 4-hydroxymethylfurfural, 2,5-furandimethanol and 2,5-furandicarbaldehyde, etc.

Although the method of the present invention has no particular limitation on the reaction temperature, preferably, in the method of the present invention, the temperature of the oxidation reaction is 0-250°C.

Although the method of the present invention has no special limitation on the reaction pressure, preferably, in the method of the present invention, the pressure of air or pure oxygen is 0.1-4 MPa.

Although the method of the present invention has no special limitation on the reaction time, preferably, in the method of the present invention, the oxidation reaction time is 1-24 hours, preferably 6-12 hours.

Preferably, in the method of the present invention, the temperature of the oxidation reaction is 0 to lower than 60° C. and the pressure of the air or pure oxygen is 0.1 to 0.5 MPa, so that the furan alcohol or aldehyde compound is selectively It is oxidized to furan aldehyde products without producing furan acid products.

Preferably, in the method of the present invention, the temperature of the oxidation reaction is 80-250° C. and the pressure of the air or pure oxygen is 1.0-4 MPa, so that the furan alcohol or aldehyde compound is selectively completely oxidized For furanic acid products.

Example

The present invention will be described in further detail below in conjunction with specific examples. In the following examples, if no special instructions, the methods used are conventional methods, and the reagents used can be obtained from commercial sources (for example, calcium hydroxyphosphate and ruthenium trichloride are purchased from Aladdin Reagent Company, acetic acid and some other metal salts are purchased from Sinopharm reagent companies, etc.). The embodiments described below are exemplary, and are only for explaining the present invention, and should not be construed as limiting the present invention.

Rotary evaporator: model: RE100-Pro, purchased from Anhui Kemi Machinery Technology Co., Ltd., turn on the rotary evaporator, connect the round bottom flask containing the catalyst solution to the interface of the rotary evaporator, set the temperature of the water bath to 45°C, and rotate Evaporate until the acetone of the dispersion is completely evaporated.

X-ray diffraction (XRD) instrument: Model: Smartlab, purchased from Shimadzu Corporation, Japan, put the catalyst solid powder on the test frame, set the diffraction angle range to 10 ° ~ 70 ° to scan, and obtain the sample diffraction curve.

High-resolution dark-field scanning electron microscope (HAADF-STEM) instrument: Model: Talos F200X, purchased from FEI Company in the United States, put the catalyst sample powder into ethanol solvent for ultrasonic dispersion, and then lower the dispersion liquid on the copper mesh carrier, and irradiate it with light Drying. After drying, fix the copper grid containing the sample on the sample holder, put it into the instrument and pump it to a vacuum environment, and perform electron transmission to obtain the shape information of the sample.

Liquid chromatograph: model: L-2455, purchased from Shimadzu Corporation, Japan. After diluting the reaction solution to be detected to a certain concentration, take 2mL of liquid and put it into a liquid phase detector, and flow it with 0.5% trifluoromethanesulfonic acid aqueous solution The phase separates the different products by flow, and the different products enter the detector after different times, and the detector gives the information of the different products.

Reactor: Model: 50mL Parr reactor, purchased from Anhui Kemi Machinery Technology Co., Ltd. Weigh a certain amount of reaction raw materials and catalysts and place them in the reactor, add 10mL of solvent, seal and fix the reactor, and carry out the aeration reaction.

Catalyst preparation

The supported metal catalyst used in the following examples can be prepared as follows:

Supported ruthenium catalyst _: In a _250mL round-bottomed flask container, impregnate 0.50-1.00g of different Apatite carrier (see Tables 1 and 2 below for details), after stirring at 25-55°C for 12-24h, remove the acetone dispersant by rotary evaporation, and air-dry at 20-100°C for 6-12h to obtain ruthenium The loaded ruthenium catalyst has a mass fraction of 0.5% to 5%.

