Sulfonic acid-functionalized zirconium carbon coordination catalyst, preparation method and application in synthesis of furfuryl diether liquid fuel

Abstract

The application discloses a sulfonic acid functionalized zirconium carbon coordination catalyst, which is prepared from zirconium ions and sulfonic acid functionalized organic carbon ligands through a solvothermal self-assembly method, and simultaneously contains Lewis acid-base sites and acid sites. By changing the use amount of the zirconium ions and the sulfonic acid functionalized carbon ligands, the density, strength and acid site proportion of total acid-base sites of the catalyst can be adjusted, and then the reaction path of one-pot reduction etherification of 5-hydroxymethylfurfural can be controlled, so that the efficient synthesis of various furan-based diether liquid fuels in different alcohol endogenous hydrogen systems can be realized. Moreover, the catalyst can also efficiently catalyze the conversion of furfural, 5-methylfurfural, benzaldehyde, levulinic acid and levulinic acid ester into corresponding high-value-added products, and exhibits good catalytic universality.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of biomass energy and chemical industry, and particularly relates to a sulfonic acid functionalized zirconium-carbon coordination catalyst, a preparation method and application thereof in synthesis of furan-based diether liquid fuel. BACKGROUND

[0002] It is well known that biomass is the most abundant renewable carbon resource in nature, and its conversion into high-grade bio-based liquid fuel is an important way to achieve the carbon peak and carbon neutralization target. Among various bio-based liquid fuels, 2,5-dialkyloxymethylfuran, which is prepared from 5-hydroxymethylfurfural through reduction and etherification, is a kind of furan-based diether liquid fuel, and has the advantages of high energy density, high cetane number, high boiling point, high stability and water insolubility, etc., fully meeting the use requirements of diesel engine, and can be used in mixture with commercial diesel or alone, thus having a very broad application prospect.

[0003] At present, the catalytic preparation system of 2,5-dialkyloxymethylfuran can be divided into two categories: exogenous hydrogen system and endogenous hydrogen system. The exogenous hydrogen system uses hydrogen as hydrogen source, and needs metal hydrogenation catalyst and acid dehydration etherification catalyst. Due to the great hidden danger in the production, transportation and use of hydrogen, and the difficulty for metal hydrogenation catalyst and acid dehydration etherification catalyst to exert their respective optimal catalytic activity in the same system, the reaction efficiency and product yield are not ideal, thus the practical application of the exogenous hydrogen system is greatly limited. In comparison, the endogenous hydrogen system uses low-carbon alcohol as hydrogen donor, and realizes the synthesis of 2,5-dialkyloxymethylfuran through coupling MPV reduction reaction and dehydration etherification reaction, and has received extensive attention in recent years. It is particularly pointed out that in the endogenous hydrogen system, the MPV reduction reaction and the dehydration etherification reaction are respectively catalyzed by Lewis acid-base sites and Br nsted acid sites, and the two reactions are not independent, but are coupled together, thus the reaction efficiency and product yield are greatly improved. The acid sites are catalytic, therefore, it is extremely important to design an efficient acid-base bifunctional catalyst for the preparation of 2,5-dialkyloxymethyl furan from 5-hydroxymethylfurfural through one-pot reductive etherification. Although many catalysts such as Sn-BEA (ChemCatChem, 2014, 6: 508-513), Hf-BEA (ChemSusChem, 2014, 7: 2255-2265), Zr-SBA-UH (Energy Technology, 2019, 7: 1801071), ZrCP@USY (Journal of Catalysis, 2020, 389: 87-98), Zr-S-F (ACS Sustainable Chemistry & Engineering, 2022, 10: 4969-4979) and Cu / ZrO2 (ACS Catalysis, 2022, 12: 7357-7367) have been designed, but they only work in secondary alcohols (isopropyl alcohol and sec-butyl alcohol) and have poor effects in more inexpensive primary alcohols (such as ethanol, propanol and n-butanol) (the yield of target product is usually less than 65%). Therefore, it is still necessary to develop an acid-base bifunctional catalyst with higher activity and higher universality.

