A method for efficiently preparing 1,5-pentanediol based on M-M'Ox non-precious metal catalyst

Abstract

The present invention relates to a method for efficiently catalyzing the preparation of 1,5-pentanediol based on an M-M'Ox non-precious metal catalyst. The present invention constructs a uniform M-M'Ox nano-synergistic catalytic site with the help of a metal organic framework material, utilizes a second metal M' and a metal center M ortho-position distribution, strengthens the hydrogenation activity of the highly dispersed M metal center and the adsorption anchoring of the adjacent M'Ox site to the reactant molecules, and regulates the adsorption configuration and ring-opening rate of furfural and its derivative molecules. The catalyst of the present invention has a higher specific surface area than ordinary metal oxide catalysts, can expose more accessible metal centers as hydrogenation sites, and improves the catalytic activity of the catalyst in the reaction process of furfuryl alcohol to prepare 1,5-pentanediol; compared with conventional metal oxide catalysts, it has a richer pore structure, overcomes the mass transfer limitation caused by the pore structure in traditional catalysts, thereby improving the reaction rate of the catalyst.

Description

Technical Field

[0001] The invention relates to a method for efficiently preparing 1,5-pentanediol based on an M-M'Ox non-noble metal catalyst, belonging to the technical field of catalysts. Background Art

[0002] As an important chemical raw material, 1,5-pentanediol, due to its excellent chemical stability, is widely used in saturated / unsaturated polyesters / polyurethanes, lipids used in lubricants, elastomer plasticizers, advanced lubricant additives, and organic synthesis intermediates. 1,5-pentanediol is also an excellent solvent, widely used in the preparation of textiles, pharmaceuticals, pesticides, and plastics, as well as in the selective separation of cycloalkyl hydrocarbons and aromatics. With the continuous development of society and the economy, the industrial demand for 1,5-pentanediol is growing rapidly. However, the current industrial production process is cumbersome, production capacity is low, and costs are high, making it difficult to meet increasingly stringent environmental protection requirements. Therefore, the efficient synthesis of 1,5-pentanediol has broad development prospects and application value.

[0003] Chinese patent document CN1565728A discloses a catalyst and method for hydrogenating 1,5-pentanediol from dimethyl 1,5-pentanediate. The method uses a mixed dibasic acid as a raw material to prepare mixed dibasic acid dimethyl ester, which is then distilled to obtain dimethyl glutarate. The dimethyl glutarate is then hydrogenated using a copper chromate catalyst at 150-350°C and 3-5 MPa to prepare 1,5-pentanediol. This method uses a copper chromate catalyst during the preparation process, which involves a complex separation and purification process, and the environmental pollution caused by the chromium element cannot be ignored. Chinese patent document CN114524707 improves on the above technology by esterifying the mixed dibasic acid with a high-carbon fatty alcohol with a carbon number ≥4 without the use of a catalyst. Water and the raw material liquid are separated by boiling point difference, avoiding separation and purification of the esterification reaction liquid and increasing the yield of 1,5-pentanediol. The improved process route has been simplified, but due to the scarcity of C5 raw materials derived from fossil energy, the corrosiveness of acidic intermediates to equipment, and excessively high hydrogenation pressure, its technical barriers are relatively high. There is an urgent need to develop a process route for the efficient, green, and sustainable synthesis of 1,5-pentanediol under mild conditions.

[0004] Currently, biomass-based 1,5-pentanediol production can overcome many of the shortcomings of the petrochemical route. Furfural, a bulk chemical derived from agricultural waste, is currently the only chemical raw material fully derived from agricultural and forestry waste. The development of furfural derivatives has become a key focus of the furfural downstream industry chain. The effective utilization of furfural not only reduces dependence on petroleum resources but also increases the added value of agricultural products. Furfural and its derivatives are all C5 molecules and are oxygen-rich. Therefore, the preparation of 1,5-pentanediol from furfural and its derivatives is highly atom-economical, simple, and requires no oxidant. However, the main challenges of current research are the high cost of precious metal catalysts and the low reaction efficiency, product yield, and poor stability of non-precious metal catalysts.

[0005] Therefore, there is an urgent need for a new method for preparing 1,5-pentanediol using furfural and its derivatives as raw materials through high-performance catalysis. Summary of the Invention

[0006] In view of the deficiencies in the prior art, the present invention provides a method for preparing 1,5-pentanediol with high catalytic efficiency based on an M-M'Ox non-precious metal catalyst.

[0007] The present invention uses a dual-functional site catalyst with uniformly distributed catalytic centers and both metal hydrogenation sites and reactant molecule adsorption sites. The adsorption sites are utilized to change the adsorption configuration of furfural and furfuryl alcohol on the catalyst, and the metal hydrogenation sites are utilized to achieve highly selective hydrogenation ring-opening of the C2-O1 bond of the furan ring, thereby achieving direct hydrogenation of furfural or its derivatives into 1,5-pentanediol under mild conditions, thereby improving the reaction efficiency and increasing the yield of 1,5-pentanediol in the product, thereby achieving the dual optimization goals of high 1,5-pentanediol reaction efficiency and high product yield.