Supported palladium catalyst: In a 250mL round bottom flask container, _0.50-1.00g of different apatite carriers ( See Tables 1 and 2 below for details), after stirring for 12 to 24 hours at 25 to 55°C, the acetone dispersant was removed by rotary evaporation, and dried at 20 to 100°C for 6 to 12 hours to obtain a palladium loading mass fraction of 0.5% to 5% supported palladium catalyst.

Other catalysts: similar to the preparation process of the above-mentioned supported ruthenium or palladium catalysts, catalysts with other single metals such as Ir, Pt, Co, Cu or Ni are prepared on different supports, or multiple metals such as selected from Ru, A catalyst of a combination of two or more of Pd, Ir, Pt, Co, Cu and Ni (see Tables 1 and 2 below for details).

For the carrier used in the present invention and the prepared catalyst, X-ray diffraction (XRD) instrument and HAADF-STEM are used for detection. Fig. 1 shows the calcium hydroxyphosphate (Ca ₅ (PO4) ₃ (OH), HAP) carrier used according to the present invention and the catalyst Pd prepared on it by impregnation method palladium (Pd) and ruthenium (Ru) -HAP (Fig. 1 (a)) and Ru-HAP (Fig. 1 (a)) catalyst XRD curve figure, in Fig. 1 (a) and (b) represents calcium hydroxyphosphate diffraction peak, palladium and Ruthenium species diffraction peaks. As shown in Figure 1, the comparison of the morphology before and after loading the metal on the hydroxyapatite carrier shows that no metal species is observed in the XRD spectrum of the hydroxyapatite after loading the metal palladium (Pd) or ruthenium (Ru). Diffraction peaks, which shows that the metal is very uniformly dispersed on the carrier HAP, and also shows that the stability of the morphology and structure of the hydroxyapatite carrier is very good. 2 shows HAADF-STEM images of catalysts Pd-HAP (a) and Ru-HAP (b) prepared by impregnating palladium (Pd) and ruthenium (Ru) thereon according to the present invention. It can be seen from the dark-field electron microscope image in Figure 2 that after the metal palladium (Pd) and ruthenium (Ru) are loaded on the carrier HAP, the metal palladium (Pd) and ruthenium (Ru) are very uniformly dispersed on the carrier HAP, and the metal palladium (Pd) and ruthenium (Ru) are dispersed very uniformly on the carrier HAP. The size of the metal on the stone support is also very fine.

Examples 1-8

Using the above method, the active metals Ru, Pd, Pt, Ir, Co, Cu and Ni were respectively supported on apatite supports Ca ₅ (PO ₄ ) ₃ (OH), Mg ₂ Ca ₃ (PO ₄ ) ₃ (OH) , Ce ₅ (VO ₄ ) ₆ (OH) ₂ , Ca ₅ (PO ₄ ) ₃ (HCO ₃ ), Na ₁₀ (PO ₄ ) ₃ (OH), Ca ₅ (PO ₄ ) ₃ F or Na ₁₀ (PO ₄ ) ₃ (OH), thus obtaining the corresponding supported catalyst (see Table 1 for details). These catalysts were respectively used at 150°C and 1MPa oxygen in water solvent for 3h to catalyze the oxidation of HMF to prepare FDCA.

Specifically, 50 mg of HMF was added to a 50 mL reactor, and in the presence of the metal-loaded catalyst, 10 mL of water was added, the high-pressure oxygen cylinder was connected to the reactor, and the reactor was replaced by 6 inflation and deflation processes. Finally, set the oxygen pressure gauge to 1MPa by controlling the rotation of the pressure reducing valve, and use the programmed temperature control heating mantle to heat to 150°C. Under the condition of magnetic stirring, after 6 hours of reaction, put the high pressure reactor into a cold water bath for cooling After cooling, the pressure in the reactor was vented, and the mixture of the catalyst and the reaction solution was filtered with a filter membrane to separate the catalyst from the reaction solution. After the reaction solution was diluted with water to a certain concentration, shake well and sample 2mL for detection and analysis. spectrum analysis. The liquid chromatography analysis results of the three repeated experiments are shown in Table 1.