[0004] The first object of the present application provides:

[0005] The sulfonic acid functionalized zirconium carbon coordination catalyst is prepared by using organic carbon as a carrier, and the carboxyl and phenolic hydroxyl groups on the surface of the organic carbon are combined with Zr through coordination bonds. 4+ The surface of the organic carbon also contains sulfonic acid groups.

[0006] The second object of the present application provides:

[0007] The preparation method of the sulfonic acid functionalized zirconium carbon coordination catalyst comprises the following steps:

[0008] The zirconium salt and the sulfonic acid functionalized organic carbon are added to an organic solvent respectively and stirred uniformly; the organic solvent containing the zirconium salt is slowly added dropwise into the organic solvent containing the sulfonic acid functionalized organic carbon, and stirred uniformly.

[0009] The mixed solution is moved into a reaction kettle for standing reaction; after the reaction is completed, the sol-like solid product is separated out and washed and dried to obtain the catalyst.

[0010] The organic solvent is selected from amide solvents.

[0011] The zirconium salt is one of zirconium oxychloride, zirconium tetrachloride or zirconium nitrate, and preferably zirconium tetrachloride.

[0012] The preparation method of the sulfonic acid functionalized organic carbon comprises the following steps: uniformly mixing a saccharide compound and a sulfonating agent, grinding, and then moving into a reaction kettle for carbonization after standing; after the reaction is completed, the black solid is washed, dried, and ground to obtain the sulfonic acid functionalized organic carbon.

[0013] The sulfonating agent is one of p-toluenesulfonic acid, p-aminobenzenesulfonic acid, or p-sulfobenzoic acid, and preferably is p-toluenesulfonic acid; and the saccharide compound is selected from monosaccharide, oligosaccharide, or polysaccharide.

[0014] The carbonization temperature is 160-200 DEG C, and preferably is 180 DEG C; and the carbonization time is 12-36 h, and preferably is 24 h.

[0015] The concentration of the zirconium salt in the organic solvent is 20-50 g / L; the mass ratio of the zirconium salt to the sulfonic acid functionalized organic carbon ligand is 0.5:1-2:1; the reaction temperature is 100-160 DEG C; and the reaction time is 12-36 h.

[0016] The third object of the present application provides:

[0017] The sulfonic acid functionalized zirconium carbon coordination catalyst is applied in the catalytic synthesis of furan-based diether compounds.

[0018] The furan-based diether compound is selected from 2,5-dialkoxy methyl furan, and low-carbon alcohol is used as endogenous hydrogen, and 5-hydroxymethyl furfural is used as a substrate.

[0019] The number of carbon atoms in the low-carbon alcohol is not more than 5.

[0020] The application comprises the following steps:

[0021] The sulfonic acid functionalized zirconium carbon coordination catalyst, low-carbon alcohol, and 5-hydroxymethyl furfural are added into a high-pressure reaction kettle, the kettle is sealed and the air in the kettle is replaced with nitrogen; the kettle is stirred and heated to a specified temperature, and after a certain reaction time, 5-hydroxymethyl furfural is converted into 2,5-dialkoxy methyl furan through a one-pot reduction etherification reaction with 2,5-dihydroxymethyl furan as an intermediate product; the low-carbon alcohol is one of ethanol, n-propanol, isopropanol, n-butanol, or sec-butanol; the amount of 5-hydroxymethyl furfural is 1-4 wt% of the amount of low-carbon alcohol; the amount of the sulfonic acid functionalized zirconium carbon coordination catalyst is 10-50 wt% of the amount of 5-hydroxymethyl furfural; the reaction temperature is 80-200 DEG C; and the reaction time is 1-8 h.

[0022] The fourth object of the present application provides:

[0023] A method for regulating the selectivity of catalytic synthesis of 5-hydroxymethylfurfural product, said product including 2,5-dialkoxy methyl furan and 2,5-dihydroxymethyl furan;

[0024] Low carbon alcohol is used as endogenous hydrogen in the catalytic synthesis, and 5-hydroxymethylfurfural is used as substrate;

[0025] In the method, by The ratio of acidic sites is 6.5-7.5, so that the yield of 2,5-dialkoxy methyl furan is greater than the yield of 2,5-dihydroxymethyl furan in the product;

[0026] In the method, by The ratio of acidic sites is 8.5-9.5 or 5.0-6.0, so that the yield of 2,5-dialkoxy methyl furan is less than the yield of 2,5-dihydroxymethyl furan in the product.