[0008] The technical solutions of the present invention are as follows:

[0009] A method for preparing 1,5-pentanediol by hydrogenating furfural or its derivatives comprises the following steps: using furfural or its derivatives as a reaction raw material, a water / fatty alcohol mixed system as a reaction medium, reacting for 1 to 5 hours under the action of an M-M'Ox non-precious metal catalyst at a reaction temperature of 100 to 180° C. and an initial hydrogen pressure of 1 to 8 MPa, thereby synthesizing 1,5-pentanediol in one step.

[0010] According to the preferred embodiment of the present invention, the M-M'Ox non-precious metal catalyst is prepared as follows:

[0011] (1) dissolving a metal salt corresponding to a metal source M in a solvent a and stirring thoroughly until completely dissolved to obtain a solution A; dissolving an organic ligand in a solvent b and stirring thoroughly until completely dissolved to obtain a solution B; mixing solution A and solution B and stirring thoroughly; performing a thermal reaction or coprecipitation, cooling, centrifuging, washing, and drying to obtain a metal organic framework material;

[0012] (2) introducing the precursor corresponding to the metal M' into the metal organic framework material obtained in step (1) to obtain an M-M'Ox non-precious metal catalyst precursor;

[0013] (3) calcining the M-M'Ox non-noble metal catalyst precursor under the protection of an inert atmosphere to obtain the M-M'Ox non-noble metal catalyst.

[0014] According to the present invention, preferably, in step (1), the metal source M is cobalt or copper, the cobalt salt is one or a mixture of two or more of cobalt chloride, cobalt nitrate, cobalt sulfate, cobalt acetate, cobalt phosphate, cobalt bromide, and cobalt perchlorate; the copper salt is one or a mixture of two or more of copper chloride, copper nitrate, copper sulfate, copper acetate, copper bromide, copper perchlorate, and copper citrate.

[0015] According to the present invention, preferably, in step (1), the organic ligand is one or a mixture of two or more of 2-methylimidazole, terephthalic acid, 2,5-dihydroxyterephthalic acid, 2,5-diaminoterephthalic acid, trimesic acid, 4,4-diphenyl ether dicarboxylic acid, 4,4-bipyridine, 5,10,15,20-tetracarboxyphenylporphyrin, tetrakis(4-carboxyphenyl)ethylene, 1,3,6,8-tetrakis(4-carboxyphenyl)pyrene, 1,2,4,5-tetrakis(4-carboxyphenyl)benzene, and benzimidazole.

[0016] According to the preferred embodiment of the present invention, in step (1), the solvent a is one or a mixture of two or more of methanol, ethanol, deionized water or N,N-dimethylformamide; the solvent b is one or a mixture of two or more of methanol, ethanol, deionized water or N,N-dimethylformamide.

[0017] According to the preferred embodiment of the present invention, in step (1), the molar ratio of the metal element to the organic ligand in the metal source M is (0.5-30):(1-10).

[0018] According to the preferred embodiment of the present invention, in step (1), the molar ratio of the metal element in the metal source M to the solvent a is 0.5:(20-200).

[0019] Preferably according to the present invention, in step (1), the molar ratio of the organic ligand to the solvent b is 0.5:(20-1700).

[0020] According to a preferred embodiment of the present invention, in step (1), the thermal reaction is carried out at 60-200° C. for 10-72 hours.

[0021] According to the preferred embodiment of the present invention, in step (2), the metal M' is one or a mixture of two or more of magnesium, aluminum, zirconium, titanium, cobalt, nickel, copper and zinc.

[0022] According to a preferred embodiment of the present invention, in step (2), the method for introducing the metal species M' is to directly add it into the solvent a for co-growth, immersion or atomic layer deposition.

[0023] Preferably, according to the present invention, in step (3), the calcination atmosphere is one of nitrogen, argon, helium, a hydrogen-nitrogen mixture, a hydrogen-argon mixture, and a hydrogen-helium mixture.

[0024] According to the preferred embodiment of the present invention, in step (3), the calcination temperature is 250-1000° C., and the calcination time is 2-5 hours.

[0025] Preferably, according to the present invention, in step (3), the heating rate is 1-10°C / min.

[0026] According to the preferred embodiment of the present invention, in step (3), the calcination atmosphere flow rate is 1-500 mL / min; further preferably, the calcination atmosphere flow rate is 20-100 mL / min.

[0027] According to the present invention, preferably, the furfural derivative is furfuryl alcohol or tetrahydrofurfuryl alcohol.