Examples 9-14

Using metal-loaded catalysts with different metal loadings (0.5-5% by mass), at 100° C., 2 MPa hydrogen, in n-hexane solvent, reacted for 15 h, and catalyzed the oxidation of HMF to prepare FDCA.

Specifically, 50 mg of HMF was added to a 50 mL reactor, and in the presence of the metal-loaded catalyst, 10 mL of n-hexane was added, the high-pressure oxygen cylinder was connected to the reactor, and the reactor was subjected to 6 inflation and deflation processes. Ventilate, and finally set the oxygen pressure gauge to 2MPa by controlling the rotation of the pressure reducing valve, and use the programmed temperature control heating mantle to heat to 100°C. Under the condition of magnetic stirring, after 15 hours of reaction, put the autoclave into the cold water bath for After cooling, vent the pressure in the reaction kettle, filter the mixture of catalyst and reaction solution with a filter membrane to separate the catalyst from the reaction solution, dilute the reaction solution with water to a certain concentration, shake well and sample 2mL for detection and analysis, use liquid Phase chromatography analysis. The liquid chromatography analysis results of the three repeated experiments are shown in Table 1.

Examples 15-27

Use different metals Ru, Pd, Ir, Co, Cu, Ni or their combination Pd-Ir, Pd-Cu, Ru-Co, Cu-Co, Pd-Ni to load on the apatite carrier respectively (active component The metal-supported catalyst prepared by the loading amount of 1% by weight) was reacted for 4 hours at 80° C. and 2 MPa air in a γ-butyrolactone (GBL) solvent to catalyze the oxidation of HMF to prepare FDCA.

Specifically, 50 mg of HMF was added to a 50 mL reactor, and in the presence of the metal-supported catalyst, 10 mL of GBL was added, the high-pressure air bottle was connected to the reactor, and the reactor was replaced by 6 inflation and deflation processes. Finally, set the air pressure gauge to 2MPa by controlling the rotation of the pressure reducing valve, and use the programmed temperature control heating mantle to heat to 80°C. Under the condition of magnetic stirring, after 24 hours of reaction, put the high pressure reactor into a cold water bath for cooling After cooling, the pressure in the reactor was vented, and the mixture of the catalyst and the reaction solution was filtered with a filter membrane to separate the catalyst from the reaction solution. After the reaction solution was diluted with water to a certain concentration, shake well and sample 2mL for detection and analysis. spectrum analysis. The liquid chromatography analysis results of the three repeated experiments are shown in Table 1.

Examples 28-40

Metal-supported catalysts prepared by using different metals Ru, Pd, Ir, Pt, Co or Cu loaded on the apatite carrier (the loading amount of the active component is 2% by mass), at 140 ° C, 3 MPa air, in In different solvents, react for 10 h to catalyze the oxidation of furfural to prepare furoic acid.

Specifically, add 50 mg furfural in a 50 mL reactor, in the presence of the metal-loaded catalyst, add 10 mL of solvent, connect the high-pressure air bottle to the reactor, and perform 6 inflation and deflation processes to ventilate the reactor , and finally set the air pressure gauge to 3MPa by controlling the rotation of the pressure reducing valve, and use the programmed temperature control heating mantle to heat to 140°C. Under the condition of magnetic stirring, after reacting for 10 hours, put the high-pressure reactor into a cold water bath for cooling. After cooling, the pressure in the reaction kettle was vented, and the mixture of the catalyst and the reaction solution was filtered with a filter membrane to separate the catalyst from the reaction solution. After the reaction solution was diluted with water to a certain concentration, shake well and sample 2mL for detection and analysis. analyze. The liquid chromatography analysis results of the three repeated experiments are shown in Table 1.

