Preparation method and application of furfuryl alcohol hydrogenation catalyst

Abstract

The invention discloses a preparation method and application of a furfuryl alcohol hydrogenation catalyst, and relates to the technical field of furfuryl alcohol hydrogenation catalyst.The preparation method comprises the steps that zinc oxide is used as a carrier, an in-situ hydrotalcite structure is synthesized on the surface of the carrier in a hydrothermal mode, and alkaline sites on the surface of the catalyst are regulated and controlled by adding rare earth metal elements; and the active component has good loading dispersity, so that the reaction stability is improved, and the selectivity can be highly guaranteed. Zinc oxide is used as a carrier, an in-situ hydrotalcite-like structure is subjected to hydro-thermal synthesis, the specific surface area of the carrier is increased, and precious metal Pt is further dispersed; by adding rare earth metal elements, alkaline sites on the surface of the catalyst are regulated and controlled, and anchoring of precious metal is promoted; pt interacts with the surface of the hydrotalcite structure, so that the reaction stability is improved, and the selectivity can be highly guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of furoic alcohol hydrogenation catalyst preparation, and particularly relates to a preparation method and application of a furoic alcohol hydrogenation catalyst. BACKGROUND

[0002] 1,2-pentanediol is an important fine chemical intermediate, which is widely used in propiconazole fungicide synthesis, cosmetic additives and polymer material preparation. At present, the industrial production mainly adopts the petroleum-based 1-pentene method, which has problems of excessive use of formic acid, by-product sodium formate and high raw material cost, and is seriously dependent on non-renewable resources. In recent years, the synthetic route taking biomass-derived furoic alcohol as raw material has attracted much attention due to its renewable and environment-friendly advantages. However, the existing catalytic system has obvious defects: the non-noble metal catalysts (such as Cu, Ni, etc.) have poor stability and are easy to be deactivated; the noble metal catalysts (such as Pd, Ru, etc.) have high activity, but have problems of high cost and insufficient selectivity.

[0003] ①Chinese patent CN 103864575A discloses a method for preparing 1,2-pentanediol by 1-pentene hydration (petroleum chemical route), which uses formic acid in the reaction process, and has problems of equipment corrosion and excessive by-products.

[0004] ②Chinese patent CN102924232B discloses a method for directly preparing 1,2-pentanediol from furoic alcohol, which uses a copper-based catalyst for hydrogenation reaction in a fixed bed. The non-noble metal catalyst has a high usage amount, and the selectivity of 1,2-pentanediol is low, which is not conducive to subsequent separation operation.

[0005] ③Chinese patent CN104815653 introduces a preparation method of a composite catalyst for ring-opening hydrogenation of furan derivatives, which uses a Pt-based catalyst for hydrogenation reaction in a kettle type reaction kettle. The selectivity of 1,2-pentanediol is low, the content of noble metal is high, and the cost is difficult to control.

[0006] In view of the poor reaction performance of the existing catalysts and the difficulty in industrialization, the present application aims to provide a supported noble metal catalyst and a preparation method, and the catalyst prepared by the method has high stability and high selectivity, and can be used for continuous hydrogenation reaction. SUMMARY

[0007] The present application aims to: in order to solve the above problems, a preparation method and application of a furoic alcohol hydrogenation catalyst are provided.

[0008] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme: the technical scheme includes:

[0009] One: using zinc oxide as the carrier, in-situ hydrothermal synthesis of hydrotalcite structure on the surface of the carrier, by adding rare earth metal elements, regulating the basic sites on the surface of the catalyst, the active component has good dispersion, the stability of the reaction is improved, and the selectivity is also guaranteed.

[0010] Two: high dispersion of Pt particles increases the active center, and high conversion rate is obtained at low loading; the surface modified hydrotalcite structure attracts furfuryl alcohol through its basic sites, breaks the C-O bond, and increases the proportion of 1,2-pentanediol generated; the catalyst is used in a fixed bed, and the stability is steadily improved.