[0028] Preferably, according to the present invention, the mass of furfural or its derivatives is 0.1 to 50% of the mass of the water / fatty alcohol mixture system, and the mass of the fatty alcohol is 20 to 100% of the total mass of the water / fatty alcohol mixture system; the fatty alcohol is any one of methanol, ethanol, isopropanol, n-propanol, and n-butanol; and the amount of the M-M'Ox non-precious metal catalyst is 1 to 50% of the mass of the furfural or its derivatives.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] 1. The present invention uses a metal-organic framework (MOF) material formed by a metal salt M and an organic ligand as a template. By introducing a second metal M' into the MOF material to achieve an ortho-distribution of the second metal M' and the metal center M, the MOF's inherent coordination bonds and pore confinement effects are utilized to construct uniform M-M'Ox nano-synergistic catalytic sites through heat treatment. By enhancing hydrogenation activity through highly dispersed hydrogenation centers M and adsorbing and anchoring reactant molecules using adjacent second metal sites M'Ox, the dual-center synergistic catalysis modulates the adsorption configuration and ring-opening rate of furfural and its derivatives, thereby improving their ring-opening efficiency and product selectivity.

[0031] 2. Compared with ordinary metal oxide catalysts, the catalyst used in the present invention is a metal organic framework material that undergoes partial structural changes during heat treatment to form a transitional state structure between MOFs and metal oxides. Compared with simple metal organic framework materials, it has highly dispersed metal active sites and stronger metal-support interactions; compared with conventional metal oxide catalysts, it has highly dispersed uniform nanocatalytic sites and rich pore structures. The catalyst derived from the metal-organic framework material used in the present invention has abundant pores inside, which can improve the mass transfer rate, expose more accessible catalytic sites, and improve the catalytic efficiency of the catalyst in the reaction process of preparing 1,5-pentanediol from furfural and its derivatives. By introducing a second metal M' into the metal-organic framework material, the spatial distance between the metal hydrogenation center M and the metal oxide adsorption center M'Ox can be shortened at the microscopic level, forming a favorable molecular adsorption-hydrogenation ring-opening configuration, thereby improving the synergistic catalytic effect, and facilitating the direct hydrogenation conversion of furfural or its derivatives into 1,5-pentanediol under mild conditions, thereby improving the reaction efficiency and increasing the yield of 1,5-pentanediol in the product, thereby achieving the dual optimization goals of high 1,5-pentanediol reaction efficiency and high product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Co-CoO prepared in Example 1 x Powder X-ray diffraction (PXRD) pattern of the catalyst;

[0033] Figure 2 Co-CoO prepared in Example 1 x Scanning electron microscope (SEM) images of the catalyst;

[0034] Figure 3 Co-CoO prepared in Example 1 x Fourier transform infrared (FT-IR) comparison of the catalyst, organic ligand, and MOF precursor;

[0035] Figure 4 The X-ray powder diffraction pattern (PXRD) of the Co-Al2O3 catalyst prepared in Example 2;

[0036] Figure 5 TEM image of the Co-Al2O3 catalyst prepared in Example 2;

[0037] Figure 6 This is a low-temperature nitrogen adsorption-desorption curve of the Co-Al2O3 catalyst prepared in Example 2;

[0038] Figure 7 This is the pore size distribution diagram of the Co-Al2O3 catalyst prepared in Example 2;

[0039] Figure 8 This is a performance comparison chart of Examples 1-3 and Comparative Examples 1 and 2;

[0040] Figure 9 Co-CoO prepared in Example 1 x Reaction kinetic data of the catalyst. Figure a is the reaction rate formula at different temperatures, and Figure b is the calculation of the reaction activation energy. The activation energy value calculated based on the reaction kinetics is 20.7kJ / mol. DETAILED DESCRIPTION

[0041] The present invention is further explained below with reference to specific examples and accompanying drawings, but the present invention is not limited thereto. The experimental methods described in the following examples are conventional methods unless otherwise specified; the instruments and materials described are commercially available unless otherwise specified.

[0042] Example 1:

[0043] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0044] Preparation of M-M'Ox non-precious metal catalysts:

[0045] (1) Weigh 0.46 g of cobalt nitrate and dissolve it in 45 mL of a mixed solution of N,N-dimethylformamide and ethanol (volume ratio = 3:1). Stir thoroughly until completely dissolved to obtain solution A. Weigh 0.048 g of the organic ligand 5,10,15,20-tetracarboxyphenylporphyrin and dissolve it in 20 mL of a mixed solution of N,N-dimethylformamide and ethanol (volume ratio = 3:1). Stir thoroughly until completely dissolved to obtain solution B. Solution A and solution B are mixed and stirred, placed in a polytetrafluoroethylene reactor, heated to 80°C, and reacted for 24 hours. After the reaction is completed, cool, centrifuge, wash, and dry to obtain the MOF precursor.

[0046] (2) The precursor prepared in step (1) was placed in a tube furnace, heated from room temperature to 450°C at 5°C / min under a hydrogen-argon mixed atmosphere for 4 hours, and then naturally cooled to obtain Co-CoO x Catalyst materials.