[0027] The number of carbon atoms in the low carbon alcohol is not greater than 5.

[0028] The fifth object of the present application provides:

[0029] Application of sulfonic acid functionalized zirconium carbon coordination catalyst in selective conversion of carbonyl compounds.

[0030] The carbonyl compound is selected from furfural, 5-methylfurfural, benzaldehyde, levulinic acid and levulinic acid ester, etc.; and low carbon alcohol is used as endogenous hydrogen.

[0031] The target product of conversion is selected from 2-isopropoxy methyl furan, 5-methyl-2-isopropoxy methyl furan, benzyl alcohol, gamma-valerolactone, etc.

[0032] The amount of 5-hydroxymethylfurfural is 1-4wt% of the amount of low carbon alcohol, the amount of sulfonic acid functionalized zirconium carbon coordination catalyst is 10-50wt% of the amount of carbonyl compound, the reaction temperature is 80-200℃, and the reaction time is 1-8h. SUMMARY

[0033] The technical problem to be solved by the present application is that 5-hydroxymethylfurfural has low catalytic activity and poor universality in the process of preparing 2,5-dialkoxy methyl furan by one-pot reduction etherification reaction in the endogenous hydrogen system. The present application provides a sulfonic acid functionalized zirconium carbon coordination catalyst, which realizes efficient synthesis of corresponding 2,5-dialkoxy methyl furan in various low carbon alcohols.

[0034] Beneficial effects

[0035] 1) The present application uses zirconium as a metal ion donor and sulfonic acid functionalized organic carbon as a ligand, and Lewis acid-base sites and The sulfonic acid functionalized zirconium carbon coordination catalyst has cheap and easily available ligands, simple manufacturing process and easy scale-up synthesis. The sulfonic acid functionalized zirconium carbon coordination catalyst can make 5-hydroxymethylfurfural preferentially undergo MPV reduction reaction and then dehydration etherification reaction, thereby realizing directional preparation of 2,5-dialkoxy methyl furan. The sulfonic acid functionalized zirconium carbon coordination catalyst has excellent catalytic universality, not only exhibits good catalytic activity for primary alcohols and secondary alcohols, but also can efficiently catalyze selective conversion of various carbonyl compounds. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is the FT-IR spectrum of GC-SO3H prepared in Comparative Example 1.

[0037] Figure 2 is the FT-IR spectrum of Zr-GC-SO3H-0.5 prepared in Example 1.

[0038] Figure 3 is the Py-IR spectrum of Zr-GC-SO3H-1.0 prepared in Example 3.

[0039] Figure 4 is the GC chromatogram of preparation of 2,5-diisopropoxy methyl furan by one-pot reduction etherification of 5-hydroxymethyl furfural catalyzed by Zr-GC-SO3H-1.0 in Example 5. DETAILED DESCRIPTION

[0040] The application discloses a sulfonic acid functionalized zirconium carbon coordination catalyst, which is prepared by solvent thermal self-assembly method of zirconium ions and sulfonic acid functionalized organic carbon ligands, and simultaneously contains Lewis acid and base sites and acid sites. By changing the use amount of zirconium ions and sulfonic acid functionalized carbon ligands, the density, strength and By controlling the acid site ratio and thus the one-pot reductive etherification reaction pathway of 5-hydroxymethylfurfural, the efficient synthesis of various furanyl diether liquid fuels can be achieved in different alcohol-based endogenous hydrogen systems. Furthermore, the catalyst can efficiently catalyze the conversion of furfural, 5-methylfurfural, benzaldehyde, levulinic acid, and levulinic esters into corresponding high-value-added products, demonstrating good catalytic versatility. In addition, the alcohol-based endogenous hydrogen system used in this invention does not require additional exogenous hydrogen donors or other reaction solvents; the reaction system composition is simple, the reaction process is safe and stable, and the yield and selectivity of the target product are high, which is beneficial for subsequent separation and application.