[0011] Three: the carrier used is zinc oxide, basic oxides such as magnesium oxide; aluminum salt and magnesium salt are nitrate and hydrochloride; the platinum source chemical reagent is ruthenium chloride hydrate; in addition, the assistant is cerium nitrate compound. The mass of the active component and the assistant respectively accounts for 1-3% and 0.5-5% of the mass of the catalyst.

[0012] Comparative Example 1:

[0013] Take 5g Al2O3 carrier, load 2% of metal platinum (platinum source is chloroplatinic acid), ultrasonic equal volume impregnation, then stand for 6h, 110℃ drying for 6h, increase from room temperature to 380℃ at 3℃ / min, calcine for 3h to obtain the catalyst.

[0014] Comparative Example 2:

[0015] Under the same preparation conditions as Comparative Example 1, replace the ZnO carrier with the Al2O3 carrier, and the remaining steps are completely consistent with Comparative Example 1, to prepare the Pt / Al2O3-ZnO catalyst for performance comparison.

[0016] Example 1:

[0017] 5.03g Mg(NO3)2·9H2O, 5.94g CO(NH2)2 is dissolved in 80mL deionized water, then 10g Al2O3 particles are added, stirred at room temperature for 30min, then transferred to a 100mL hydrothermal kettle with a polytetrafluoroethylene liner, reacted at 130℃ for 12h, washed with water and dried to obtain the MgAlLDHs@Al2O3 carrier. Take 5g of the carrier, load 2% of metal platinum (platinum source is chloroplatinic acid), ultrasonic equal volume impregnation, then stand for 6h, 110℃ drying for 6h, increase from room temperature to 380℃ at 3℃ / min, calcine for 3h to obtain the catalyst.

[0018] Example 2:

[0019] Similar to Example 1, MgO was used as the support. 2.64 g of Al(NO3)3·9H2O, 3.76 g of CO(NH2)2was dissolved in 80 mL of deionized water, and then 10 g of MgO particles were added, stirred at room temperature for 30 min, and then transferred to a 100 mL hydrothermal kettle with a polytetrafluoroethylene liner. The reaction was carried out at 130°C for 12 h, and after washing with water and drying, MgAlLDHs@MgO support was obtained. 5 g of the support was taken, and 2% of platinum (platinum source was chloroplatinic acid) was loaded by ultrasonic volume impregnation, then placed for 6 h, dried at 110°C for 6 h, and then calcined at 380°C for 3 h at a rate of 3°C / min from room temperature to obtain the catalyst.

[0020] Example 3:

[0021] 7.68 g of Al(NO3)3·9H2O, 6.32 g of CO(NH2)2was dissolved in 80 mL of deionized water, and then 10 g of ZnO particles were added, stirred at room temperature for 30 min, and then transferred to a 100 mL hydrothermal kettle with a polytetrafluoroethylene liner. The reaction was carried out at 140°C for 12 h, and after washing with water and drying, ZnAlLDHs@ZnO support was obtained. 2% of platinum (platinum source was chloroplatinic acid) was loaded by ultrasonic volume impregnation, then placed for 6 h, dried at 110°C for 6 h, and then calcined at 380°C for 3 h at a rate of 3°C / min from room temperature to obtain the finished catalyst.

[0022] Example 4:

[0023] 4.61 g of Al(NO3)3·9H2O, 2.48 g of CO(NH2)2, 1.07 g of Ce(NO3)3·9H2O was dissolved in 80 mL of deionized water, and then 10 g of ZnO particles were added, stirred at 50°C for 30 min, and then transferred to a 100 mL hydrothermal kettle with a polytetrafluoroethylene liner. The remaining steps were consistent with Example 3, and a Pt / CeZnAlLDHs@ZnO catalyst was obtained, with a noble metal Pt loading of 1.8%.

[0024] Example 5:

[0025] 4.65 g of Al(NO3)3·9H2O, 2.51 g of CO(NH2)2, 3.03 g of La(NO3)3·6H2O was dissolved in 80 mL of deionized water, and then 10 g of ZnO particles were added, stirred at 50°C for 30 min, and then transferred to a 100 mL hydrothermal kettle with a polytetrafluoroethylene liner. The remaining steps were consistent with Example 3, and a Pt / CeZnAlLDHs@ZnO catalyst was obtained, with a noble metal Pt loading of 1.8%.