[0047] The obtained Co-CoO x The X-ray powder diffraction pattern of the catalyst is shown in Figure 1 As shown in the figure, no diffraction peak signal of Co species was detected in its XRD spectrum. This is because the Co species is highly dispersed in the catalyst. The large specific surface area unique to MOF makes the Co species evenly distributed on the catalyst surface, forming highly dispersed metal hydrogenation centers, which helps to improve the catalyst performance. Figure 2Scanning electron microscopy images show that the material has a flower-like morphology formed by the self-assembly of a two-dimensional sheet structure from bottom to top. Compared with general three-dimensional structure MOF, the MOF material with two-dimensional nanosheet self-assembly can increase the exposure and accessibility of the Co metal active center, thereby improving the catalyst performance. Figure 3 The infrared spectrum shows that after the MOF precursor is calcined at different temperatures, the coordination bonds between the organic ligands and the metal nodes gradually weaken as the temperature increases, indicating that only some of the coordination bonds in the calcined MOF are broken, forming a catalytic material in the transition state between MOF and metal oxide.

[0048] Catalytic hydrogenation of furfural derivatives:

[0049] Add 0.25g furfuryl alcohol, 40g ethanol and 0.05g Co-CoO x The catalyst was replaced three times by introducing nitrogen and hydrogen, and then hydrogen was introduced to adjust the initial pressure to 3 MPa. The autoclave was heated to 170°C and reacted for 1.5 hours. The reaction was stopped and the temperature was quickly cooled to room temperature. The vent valve was opened to reduce the pressure in the autoclave to atmospheric pressure. The furfuryl alcohol conversion rate was 97.2%, the 1,5-pentanediol yield was 45%, and the 1,5-pentanediol selectivity was 46%.

[0050] Figure 9 Co-CoO x The reaction kinetic data of the catalyst, based on the activation energy value of 20.7 kJ / mol calculated according to the reaction kinetics, indicate that the catalyst used in the present invention regulates the adsorption configuration and ring-opening rate of furfural / alcohol molecules through dual-center synergistic catalysis, thereby improving its ring-opening efficiency and product selectivity.

[0051] Example 2:

[0052] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0053] Preparation of M-M'Ox non-precious metal catalysts:

[0054] (1) Weigh 5.82 g of cobalt nitrate and dissolve it in 100 mL of methanol to obtain solution A. Weigh 6.56 g of 2-methylimidazole and dissolve it in 100 mL of methanol to obtain solution B. Mix solution A and solution B and stir until they are clear. Let it stand for 24 h, filter and wash until the filtrate is clear and transparent. Dry it at 80 °C for 12 h to obtain the MOF precursor.

[0055] (2) Weigh 0.139 g of aluminum nitrate and dissolve it in water. Stir and form a transparent impregnation solution. Weigh 0.2 g of MOF precursor and impregnate it with equal volume. Let the impregnated sample stand for 12 h and dry it at 80 °C for 12 h to obtain impregnated sample C.

[0056] (3) Sample C was placed in a tube furnace, heated to 500°C at 5°C / min under an argon atmosphere, kept at this temperature for 2 h, and then naturally cooled to room temperature to obtain the Co-Al2O3 catalyst material;

[0057] The X-ray powder diffraction pattern of the prepared Co-Al2O3 catalyst is shown in Figure 4 The calcined Co-Al2O3 catalyst showed no characteristic diffraction peaks of cobalt species and alumina, indicating that under the confinement of the MOF precursor, the elemental cobalt was highly dispersed nanoparticles and the adjacent alumina centers were also amorphous. Figure 5 Transmission electron microscopy images show that the average size of cobalt nanoparticles in the prepared Co-Al2O3 catalyst sample is about 8nm, and lattice fringes of the Co(1,1,1) crystal plane can be observed. This indicates that highly dispersed metal cobalt nanoparticles can be formed under the coordination of organic ligands in the MOF precursor. Figure 6 The nitrogen adsorption-desorption isotherm shows that the material forms mesopores that are beneficial to mass transfer while retaining the micropores of the MOF structure. Figure 7 It can be seen that the specific surface area of ​​the material is 440m 2 ·g -1 The pore size is concentrated in the range of 5-10 nm, and the pore structure is much larger than that of non-precious metal catalysts suitable for this reaction.

[0058] Catalytic hydrogenation of furfural derivatives:

[0059] 0.4 g of furfuryl alcohol, 40 g of ethanol and 0.1 g of Co-Al2O3 catalyst were added to the reactor, and nitrogen and hydrogen were introduced for replacement three times each. Then, hydrogen was introduced to adjust the initial pressure to 2 MPa. The autoclave was heated to 160°C and reacted for 5 hours. The reaction was stopped and the temperature was cooled to room temperature. The vent valve was opened to reduce the pressure in the autoclave to atmospheric pressure. The furfuryl alcohol conversion rate was 91.2%, the 1,5-pentanediol yield was 40%, and the 1,5-pentanediol selectivity was 44%.

[0060] Example 3:

[0061] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0062] Preparation of M-M'Ox non-precious metal catalysts:

[0063] (1) 5.82 g of cobalt nitrate was weighed and dissolved in 100 mL of methanol to obtain solution A. 6.56 g of 2-methylimidazole was weighed and dissolved in 100 mL of methanol to obtain solution B. Solutions A and B were mixed and stirred until clear, then allowed to stand for 24 h. The filtrate was then filtered and washed until clear and transparent. The MOF precursor was then dried at 80°C for 12 h.