Examples 41-51

Metal-loaded catalysts prepared by using different metals Ru, Pd, Ir, Co or Cu loaded on the apatite carrier (the loading amount of the active component is 5% by mass), at different temperatures (0-200°C) , 1MPa oxygen, water as solvent, reaction 12h, catalytic oxidation of HMF to prepare FDCA.

Specifically, add 100mgHMF to a 50mL reactor, and in the presence of the metal-loaded catalyst, add 10mL of water, connect the high-pressure oxygen cylinder to the reactor, and carry out 6 inflation and deflation processes to ventilate the reactor , and finally set the oxygen pressure gauge to 1MPa by controlling the rotation of the pressure reducing valve, and use the programmed temperature control heating mantle to heat to the set temperature (see Table 1 for details). Under magnetic stirring conditions, after 12 hours of reaction, the high-pressure reactor Put it in a cold water bath for cooling. After cooling, vent the pressure in the reaction kettle. Use a filter membrane to filter the mixture of the catalyst and the reaction solution to separate the catalyst from the reaction solution. Detection analysis, analysis by liquid chromatography, analysis by liquid chromatography. The liquid chromatography analysis results of the three repeated experiments are shown in Table 1.

Examples 52-57

Using a catalyst prepared by loading metals Cu, Ru, Pd, Pt, and Co on an apatite carrier, under different oxygen pressures (0.1-4MPa), at 140°C, in a mixed solvent of water + GVL, react for 8h, Preparation of FDCA by catalytic oxidation of 2,5-furandimethanol.

Specifically, 100 mg of 2,5-furandimethanol was added to a 50 mL reactor, and in the presence of the metal-loaded catalyst, 10 mL of water+GVL was added, and the high-pressure oxygen cylinder was connected to the reactor, and aeration was performed 6 times, During the deflation process, the reactor is ventilated, and finally the oxygen pressure is set to a specific pressure by controlling the rotation of the pressure reducing valve, and heated to 140°C with a programmed temperature control heating mantle. Under the condition of magnetic stirring, after 8 hours of reaction, the Put the high-pressure reaction kettle into a cold water bath for cooling. After cooling, vent the pressure in the reaction kettle. Use a filter membrane to filter the mixture of catalyst and reaction solution to separate the catalyst from the reaction solution. After the reaction solution is diluted with water to a certain concentration, shake it up and take a sample. 2mL is used for detection and analysis, and is analyzed by liquid chromatography. The liquid chromatography analysis results of the three repeated experiments are shown in Table 1.

Examples 58-65

Using a catalyst prepared by loading metals Pd, Pt, Ir, Ru, and Cu on an apatite-based carrier, at different reaction times (1~10h), at 160°C, 1MPa oxygen, in DMSO solvent, catalyze the oxidation of furfuryl alcohol to prepare furoic acid.

Specifically, add 100mg furfuryl alcohol in a 50mL reactor, in the presence of the metal-loaded catalyst, add 10mL of DMSO, connect the high-pressure oxygen cylinder to the reactor, and carry out 6 inflation and deflation processes to change the reactor Finally, set the oxygen pressure gauge to 1MPa by controlling the rotation of the pressure reducing valve, and use the programmed temperature control heating mantle to heat to 160°C. Under the condition of magnetic stirring, after the reaction set time, put the high pressure reactor into a cold water bath for cooling After cooling, the pressure in the reactor was vented, and the mixture of the catalyst and the reaction solution was filtered with a filter membrane to separate the catalyst from the reaction solution. After the reaction solution was diluted with water to a certain concentration, shake well and sample 2mL for detection and analysis. spectrum analysis. The results of the liquid chromatography analysis of the three repeated experiments are shown in Table 1.

Examples 66-74

Use the catalyst prepared by loading metal Ru, Pd, Pt, Ir, Co, Cu, Ru-Pd, Cu-Co, Pd-Pt on the apatite carrier, at 60～160℃, 2MPa air, in water+ The mixed solvent system of different organic solvents was reacted for 3 hours to catalyze the oxidation of HMF to prepare FDCA.