[0026] Example 6:

[0027] Take 4.61 g Al (NO3) 3·9H2O, 2.48 g CO (NH2) 2, 3.02 g La (NO3) 3·6H2O, dissolved in 80 mL deionized water, then add 10 g ZnO particles, stir at 50℃ for 30 min, then transfer to a 100 mL hydrothermal kettle with polytetrafluoroethylene liner, react at 140℃ for 12 h, wash with water and dry to obtain LaZnAl LDHs@ZnO carrier. According to the platinum loading (platinum source is chloroplatinic acid) of 1.8% and the ruthenium loading (ruthenium source is ruthenium chloride) of 0.3%, ultrasonic equal volume impregnation is carried out, then stand for 6 h, 110℃ drying for 6 h, 3℃ / min from room temperature to 380℃, calcination for 3 h to obtain the finished catalyst. Figure 1 For example 6 TEM, the Pt particle size is about 2 nm, and the prepared carrier has strong and medium strong basic sites

[0028] Further, the evaluation condition setting is as follows:

[0029] Take 2 g of the catalyst and place it in a fixed bed reaction tube for hydrogen reduction, 2℃ / min to 300℃, 2Mpa reduction activation for 3h; after reducing to the reaction temperature, 10wt% furfuryl alcohol solution is introduced for reaction, the solution solvent is isopropyl alcohol, the mass space velocity of the reaction is 0.1h-1, the hydrogen pressure is 3Mpa, the reaction temperature is 160℃, and the hydrogen ester ratio is 50. The prepared catalyst has high reaction stability, and the 1,2-pentanediol also has higher yield.

[0030] Zinc oxide is used as the carrier, the hydrotalcite-like structure is in-situ synthesized by hydrothermal synthesis, the specific surface area of the carrier is increased, and the noble metal Pt is further dispersed; by adding rare earth metal elements, the basic sites on the surface of the catalyst are regulated and controlled, and the noble metal is anchored; the Pt interacts with the surface of the hydrotalcite structure, the reaction stability is improved, and the selectivity is also guaranteed to be high.

[0031] Further, the zinc oxide carrier is immersed in a mixed solution containing magnesium salt, aluminum salt and rare earth metal salt, the pH is adjusted to 8-10, and hydrothermal reaction is carried out at 80-140℃ for 6-12 hours; the obtained product is washed, dried, and then calcined at 300-600℃ for 4-6 hours to form a surface modified hydrotalcite-like composite carrier.

[0032] Further, the active component Pt is loaded by equal volume impregnation method, which specifically includes: mixing the platinum source solution and the cerium nitrate solution of the adjuvant, then uniformly dropping them onto the modified carrier, standing for 6-24 hours, drying at 60-110℃, and then calcining or hydrogen reduction at 300-400℃ for 2-4 hours to obtain a highly dispersed catalyst with Pt particle size of 2-5nm.

[0033] Further, the optimization conditions of the catalyst in the fixed bed reaction are as follows:

[0034] The reaction temperature is 150-180 DEG C, the hydrogen pressure is 2.5-3.5 MPa, the airspeed of the furfuryl alcohol solution is 0.05-0.2 h-1, and the molar ratio of hydrogen ester is 40-60; under the conditions, the conversion rate of furfuryl alcohol is greater than or equal to 95%, the selectivity of 1,2-pentanediol is greater than or equal to 85%, and the activity decreases by less than 5% after continuous operation for 100 hours. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 TEM image of example 6 of the present application;

[0036] Figure 2 CO2-TPD graph of example 6 of the present application LaZnAl LDHs@ZnO support;

[0037] Figure 3 Performance evaluation graph of example 6 of the present application;

[0038] Figure 4 Catalyst composition graph of the present application;

[0039] Figure 5 Catalyst evaluation result graph of the present application. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments.

[0041] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the present application.