[0064] (2) Weigh 0.025 g of zirconium oxynitrate and dissolve it in water, stir and form a transparent impregnation solution, weigh 0.2 g of MOF precursor and impregnate it with equal volume. The impregnated sample is allowed to stand for 12 h, dried at 80 °C for 12 h, and ground to obtain impregnation sample C.

[0065] (3) Sample C was placed in a tube furnace, heated to 500°C at 5°C / min under an argon atmosphere, kept at that temperature for 2 h, and then naturally cooled to room temperature to obtain a Co-ZrO2 catalyst material.

[0066] The catalytic hydrogenation reaction of furfural derivatives was carried out according to Example 1.

[0067] Embodiment 4:

[0068] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0069] Preparation of M-M'Ox non-precious metal catalysts:

[0070] (1) 4.76 g of cobalt chloride was weighed and dissolved in 100 mL of methanol to obtain solution A. 6.56 g of 2-methylimidazole was weighed and dissolved in 100 mL of methanol to obtain solution B. Solutions A and B were mixed and stirred until clear, then allowed to stand for 24 h. The filtrate was filtered and washed until clear and transparent. The MOF precursor was dried at 80°C for 12 h.

[0071] (2) Weigh 0.048 g of tetraethyl titanate and dissolve it in ethanol. Stir and form a transparent impregnation solution. Weigh 0.2 g of MOF precursor and use equal volume impregnation. The impregnated sample is allowed to stand for 12 h, dried at 80 °C for 12 h, and ground to obtain impregnated sample C.

[0072] (3) Sample C was placed in a tube furnace, heated to 500°C at 5°C / min under an argon atmosphere, kept at that temperature for 2 h, and then naturally cooled to room temperature to obtain a Co-TiO2 catalyst material.

[0073] The catalytic hydrogenation reaction of furfural derivatives was carried out according to Example 1.

[0074] Example 5:

[0075] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0076] Preparation of M-M'Ox non-precious metal catalysts:

[0077] (1) 4.98 g of cobalt acetate was weighed and dissolved in 100 mL of methanol to obtain solution A. 6.56 g of 2-methylimidazole was weighed and dissolved in 100 mL of methanol to obtain solution B. Solutions A and B were mixed and stirred until clear, then allowed to stand for 24 h. The filtrate was then filtered and washed until clear and transparent. The MOF precursor was then dried at 80°C for 12 h.

[0078] (2) Weigh 0.045 g of zinc nitrate and dissolve it in water. Stir and form a transparent impregnation solution. Weigh 0.2 g of MOF precursor and use equal volume impregnation. The impregnated sample is allowed to stand for 12 h, dried at 80 °C for 12 h, and ground to obtain impregnation sample C.

[0079] (3) Sample C was placed in a tube furnace, heated to 500°C at a rate of 5°C / min under an argon atmosphere, kept at that temperature for 2 h, and then naturally cooled to room temperature to obtain a Co-ZnO catalyst material.

[0080] The catalytic hydrogenation reaction of furfural derivatives was carried out according to Example 1.

[0081] Example 6:

[0082] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0083] Preparation of M-M'Ox non-precious metal catalysts:

[0084] (1) 0.269 g of cobalt nitrate and 0.237 g of magnesium nitrate were weighed and dissolved in 34 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution A. 0.119 g of 2,5-dihydroxyterephthalic acid was weighed and dissolved in 17 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution B. Solutions A and B were mixed and stirred, placed in a polytetrafluoroethylene reactor, and heated to 120°C for 24 h. After the reaction, the mixture was cooled, filtered, washed, and dried to obtain a MOF precursor.

[0085] (2) The precursor prepared in step (1) was placed in a tube furnace, and the temperature was raised from room temperature to 500° C. at a rate of 5° C. / min under an argon atmosphere, kept for 2 h, and then naturally cooled to obtain a Co-MgO catalyst material.

[0086] Catalytic hydrogenation of furfural derivatives:

[0087] 2 g of furfuryl alcohol, 40 g of ethanol and 0.1 g of Co-MgO catalyst were added to the reactor, and nitrogen and hydrogen were introduced for replacement three times each. Then, hydrogen was introduced to adjust the initial pressure to 2.5 MPa. The autoclave was heated to 160°C and reacted for 3 hours. The reaction was stopped and the temperature was quickly cooled to room temperature. The vent valve was opened to reduce the pressure in the autoclave to atmospheric pressure. The furfuryl alcohol conversion rate was 95.47%, the 1,5-pentanediol yield was 36%, and the 1,5-pentanediol selectivity was 38%.