Specifically, 100mgHMF was added to a 50mL reactor, and in the presence of the metal-supported catalyst, in a mixed solvent of water+organic solvent, a high-pressure air bottle was connected to the reactor, and the process of inflation and deflation was carried out 6 times. The reaction kettle is ventilated, and finally the air pressure gauge is set to 2MPa by controlling the rotation of the pressure reducing valve, and the heating mantle is used to heat the temperature to a specific temperature. Under the condition of magnetic stirring, after 3 hours of reaction, the high-pressure reaction kettle is put into a cold water bath After cooling, the pressure in the reaction kettle was vented, and the mixture of the catalyst and the reaction solution was filtered with a filter membrane to separate the catalyst from the reaction solution. After the reaction solution was diluted with water to determine the concentration, shake well and sample 2mL for detection and analysis. Liquid chromatography analysis. The liquid chromatography analysis results of the three repeated experiments are shown in Table 1.

Table 1

From the reaction results in Table 1, in the presence of a catalyst prepared by a hydroxyapatite carrier with a specific composition, in the presence of organic catalysts such as water, alkanes, halogenated alkanes, lactones, ethers, sulfones, amides, etc. In a mixed solvent system composed of solvent or water and organic solvent, and under mild reaction conditions of higher temperature (not lower than 80°C) and pressure (oxygen or air not lower than 1MPa), catalyze furan alcohol or aldehyde compounds Furanic acid products can be prepared with high conversion rate and high selectivity.

Examples 75-86

Using a catalyst prepared by loading metal Ru, Pd, Pt, Ir, Co, Cu, Ni, Pd-Cu, Ru-Ni, Pt-Co on an apatite carrier, at 20-60°C, 0.1-1MPa air , in water, an organic solvent or a mixture solvent system of water and an organic solvent, react for 1-8 hours, and catalyze the oxidation of HMF to prepare DFF.

Specifically, add 100mg HMF into a 50mL reactor, in the presence of the metal-loaded catalyst, in water, an organic solvent or a mixture solvent system of water and an organic solvent, 0.1-1MPa air, at 20-60°C, Under the condition of magnetic stirring, react for 1 to 8 hours, put the high-pressure reactor into a cold water bath for cooling, after cooling, vent the pressure in the reactor, and use a filter membrane to filter the mixture of the catalyst and the reaction solution to separate the catalyst from the reaction solution. After diluting the reaction solution with water to determine the concentration, shake it up and sample 2mL for detection and analysis, and analyze it by liquid chromatography. The liquid chromatography analysis results of three repeated experiments are shown in Table 2.

Table 2

It can be seen from the reaction results in Table 2 that in the presence of a catalyst prepared by a metal supported on a hydroxyapatite carrier with a specific composition, in the presence of water, alkanes, halogenated alkanes, lactones, ethers, sulfones, amides, etc. In an organic solvent or a mixed solvent system composed of water and an organic solvent, and under mild reaction conditions of lower reaction temperature (not higher than 60°C) and pressure (not higher than 0.5MPa), furan alcohol or aldehyde compounds are catalyzed The furan aldehyde products can be prepared with high conversion rate and high selectivity.

From the reaction results in Table 1 and Table 2, it can be seen that in the presence of a catalyst prepared by a hydroxyapatite carrier with a specific composition, in the presence of water, alkanes, halogenated alkanes, lactones, ethers, sulfones , amides and other organic solvents or a mixed solvent system composed of water and organic solvents, and the reaction temperature and pressure are controlled. The present invention realizes the preparation of catalyzed furan alcohol or aldehyde compounds with high conversion rate and high selectivity under mild reaction conditions. Fufural or acid products are obtained.