[0042] REFERENCE Figures 1-5 A preparation method and application of a furfuryl alcohol hydrogenation catalyst, including the technical solutions realized:

[0043] One: using zinc oxide as a carrier, hydrothermally synthesizing an in-situ hydrotalcite structure on the surface of the carrier, adding a rare earth metal element to control the basic sites on the surface of the catalyst, and loading and dispersing the active component well, so that the reaction stability is improved and the selectivity is also highly guaranteed.

[0044] Two: high dispersion of Pt particles increases the active center, lower load to obtain higher conversion rate; surface modified hydrotalcite structure, its basic sites attract furfuryl alcohol, make its C-O bond break, the proportion of 1,2-pentanediol generated is improved; the catalyst is reacted in a fixed bed, and the stability is steadily improved

[0045] Three: the carrier used is basic oxide such as zinc oxide and magnesium oxide, aluminum salt, magnesium salt is nitrate and hydrochloride, platinum source chemical reagent, ruthenium salt reagent is ruthenium chloride hydrate, and the auxiliary agent is cerium nitrate compound. The mass of the active component and the auxiliary agent respectively accounts for 1-3% and 0.5-5% of the mass of the catalyst.

[0046] Comparative Example 1:

[0047] Take 5g Al 2O3 carrier, load 2% of metal platinum (platinum source is chloroplatinic acid), ultrasonic isometric impregnation, then stand for 6h, 110℃ drying for 6h, 3℃ / min from room temperature to 380℃, calcination for 3h to obtain the catalyst.

[0048] Comparative Example 2:

[0049] Under the same preparation conditions as Comparative Example 1, replace the ZnO carrier with Al 2O3 carrier, and the rest of the steps are exactly the same as Comparative Example 1, to prepare Pt / Al 2O3-ZnO catalyst for performance comparison.

[0050] Example 1:

[0051] 5.03g Mg(NO3)2·9H2O, 5.94g CO(NH2)2 is dissolved in 80mL deionized water, then 10g Al 2O3 particles are added, stirred at room temperature for 30min, then transferred to a 100mL hydrothermal kettle with polytetrafluoroethylene lining, reacted at 130℃ for 12h, washed with water and dried to obtain MgAlLDHs@Al 2O3 carrier. Take 5g carrier, load 2% of metal platinum (platinum source is chloroplatinic acid), ultrasonic isometric impregnation, then stand for 6h, 110℃ drying for 6h, 3℃ / min from room temperature to 380℃, calcination for 3h to obtain the catalyst.

[0052] Example 2:

[0053] Similar to Example 1, MgO was used as the support. 2.64 g of Al(NO3)3·9H2O, 3.76 g of CO(NH2)2was dissolved in 80 mL of deionized water, and then 10 g of MgO particles were added, stirred at room temperature for 30 min, and then transferred to a 100 mL autoclave with a polytetrafluoroethylene liner. The reaction was carried out at 130°C for 12 h, and after washing with water and drying, MgAlLDHs@MgO support was obtained. 5 g of the support was taken, and 2% of platinum (platinum source was chloroplatinic acid) was loaded by ultrasonic volume impregnation, then placed for 6 h, dried at 110°C for 6 h, and then calcined at 380°C for 3 h at a rate of 3°C / min from room temperature to obtain the catalyst.

[0054] Example 3:

[0055] 7.68 g of Al(NO3)3·9H2O, 6.32 g of CO(NH2)2was dissolved in 80 mL of deionized water, and then 10 g of ZnO particles were added, stirred at room temperature for 30 min, and then transferred to a 100 mL autoclave with a polytetrafluoroethylene liner. The reaction was carried out at 140°C for 12 h, and after washing with water and drying, ZnAlLDHs@ZnO support was obtained. 2% of platinum (platinum source was chloroplatinic acid) was loaded by ultrasonic volume impregnation, then placed for 6 h, dried at 110°C for 6 h, and then calcined at 380°C for 3 h at a rate of 3°C / min from room temperature to obtain the finished catalyst.