[0041] The technical concept of this invention is to directly use sulfonic acid-functionalized organic carbon as a bifunctional ligand and zirconium as a metal ion donor to synthesize a sulfonic acid-functionalized zirconium carbon coordination catalyst with controllable acid-base site content, strength, and ratio via a solvothermal self-assembly method. The sulfonic acid-functionalized organic carbon contains abundant carboxyl groups (-COOH), phenolic hydroxyl groups (Ph-OH), and sulfonic acid groups (-SO3H). The presence of -COOH and Ph-OH allows it to replace commercially available carboxylic acids and phenolic acids as organic ligands in coordination reactions with zirconium. The Zr in the ZOC network formed by the coordination reaction... 4+ Able to provide Lewis acid sites, O 2- It can provide Lewis basic sites; the uncoordinated -SO3H can provide... Acidic sites. Meanwhile, Lewis acid-base sites are primarily responsible for MPV reduction reactions. Acidic sites are primarily responsible for dehydration and etherification reactions, and the former is more readily carried out than the latter. Therefore, at Lewis acid-base sites and With the synergistic effect of acidic sites, 5-hydroxymethylfurfural can be efficiently synthesized into 2,5-dialkoxymethylfuran through a one-pot reductive etherification process.

[0042] Compare with Example 1

[0043] Take 10g of glucose and 10g of p-benzenesulfonic acid, mix them evenly, grind them, and transfer them to a reaction vessel. Let them stand at 180℃ for 24h for carbonization. After the reaction is completed, the black solid is repeatedly washed with anhydrous ethanol and deionized water until the filtrate is clear. Place the washed black solid in a vacuum drying oven and dry it at 100℃ for 12h. After grinding and pulverizing, sulfonic acid functionalized organic carbon can be obtained, abbreviated as GC-SO3H.

[0044] FT-IR characterization analysis showed that ( Figure 1 ), 566cm -1 The stretching vibration peak at 1035 cm⁻¹ is attributed to the CS bond. -1 1192cm -1 and 1384cm -1The stretching vibration peak at 1702 cm⁻¹ is attributed to the O=S=O bond. -1 The stretching vibration peak attributable to the C=O bond is 3412 cm⁻¹. -1 The stretching vibration peaks attributed to OH bonds indicate that -COOH, Ph-OH, and -SO3H have been successfully introduced into GC-SO3H. Acidic sites. Furthermore, NH3-TPD characterization analysis revealed that GC-SO3H... The acidic site content is 2.27 mmol / g.

[0045] Next, 0.25 g of 5-hydroxymethylfurfural, 19.75 g of isopropanol, and 0.1 g of GC-SO3H were added to a 100 mL reactor. After sealing, the air in the reactor was continuously purged with nitrogen five times. The temperature was raised to 140 °C at a stirring speed of 400 rpm. After reacting for 4 h, the conversion rate of 5-hydroxymethylfurfural was 91.6%, the yield of 5-isopropoxymethylfurfural was 86.7%, and the yields of 2,5-dihydroxymethylfuran and 2,5-diisopropoxymethylfuran were both 0. This not only indicates... The acidic sites are primarily responsible for the dehydration and etherification of 5-hydroxymethylfurfural, and also indicate that the target product cannot be generated in the absence of Lewis acid-base sites.

[0046] Example 1

[0047] 1 g of zirconium tetrachloride and 2 g of GC-SO3H (prepared in Comparative Example 1) were added to 80 mL of dimethylformamide and stirred until homogeneous. The zirconium tetrachloride solution was slowly added dropwise to the sulfonic acid-functionalized organic carbon solution and stirred until homogeneous. The mixture was transferred to a reaction vessel and reacted at 120 °C for 24 h under static conditions. After the reaction was completed, the solid sol product was repeatedly washed with anhydrous ethanol and deionized water until no chloride ions were detected. The washed solid product was dried in a vacuum drying oven at 100 °C for 12 h. After grinding and pulverizing, the sulfonic acid-functionalized zirconium carbon coordination catalyst, abbreviated as Zr-GC-SO3H-0.5, was obtained.