Therefore, in the presence of a supported catalyst prepared by an impregnation method with a hydroxyapatite carrier having a specific composition and a metal (Ru, Pd, Ir, Pt, Co, Cu, Ni or a combination thereof), the present invention can Under conditions (such as 20-160°C, 0.1-2MPa oxygen or air, reaction 1-12h), it can catalyze the oxidation reaction of furan alcohol or aldehyde compound with high conversion rate (up to 100%), high selectivity (up to 100%) ) to obtain furan aldehyde or acid products, thereby realizing a simple, green and efficient catalyst to catalyze furan alcohol or aldehyde compounds under milder conditions to catalyze a new method for preparing furan aldehyde or acid products by highly selective oxidation , which can better meet the needs of industrial applications.

In addition, the process of preparing furan aldehyde or acid products by the method of the present invention is simple, the reaction equipment is simple, the operation is simple, no additional alkali is needed, the reaction conditions are mild, the catalyst is cheap and easy to obtain, the product is easily separated from the catalyst and the solvent system, and the catalyst is hydrothermally Good stability, short reaction cycle, suitable for industrial production, has very broad application prospects.

The above is only an exemplary embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and any changes or replacements that are not conceived through creative work shall be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope defined in the claims.

Claims (10)

1. a kind of method that furyl alcohol or aldehyde compound is selectively oxidized to furan aldehyde or furan acid product, described method comprises making furyl alcohol or aldehyde compound in solvent with air or pure in the presence of catalyst Oxygen undergoes an oxidation reaction to obtain the desired product, Wherein the solvent is selected from water, an organic solvent or a mixed solvent composed of water and an organic solvent, and the organic solvent is selected from the group consisting of alkanes, halogenated alkanes, aromatic hydrocarbons, esters, ethers, sulfones and amides solvents one or more of The catalyst is a supported metal catalyst whose active component is supported on a carrier having the general formula _Ma ( _XOb ) _c (Z) _d , wherein M is one selected from Ca, Mg, Ce, Na and K or more; X is one or more selected from Si, P, S, V and As; Z is one or more selected from the counter group OH, CO ₃ , HCO ₃ , F and Cl a, b, c and d are each independently selected from an integer of 1 to 10 under the condition of maintaining the charge balance of the general formula, and the active component is selected from Group VIIIB and Group IB of the Periodic Table of Elements one or more of the transition metals. 2. The method according to claim 1, characterized in that, said furyl alcohol or aldehyde compound is one or more selected from the following composition groups: furfuryl alcohol, furfural, C _1-6 alkyl substitution Furfuryl alcohol, C _1-6 alkyl substituted furfural, 5-hydroxymethylfurfural, 4-hydroxymethylfurfural, 2,5-furandimethanol and 2,5-furandicarbaldehyde. 3. The method according to claim 1, wherein the active component is one or more selected from Ru, Pd, Ir, Pt, Co, Cu and Ni. 4. The method according to claim 1, characterized in that, based on the total mass of the catalyst, the loading of the active component is 0.1-30%. 5. The method according to claim 1, wherein the organic solvent is selected from normal hexane, octane, 1,4-dioxane, tetrahydrofuran, dichloromethane, ethyl acetate, dimethyl ethylene One or more of sulfone, N,N-dimethylformamide, γ-butyrolactone and γ-valerolactone. 6. The method according to claim 1, characterized in that the temperature of the oxidation reaction is 0-250°C. 7. The method according to claim 1, characterized in that the pressure of the air or pure oxygen is 0.1-4 MPa. 8. The method according to claim 1, characterized in that, the time of the oxidation reaction is 1-24 hours. 9. method according to claim 1, is characterized in that, the temperature of described oxidation reaction is 0 to be lower than 60 ℃ and the pressure of described air or pure oxygen is 0.1～0.5MPa, thereby described furyl alcohol or Aldehydes are selectively oxidized to furan aldehydes without producing furan acids. 10. method according to claim 1, is characterized in that, the temperature of described oxidation reaction is 80～250 ℃ and the pressure of described air or pure oxygen is 1.0～4MPa, thereby described furyl alcohol or aldehyde compound Selective complete oxidation to furanic acid products.