[0056] Example 4:

[0057] 4.61 g of Al(NO3)3·9H2O, 2.48 g of CO(NH2)2, 1.07 g of Ce(NO3)3·9H2O was dissolved in 80 mL of deionized water, and then 10 g of ZnO particles were added, stirred at 50°C for 30 min, and then transferred to a 100 mL autoclave with a polytetrafluoroethylene liner. The remaining steps were consistent with Example 3, and Pt / CeZnAlLDHs@ZnO catalyst was obtained, with a noble metal Pt loading of 1.8%.

[0058] Example 5:

[0059] 4.65 g of Al(NO3)3·9H2O, 2.51 g of CO(NH2)2, 3.03 g of La(NO3)3·6H2O was dissolved in 80 mL of deionized water, and then 10 g of ZnO particles were added, stirred at 50°C for 30 min, and then transferred to a 100 mL autoclave with a polytetrafluoroethylene liner. The remaining steps were consistent with Example 3, and Pt / CeZnAlLDHs@ZnO catalyst was obtained, with a noble metal Pt loading of 1.8%.

[0060] Example 6:

[0061] Take 4.61 g Al (NO3) 3·9H2O, 2.48 g CO (NH2) 2, 3.02 g La (NO3) 3·6H2O, dissolved in 80 mL deionized water, then add 10 g ZnO particles, stir at 50℃ for 30 min, then transfer to a 100 mL hydrothermal kettle with polytetrafluoroethylene liner, react at 140℃ for 12 h, wash with water and dry to obtain LaZnAlLDHs@ZnO carrier. According to the loading amount of platinum (platinum source is chloroplatinic acid) is 1.8%, the loading amount of ruthenium (ruthenium source is ruthenium chloride) is 0.3%, after ultrasonic equal volume impregnation, stand for 6 h, 110℃ drying for 6 h, with 3℃ / min from room temperature to 380℃, calcine for 3 h to obtain the finished catalyst. Figure 1 For example 6 TEM, Pt particle size is about 2 nm, the prepared carrier has strong and strong basic sites

[0062] Further, the evaluation conditions are set as follows:

[0063] Take 2 g of catalyst and place it in a fixed bed reaction tube for hydrogen reduction, increase the temperature to 300℃ at 2℃ / min, and reduce and activate for 3 h under the condition of 2Mpa; After reducing to the reaction temperature, 10wt% furfuryl alcohol solution is introduced for reaction, and the solution solvent is isopropyl alcohol. The mass space velocity of the reaction is 0.1h-1, the hydrogen pressure is 3Mpa, the reaction temperature is 160℃, and the hydrogen ester ratio is 50. The specific evaluation results of the catalyst are shown in the table below. The prepared catalyst has high reaction stability, and 1,2-pentanediol also has higher yield.

[0064] Zinc oxide is used as a carrier, a hydrotalcite-like structure is synthesized in situ by hydrothermal synthesis, the specific surface area of the carrier is increased, and the noble metal Pt is further dispersed; by adding rare earth metal elements, the basic sites on the surface of the catalyst are adjusted, and the noble metal is anchored; the Pt interacts with the surface of the hydrotalcite structure, the reaction stability is improved, and the selectivity is also guaranteed to be relatively high.

[0065] Further, the zinc oxide carrier is immersed in a mixed solution containing magnesium salt, aluminum salt and rare earth metal salt, the pH is adjusted to 8-10, and the hydrothermal reaction is carried out at 80-140℃ for 6-12 hours; the obtained product is washed, dried, and calcined at 300-600℃ for 4-6 hours to form a surface modified hydrotalcite-like composite carrier.

[0066] Further, the active component Pt is loaded by equal volume impregnation method, which specifically includes: mixing the platinum source solution and the cerium nitrate solution of the additive, then uniformly dropping them onto the modified carrier, standing for 6-24 hours, drying at 60-110℃, and then calcining or hydrogen reducing at 300-400℃ for 2-4 hours to obtain a highly dispersed catalyst with Pt particle size of 2-5nm.