[0048] FT-IR characterization analysis showed that ( Figure 2 Compared to GC-SO3H, Zr-GC-SO3H-0.5 has a higher concentration at 662 cm⁻¹. -1 A new diffraction peak appeared, attributed to the stretching vibration peak of the Zr-O bond, indicating that Zr-GC-SO3H-0.5 not only retains the... Acidic sites (-SO3H) were also successfully introduced, and Lewis acid-base sites (Zr) were also successfully introduced. 4+ -O 2-Meanwhile, through NH3-TPD, CO2-TPD and Py-IR characterization analysis, it can be known that the total acid site content of Zr-GC-SO3H-0.5 is 1.84 mmol / g, the basic site content is 0.96 mmol / g, The ratio of acid sites is 5.37.

[0049] Next, 0.25 g of 5-hydroxymethylfurfural, 19.75 g of isopropyl alcohol and 0.1 g of Zr-GC-SO3H-0.5 were added into a 100 mL reaction kettle, and after sealing, the air in the kettle was replaced with nitrogen for 5 times; under the stirring speed of 400 rpm, the temperature was raised to 140 ℃, and after 4 h of reaction, the conversion rate of 5-hydroxymethylfurfural was 93.5%, the yield of 5-isopropoxymethylfurfural was 3.2%, the yield of 2,5-dihydroxymethylfuran was 67.6%, and the yield of 2,5-diisopropoxymethylfuran was 3.7%; compared with the catalytic reaction results of the control example 1, it can be seen that the Lewis acid-base sites are mainly responsible for the MPV reduction reaction of 5-hydroxymethylfurfural, The acid sites are mainly responsible for the dehydration etherification reaction of 5-hydroxymethylfurfural, and it is shown that the target product can be successfully generated under the synergistic action of the Lewis acid-base sites and the acid sites.

[0050] Example 2

[0051] 3 g of zirconium tetrachloride and 2 g of GC-SO3H (prepared in the control example 1) were respectively added into 80 mL of dimethylformamide and stirred uniformly; the zirconium tetrachloride solution was slowly added into the sulfonic acid functionalized organic carbon solution and stirred uniformly; the mixed solution was moved into a reaction kettle, and under the stationary condition, 120 ℃ was reacted for 24 h; after the reaction was completed, the solid sol-like product was repeatedly washed with anhydrous ethanol and deionized water until no chloride ion was detected; the washed solid product was placed in a vacuum drying box for drying, 100 ℃ was dried for 12 h, and after grinding and crushing, a sulfonic acid functionalized zirconium carbon coordination catalyst, which was simply written as Zr-GC-SO3H-1.5, was obtained.

[0052] Through FT-IR characterization analysis, compared with GC-SO3H, Zr-GC-SO3H-1.5 not only retains the acid site (-SO3H), but also successfully introduces the Lewis acid-base site (Zr 4+ -O 2- ). Meanwhile, through NH3-TPD, CO2-TPD and Py-IR characterization analysis, it can be known that the total acid site content of Zr-GC-SO3H-1.5 is 2.34 mmol / g, the basic site content is 1.67 mmol / g, The ratio of acid sites is 8.81.

[0053] Next, 0.25 g of 5-hydroxymethylfurfural, 19.75 g of isopropyl alcohol and 0.1 g of Zr-GC-SO3H-1.5 were added into a 100 mL reaction kettle, and after sealing, the air in the kettle was replaced with nitrogen for 5 times continuously; under the stirring speed of 400 rpm, the temperature was raised to 140°C, and after 4 h of reaction, the conversion rate of 5-hydroxymethylfurfural was 98.7%, the yield of 5-isopropoxymethylfurfural was 1.1%, the yield of 2,5-dihydroxymethylfuran was 81.5%, and the yield of 2,5-diisopropoxymethylfuran was 1.9%, which not only indicated that the Lewis acid-base site was mainly responsible for the MPV reduction reaction of 5-hydroxymethylfurfural, the acidic site was mainly responsible for the dehydration etherification reaction of 5-hydroxymethylfurfural, and it was also indicated that the target product could be successfully generated under the synergistic action of the Lewis acid-base site and the acidic site, and it was also indicated that the content of the Lewis acid-base site and the acidic site would significantly affect the MPV reduction reaction and the dehydration etherification reaction of 5-hydroxymethylfurfural, and the yield of the intermediate product and the target product.