[0088] Example 7:

[0089] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0090] Preparation of M-M'Ox non-precious metal catalysts:

[0091] (1) 0.524 g of cobalt nitrate was dissolved in 34 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution A. 0.119 g of 2,5-dihydroxyterephthalic acid was dissolved in 17 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution B. Solutions A and B were mixed and stirred, placed in a polytetrafluoroethylene reactor, and heated to 120°C for 24 h. After the reaction, the mixture was cooled, filtered, washed, and dried to obtain a MOF precursor.

[0092] (2) Weigh 0.139 g of aluminum nitrate and dissolve it in water. Stir and form a transparent impregnation solution. Weigh 0.2 g of MOF precursor and use equal volume impregnation. The impregnated sample is allowed to stand for 12 h, dried at 80 °C for 12 h, and ground to obtain impregnation sample C.

[0093] (3) Sample C was placed in a tube furnace, heated to 500°C at a rate of 5°C / min under an argon atmosphere, kept at that temperature for 2 h, and then naturally cooled to room temperature to obtain the Co-Al2O3 catalyst material.

[0094] The catalytic hydrogenation reaction of furfural derivatives was carried out according to Example 1.

[0095] Example 8:

[0096] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0097] Preparation of M-M'Ox non-precious metal catalysts:

[0098] (1) 0.36 g of copper acetate was weighed and dissolved in 34 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution A. 0.119 g of 2,5-dihydroxyterephthalic acid was weighed and dissolved in 17 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution B. Solutions A and B were mixed and stirred, placed in a polytetrafluoroethylene reactor, and heated to 120°C for 24 h. After the reaction, the mixture was cooled, filtered, washed, and dried to obtain a MOF precursor.

[0099] (2) Weigh 0.025 g of zirconium oxynitrate and dissolve it in water, stir and form a transparent impregnation solution, weigh 0.2 g of MOF precursor and impregnate it with equal volume. The impregnated sample is allowed to stand for 12 h, dried at 80 °C for 12 h, and ground to obtain impregnation sample C.

[0100] (3) Sample C was placed in a tube furnace, heated to 500°C at a rate of 5°C / min under an argon atmosphere, kept at that temperature for 2 h, and then naturally cooled to room temperature to obtain a Co-ZrO2 catalyst material.

[0101] The catalytic hydrogenation reaction of furfural derivatives was carried out according to Example 1.

[0102] Example 9:

[0103] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0104] Preparation of M-M'Ox non-precious metal catalysts:

[0105] (1) 0.435 g of copper nitrate was dissolved in 34 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution A. 0.119 g of 2,5-dihydroxyterephthalic acid was dissolved in 17 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution B. Solutions A and B were mixed and stirred, placed in a polytetrafluoroethylene reactor, and heated to 120°C for 24 h. After the reaction, the mixture was cooled, filtered, washed, and dried to obtain a MOF precursor.

[0106] (2) Using isopropyl titanate and deionized water as precursor sources, TiO2 was deposited in the MOF precursor by atomic layer deposition at 100°C to obtain precursor C.

[0107] (3) Sample C was placed in a tube furnace, heated to 500°C at a rate of 5°C / min under an argon atmosphere, kept at that temperature for 2 h, and then naturally cooled to room temperature to obtain the Co-TiO2 catalyst material.

[0108] The catalytic hydrogenation reaction of furfural derivatives was carried out according to Example 1.

[0109] Example 10:

[0110] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0111] Preparation of M-M'Ox non-precious metal catalysts:

[0112] (1) 0.448 g of cobalt acetate was weighed and dissolved in 34 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution A. 0.119 g of 2,5-dihydroxyterephthalic acid was weighed and dissolved in 17 ml of a mixture of DMF: deionized water: anhydrous ethanol (15:1:1) to obtain solution B. Solutions A and B were mixed and stirred, placed in a polytetrafluoroethylene reactor, and heated to 120°C for 24 h. After the reaction, the mixture was cooled, filtered, washed, and dried to obtain a MOF precursor.

[0113] (2) Weigh 0.045 g of zinc nitrate and dissolve it in water. Stir and form a transparent impregnation solution. Weigh 0.2 g of MOF precursor and use equal volume impregnation. The impregnated sample is allowed to stand for 12 h, dried at 80 °C for 12 h, and ground to obtain impregnation sample C.

[0114] (3) Sample C was placed in a tube furnace, heated to 500°C at a rate of 5°C / min under an argon atmosphere, kept at that temperature for 2 h, and then naturally cooled to room temperature to obtain a Co-ZnO catalyst material.

[0115] The catalytic hydrogenation reaction of furfural derivatives was carried out according to Example 1.

[0116] Example 11:

[0117] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0118] Preparation of M-M'Ox non-precious metal catalysts:

[0119] (1) Weigh 1.82 g of copper nitrate and dissolve it in 50 ml of methanol to obtain solution A. Weigh 0.158 g of trimesic acid and dissolve it in 50 ml of methanol to obtain solution B. Mix solution A and solution B and stir until clear. Let it stand for 2 h, filter, and wash until the filtrate is clear and transparent. Dry at 80°C for 12 h to obtain the MOF precursor.