[0067] Further, the optimization conditions of the catalyst in the fixed bed reaction are as follows:

[0068] The reaction temperature is 150-180℃, the hydrogen pressure is 2.5-3.5MPa, the air speed of the furfuryl alcohol solution is 0.05-0.2h-1, and the molar ratio of hydrogen to ester is 40-60; under the above conditions, the conversion rate of furfuryl alcohol is ≥95%, the selectivity of 1,2-pentanediol is ≥85%, and the activity decreases by less than 5% after continuous operation for 100 hours.

[0069] The above merely describes the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can make equivalent replacements or changes within the technical scope disclosed by the present application and according to the technical solutions and the inventive concept of the present application, which should be covered within the protection scope of the present application.

Claims

1. A method for the preparation and use of a catalyst for the hydrogenation of furfuryl alcohol, characterized in that, Technical solutions include implementation: I: Using zinc oxide as a carrier, in-situ hydrothermal synthesis of hydrotalcite structure on the surface of the carrier, by adding rare earth metal elements, regulating the basic sites on the surface of the catalyst, the active component has good dispersion, the reaction stability is improved, and the selectivity is also guaranteed; II: High dispersion of Pt particles increases the active center, and high conversion rate is obtained with low loading; the surface modified hydrotalcite structure attracts furfuryl alcohol through its basic sites, breaks the C-O bond, and increases the proportion of 1,2-pentanediol generated; the catalyst is used in a fixed bed, and the stability is steadily improved; III: The carrier used is zinc oxide, basic oxides such as magnesium oxide, aluminum salt, magnesium salt is nitrate and hydrochloride, platinum source chemical reagent, ruthenium salt reagent is ruthenium chloride hydrate, in addition to the auxiliary agent is cerium nitrate compound, the mass of active component and auxiliary agent respectively accounts for 1-3% and 0.5-5% of the mass of catalyst.

2. A process for the preparation of a catalyst for the hydrogenation of furfuryl alcohol and its use according to claim 1, characterized in that, Evaluation condition setting: Take 2 g catalyst is placed in fixed bed reaction tube reduction, 2 ℃ / min to 300 ℃, 2Mpa conditions reduction activation 3h;Drop to the reaction temperature and into 10wt%furfuryl alcohol solution reaction, solution solvent is isopropyl alcohol, the mass space velocity of reaction is 0.1h -1 , hydrogen pressure 3Mpa, reaction temperature 160℃, hydrogen ester ratio is 50, the prepared catalyst has higher reaction stability, 1,2-pentanediol also has higher yield.

3. A process for the preparation of a catalyst for the hydrogenation of furfuryl alcohol and its use according to claim 1, characterized in that, The zinc oxide carrier is immersed in a mixed solution containing magnesium salt, aluminum salt and rare earth metal salt, the pH is adjusted to 8-10, and the hydrothermal reaction is carried out at 80-140℃ for 6-12 hours; the obtained product is washed, dried and calcined at 300-600℃ for 4-6 hours to form a surface modified hydrotalcite composite carrier.

4. A process for the preparation of a catalyst for the hydro genation of furfuryl alcohol according to any one of claims 1 to 3, characterized in that, The loading of active component Pt uses equal volume impregnation method, which specifically includes: mixing platinum source solution and auxiliary agent cerium nitrate solution, then uniformly dropping onto the modified carrier, standing for 6-24 hours, drying at 60-110℃, then calcining or hydrogen reduction at 300-400℃ for 2-4 hours to obtain high dispersion catalyst with Pt particle size of 2-5nm.

5. The method for preparing and using a catalyst for the hydrogenation of furfuryl alcohol according to claim 1, wherein, The optimization conditions of the catalyst in the fixed bed reaction are: Reaction temperature 150-180℃, hydrogen pressure 2.5-3.5MPa, furfuryl alcohol solution space velocity 0.05-0.2h-1, hydrogen ester molar ratio 40-60; under these conditions, the conversion rate of furfuryl alcohol is ≥95%, the selectivity of 1,2-pentanediol is ≥85%, and the activity decreases by less than 5% after continuous operation for 100 hours.

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