[0054] Example 3

[0055] 2 g of zirconium tetrachloride and 2 g of GC-SO3H (prepared in the comparative example 1) were respectively added into 80 mL of dimethylformamide and stirred uniformly; the zirconium tetrachloride solution was slowly added into the sulfonic acid functionalized organic carbon solution and stirred uniformly; the mixed solution was moved into a reaction kettle, and under the stationary condition, 120°C was reacted for 24 h; after the reaction was completed, the solid sol-like product was repeatedly washed with anhydrous ethanol and deionized water until no chloride ion was detected; the washed solid product was placed in a vacuum drying box for drying, 100°C was dried for 12 h, and after grinding and crushing, the sulfonic acid functionalized zirconium carbon coordination catalyst, which was simply written as Zr-GC-SO3H-1.0, was obtained.

[0056] Through the FT-IR characterization analysis, compared with GC-SO3H, Zr-GC-SO3H-1.0 not only retained the acidic site (-SO3H), but also successfully introduced the Lewis acid-base site (Zr 4+ -O 2- ). At the same time, through the NH3-TPD, CO2-TPD and Py-IR characterization analysis, the total acidic site content of Zr-GC-SO3H-1.0 was 2.08 mmol / g, the basic site content was 1.39 mmol / g, the acidic site ratio was 7.12.

[0057] Next, 0.25 g of 5-hydroxymethylfurfural, 19.75 g of isopropyl alcohol and 0.1 g of Zr-GC-SO3H-1.0 were added into a 100 mL reaction kettle, and after sealing, the air in the kettle was continuously replaced with nitrogen for 5 times; under the stirring speed of 400 rpm, the temperature was raised to 140°C, and after 4 h of reaction, the conversion rate of 5-hydroxymethylfurfural was 94.9%, the yield of 5-isopropoxymethylfurfural was 2.6%, the yield of 2,5-dihydroxymethylfuran was 10.8%, and the yield of 2,5-diisopropoxymethylfuran was 38.2%, which indicated that the moderate The proportion of acidic sites Figure 3 ) is beneficial to balance the MPV reduction reaction performance and the dehydration etherification reaction performance of the catalyst, so that they are synergistically carried out, and thus the efficient synthesis of 2,5-diisopropoxymethylfuran is greatly promoted.

[0058] Example 4

[0059] In a 100 mL reaction kettle, 0.25 g of 5-hydroxymethylfurfural, 19.75 g of isopropyl alcohol and 0.1 g of Zr-GC-SO3H-1.0 were added, and after sealing, the air in the kettle was continuously replaced with nitrogen for 5 times; under the stirring speed of 400 rpm, the temperature was raised to 180°C, and after 4 h of reaction, the conversion rate of 5-hydroxymethylfurfural was 100.0%, and the yield of 2,5-diisopropoxymethylfuran was 88.4%, which indicated that increasing the reaction temperature and prolonging the reaction time were beneficial to further improve the catalytic activity of the catalyst and promote the formation of the target product.

[0060] Example 5

[0061] In a 100 mL reaction kettle, 0.25 g of 5-hydroxymethylfurfural, 19.75 g of isopropyl alcohol and 0.1 g of Zr-GC-SO3H-1.0 were added, and after sealing, the air in the kettle was continuously replaced with nitrogen for 5 times; under the stirring speed of 400 rpm, the temperature was raised to 180°C, and after 6 h of reaction, the conversion rate of 5-hydroxymethylfurfural was 100.0%, and the yield of 2,5-diisopropoxymethylfuran was 95.8% Figure 4 ).