[0120] (2) Using trimethylaluminum and deionized water as precursor sources, Al2O3 was deposited in the MOF precursor by atomic layer deposition at 200°C to obtain precursor C.

[0121] (3) Sample C was placed in a tube furnace, heated to 400°C at a rate of 5°C / min in a hydrogen-argon mixed atmosphere, kept at that temperature for 2 h, and then naturally cooled to room temperature to obtain a Cu-Al2O3 catalyst material.

[0122] The catalytic hydrogenation reaction of furfural derivatives was carried out according to Example 1.

[0123] Example 12:

[0124] A method for preparing 1,5-pentanediol with high catalytic efficiency based on M-M'Ox non-precious metal catalyst

[0125] Preparation of M-M'Ox non-precious metal catalysts:

[0126] (1) Weigh 1.82 g of copper nitrate and dissolve it in 50 ml of methanol to obtain solution A. Weigh 0.158 g of trimesic acid and dissolve it in 50 ml of methanol to obtain solution B. Mix solution A and solution B and stir until clear. Let it stand for 2 h, filter, and wash until the filtrate is clear and transparent. Dry at 80°C for 12 h to obtain the MOF precursor.

[0127] (2) Weigh 0.045 g of zinc nitrate and dissolve it in water. Stir and form a transparent impregnation solution. Weigh 0.2 g of MOF precursor and use equal volume impregnation. The impregnated sample is allowed to stand for 12 h, dried at 80 °C for 12 h, and ground to obtain impregnation sample C.

[0128] (3) Sample C was placed in a tube furnace, heated to 400°C at a rate of 5°C / min in a hydrogen-argon mixed atmosphere, kept at that temperature for 2 h, and then naturally cooled to room temperature to obtain a Cu-ZnO catalyst material.

[0129] The catalytic hydrogenation reaction of furfural derivatives was carried out according to Example 1.

[0130] Comparative Example 1:

[0131] A method for preparing 1,5-pentanediol

[0132] Preparation of catalyst:

[0133] Mix 0.1 mol / L copper nitrate solution and aluminum nitrate to form Solution A. Add Solution A and 4 mol / L NaOH dropwise to a 0.5 mol / L Na2CO3 solution, maintaining the solution pH at approximately 10. Allow to stand at 30°C for 24 hours, then filter and wash the filtrate to a pH of approximately 7. After drying at 120°C for 12 hours, calcinate at 500°C in air for 4 hours to obtain the Cu-Al2O3 catalyst. Prior to the reaction, reduce the catalyst at 350°C in a H2 / Ar mixed atmosphere.

[0134] Catalytic hydrogenation of furfural derivatives:

[0135] 4 g of furfuryl alcohol, 36 g of ethanol and 0.2 g of Cu-Al2O3 catalyst were added to the reactor, and nitrogen and hydrogen were introduced for replacement three times each. Then, hydrogen was introduced to adjust the initial pressure to 6 MPa. The autoclave was heated to 140°C and reacted for 8 hours. The reaction was stopped and cooled to room temperature. The vent valve was opened to reduce the pressure in the autoclave to atmospheric pressure. The furfuryl alcohol conversion rate was 60.4%, the 1,5-pentanediol yield was 14%, and the 1,5-pentanediol selectivity was 22.7%.

[0136] By comparing Example 1 and Comparative Example 1, it can be seen that the M-M'Ox hydrogenation-adsorption dual-functional site catalyst constructed based on MOF materials shows better product selectivity and faster reaction efficiency than the conventional non-precious metal oxide catalyst in the comparative example. This is attributed to the fact that its rich internal pore structure is conducive to mass transfer, and the highly dispersed metal center formed strengthens the hydrogen activation and ring-opening process. The adjacent metal oxides can achieve precise adsorption and anchoring of the oxygen-containing functional groups of the reactant molecules, regulate the adsorption configuration, reduce the steric hindrance effect during the ring opening of 1,5-pentanediol, and facilitate the breaking of the C2-O1 bond in the furan ring, forming a synergistic catalytic effect with the metal center, and realizing the efficient and highly selective preparation of 1,5-pentanediol.

[0137] Comparative Example 2:

[0138] A method for preparing 1,5-pentanediol

[0139] Preparation of catalyst:

[0140] 5.82 g of cobalt nitrate was weighed and dissolved in 100 mL of methanol to obtain solution A. 6.56 g of 2-methylimidazole was weighed and dissolved in 100 mL of methanol to obtain solution B. Solutions A and B were mixed and stirred until clear, then allowed to stand for 24 hours. The filtrate was then filtered and washed until clear. The MOF precursor was dried at 80°C for 12 hours to obtain the MOF precursor. The MOF precursor was placed in a tube furnace and heated at 5°C / min to 500°C under an argon atmosphere. The temperature was then maintained for 2 hours and then naturally cooled to room temperature to obtain the catalyst.