[0062] Examples 6-9

[0063] To verify the reaction path of Zr-GC-SO3H-1.0 catalyzing the one-pot reductive etherification of 5-hydroxymethylfurfural to prepare 2,5-diisopropoxymethylfuran, the present application also comparatively studied the product distribution under other reaction temperatures, and the reaction conditions were the same as those in Example 5 except for the reaction temperature and reaction time. The specific results are shown in Table 1. As can be seen from Table 1, when the reaction temperature is lower than 100℃, 5-isopropoxymethylfurfural is not formed, and the main product is 2,5-dihydroxymethylfuran. However, when the reaction temperature is increased to 120℃, 5-isopropoxymethylfurfural begins to form, which indicates that under the catalysis of Zr-GC-SO3H-1.0, the formation of 5-isopropoxymethylfurfural is more difficult than that of 2,5-dihydroxymethylfuran, i.e. the MPV reduction reaction of 5-hydroxymethylfurfural is easier to proceed than the dehydration etherification reaction. In other words, the main pathway for the formation of 2,5-diisopropoxymethylfuran is that 5-hydroxymethylfurfural first undergoes MPV reduction reaction to generate 2,5-dihydroxymethylfuran, and then 2,5-dihydroxymethylfuran undergoes dehydration etherification reaction.

[0064] Table 1

[0065]

[0066] Example 10

[0067] In a 100 mL reaction kettle, 0.25 g of 5-hydroxymethylfurfural, 19.75 g of ethanol and 0.1 g of Zr-GC-SO3H-1.0 were added, and after sealing, the air in the kettle was continuously replaced with nitrogen for 5 times; under the stirring speed of 400 rpm, the temperature was increased to 180℃, and after 6 h of reaction, the conversion rate of 5-hydroxymethylfurfural was 99.2%, and the yield of 2,5-diethoxymethylfuran was 93.2%.

[0068] Example 11

[0069] In a 100 mL reaction kettle, 0.25 g of 5-hydroxymethylfurfural, 19.75 g of propyl alcohol and 0.1 g of Zr-GC-SO3H-1.0 were added, and after sealing, the air in the kettle was continuously replaced with nitrogen for 5 times; under the stirring speed of 400 rpm, the temperature was increased to 180℃, and after 6 h of reaction, the conversion rate of 5-hydroxymethylfurfural was 93.5%, and the yield of 2,5-dipropoxymethylfuran was 85.4%.

[0070] Example 12

[0071] 0.25 g of 5-hydroxymethylfurfural, 19.75 g of butanol, and 0.1 g of Zr-GC-SO3H-1.0 were added to a 100 mL reactor. After sealing, the air in the reactor was continuously purged with nitrogen five times. The temperature was raised to 180 °C at a stirring speed of 400 rpm. After reacting for 6 h, the conversion rate of 5-hydroxymethylfurfural was 97.7%, and the yield of 2,5-dibutoxymethylfuran was 90.7%.

[0072] Example 13

[0073] 0.25 g of 5-hydroxymethylfurfural, 19.75 g of sec-butanol, and 0.1 g of Zr-GC-SO3H-1.0 were added to a 100 mL reactor. After sealing, the air in the reactor was continuously purged with nitrogen five times. The temperature was raised to 180 °C at a stirring speed of 400 rpm. After reacting for 6 h, the conversion rate of 5-hydroxymethylfurfural was 100.0%, and the yield of 2,5-disec-butoxymethylfuran was 94.6%.

[0074] To better highlight the good versatility of the sulfonic acid functionalized zirconium carbon coordination catalyst prepared in this invention, the catalytic performance of Zr-GC-SO3H-1.0 prepared in Example 4 was compared with that of other catalysts. The specific results are shown in Table 2. The catalytic reaction conditions were adjusted accordingly to suit the applicability of each catalyst. As can be seen from Table 2, the sulfonic acid functionalized zirconium carbon coordination catalyst of this invention exhibits good catalytic performance due to its Zr content. 4+ Able to provide Lewis acid sites, O 2- It can provide Lewis basic sites, and -SO3H can provide... Acidic sites and moderate The synergistic effect between the proportions of acidic sites enables the catalyst to catalyze the MPV reduction of 5-hydroxymethylfurfural followed by dehydration and etherification, significantly reducing side reactions such as acetal formation and greatly increasing the directionality of the 5-hydroxymethylfurfural reaction, thereby improving the yields of various 2,5-dialkoxymethylfurans. Particularly noteworthy is that the catalyst in this patent achieves yields of over 85% for all target products in the catalytic conversion of primary alcohols to 2,5-dialkoxymethylfurans, while other catalysts in the prior art achieve conversion rates not exceeding 65%.

[0075] Table 2

[0076]

[0077] Examples 14-21

[0078] The following examples are the catalytic effects of Zr-GC-SO3H-1.0 prepared in the above-mentioned Example 4 on the selective conversion of other carbonyl compounds such as furfural, 5-methylfurfural, benzaldehyde, levulinic acid and levulinic acid ester, etc. The specific results are shown in Table 3. As can be seen from Table 3, in addition to being able to catalyze the conversion of 5-hydroxymethylfurfural to various 2,5-dialkyloxymethylfuran, Zr-GC-SO3H-1.0 can also efficiently catalyze the conversion of carbonyl compounds such as furfural, 5-methylfurfural, benzaldehyde, levulinic acid and levulinic acid ester, etc. to the corresponding high value-added products, which further demonstrates that Zr-GC-SO3H-1.0 has excellent catalytic activity and catalytic universality.

[0079] Table 3

[0080]

[0081] Reference:

[0082] [1]ACS Catalysis,2022,12:7357-7367.

[0083] [2]ChemCatChem,2014,6:508-513.

[0084] [3]Catalysis Letters,2017,147:345-359.

[0085] [4]Catalysis Science and Technology,2018,8:4474-4484.

Claims

1. A method of modulating the selectivity of the catalytic synthesis product of 5- hydroxymethylfurfural, characterized in that, The product includes 2,5-dialkoxy methyl furan and 2,5-dihydroxymethyl furan; Low carbon alcohol is used as endogenous hydrogen and 5-hydroxymethyl furfural is used as substrate in the catalytic synthesis; In the method, the Lewis / Brønsted acid site ratio of the sulfonic acid functionalized zirconium carbon coordination catalyst is 6.5-7.5, so that the yield of 2,5-dialkoxy methyl furan is greater than the yield of 2,5-dihydroxymethyl furan in the product; In the method, the Lewis / Brønsted acid site ratio of the sulfonic acid functionalized zirconium carbon coordination catalyst is 8.5-9.5 or 5.0-6.0, so that the yield of 2,5-dialkoxy methyl furan is less than the yield of 2,5-dihydroxymethyl furan in the product; The sulfonic acid functionalized zirconium carbon coordination catalyst is prepared by using organic carbon as a carrier, and carboxyl and phenolic hydroxyl groups on the surface of the organic carbon are combined with Zr through coordination bonds 4+ , and the surface of the organic carbon also contains sulfonic acid groups. The preparation method of the sulfonic acid functionalized zirconium carbon coordination catalyst comprises the following steps: The zirconium salt and the sulfonic acid functionalized organic carbon are respectively added to an organic solvent and stirred uniformly; the organic solvent containing the zirconium salt is slowly added dropwise into the organic solvent containing the sulfonic acid functionalized organic carbon and stirred uniformly; The mixed solution is moved into a reaction kettle for standing reaction; after the reaction is completed, a sol-like solid product is separated out and washed and dried, so that the catalyst is obtained; The organic solvent is selected from amide solvents; The zirconium salt is one of zirconium oxychloride, zirconium tetrachloride or zirconium nitrate; The preparation method of the sulfonic acid functionalized organic carbon comprises the following steps: the saccharide compound and the sulfonation reagent are mixed uniformly, grinded, moved into a reaction kettle for carbonization standing, and after the reaction is completed, the black solid is washed, dried and grinded, so that the sulfonic acid functionalized organic carbon is obtained; The sulfonation reagent is p-toluenesulfonic acid; and the saccharide compound is selected from monosaccharides, oligosaccharides or polysaccharides.

2. The method of claim 1, wherein the method is characterized by, The carbonization temperature is 160-200 DEG C; and the carbonization time is 12-36 h; The concentration of the zirconium salt in the organic solvent is 20-50 g / L; and the mass ratio of the zirconium salt to the sulfonic acid functionalized organic carbon is 0.5:1-2:1; The standing reaction temperature is 100-160 DEG C; and the standing reaction time is 12-36 h.

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