[0141] Catalytic hydrogenation of furfural derivatives:

[0142] 0.4 g of furfuryl alcohol, 40 g of ethanol and 0.1 g of the above catalyst were added to the reactor, and nitrogen and hydrogen were introduced three times for replacement. Then, hydrogen was introduced to adjust the initial pressure to 2 MPa. The autoclave was heated to 160° C. and reacted for 5 hours. The reaction was stopped and the temperature was cooled to room temperature. The vent valve was opened to reduce the pressure in the autoclave to atmospheric pressure. The furfuryl alcohol conversion rate was 9.75%, the 1,5-pentanediol yield was 3.7%, and the 1,5-pentanediol selectivity was 38%.

[0143] The above embodiments are not intended to limit the present invention. In actual production, the process parameters and ratios can be multiplied to meet production needs. Under the guidance of the above embodiments 1-14, other combinations not shown can be easily realized by those skilled in the art.

[0144] It should be noted that any equivalent manner or obvious variation made by those skilled in the art under the guidance of this specification should fall within the scope of protection of the present invention.

Claims

1. A method for preparing 1,5-pentanediol by hydrogenation of furfural or its derivatives, the method comprising the following steps: using furfural or its derivatives as a reaction raw material, a water / fatty alcohol mixture as a reaction medium, reacting for 1 to 5 hours at a reaction temperature of 100 to 180° C. and an initial hydrogen pressure of 1 to 8 MPa in the presence of an M-M'Ox non-precious metal catalyst, to synthesize 1,5-pentanediol in one step; The M-M'Ox non-precious metal catalyst is prepared as follows: (1) dissolving the metal salt corresponding to the metal source M in solvent a, stirring thoroughly until completely dissolved to obtain solution A, dissolving the organic ligand in solvent b, stirring thoroughly until completely dissolved to obtain solution B, mixing solution A and solution B, stirring thoroughly, cooling, centrifuging, washing, and drying after thermal reaction or coprecipitation to obtain a metal organic framework material; the metal source M is cobalt or copper, the cobalt salt is one or a mixture of two or more of cobalt chloride, cobalt nitrate, cobalt sulfate, cobalt acetate, cobalt phosphate, cobalt bromide, and cobalt perchlorate; the copper salt is copper chloride, copper nitrate, copper sulfate, and acetate. A mixture of one or more of copper, copper bromide, copper perchlorate, and copper citrate; the organic ligand is a mixture of one or more of 2-methylimidazole, terephthalic acid, 2,5-dihydroxyterephthalic acid, 2,5-diaminoterephthalic acid, trimesic acid, 4,4-diphenyl ether dicarboxylic acid, 4,4-bipyridine, 5,10,15,20-tetracarboxyphenylporphyrin, tetrakis(4-carboxyphenyl)ethylene, 1,3,6,8-tetrakis(4-carboxyphenyl)pyrene, 1,2,4,5-tetrakis(4-carboxyphenyl)benzene, and benzimidazole; (2) introducing a precursor corresponding to the metal M' into the metal organic framework material obtained in step (1) to obtain an M-M'Ox non-precious metal catalyst precursor; the metal M' is one or a mixture of two or more of magnesium, aluminum, zirconium, titanium, cobalt, nickel, copper, and zinc, and the method for introducing the metal species M' is a co-growth method, an immersion method, or an atomic layer deposition method by directly adding the metal species M' into the solvent a; (3) calcining the M-M'Ox non-precious metal catalyst precursor under the protection of an inert atmosphere to obtain the M-M'Ox non-precious metal catalyst.

2. The method according to claim 1, characterized in that In step (1), the solvent a is one or a mixture of two or more of methanol, ethanol, deionized water or N,N-dimethylformamide; the solvent b is one or a mixture of two or more of methanol, ethanol, deionized water or N,N-dimethylformamide.

3. The method according to claim 1, characterized in that In step (1), the molar ratio of the metal element to the organic ligand in the metal source M is (0.5-30):(1-10).

4. The method according to claim 1, wherein In step (1), the molar ratio of the metal element in the metal source M to the solvent a is 0.5:(20-200), the molar ratio of the organic ligand to the solvent b is 0.5:(20-1700), and the thermal reaction is carried out at 60-200°C for 10-72 hours.

5. The method according to claim 1, wherein In step (3), the calcination atmosphere is one of nitrogen, argon, helium, hydrogen-nitrogen mixture, hydrogen-argon mixture, and hydrogen-helium mixture; the calcination temperature is 250-1000°C, the calcination time is 2-5 hours, the heating rate is 1-10°C / min, and the calcination atmosphere flow rate is 1-500 mL / min.

6. The method according to claim 1, characterized in that The furfural derivative is furfuryl alcohol or tetrahydrofurfuryl alcohol.

7. The method according to claim 1, characterized in that The mass of furfural or its derivatives is 0.1-50% of the mass of the water / fatty alcohol mixture system, and the mass of the fatty alcohol is 20-100% of the total mass of the water / fatty alcohol mixture system; the fatty alcohol is any one of methanol, ethanol, isopropanol, n-propanol, and n-butanol; and the amount of the M-M'Ox non-precious metal catalyst is 1-50% of the mass of the furfural or its derivatives.

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