CN114315553A - Method for preparing levulinic acid by catalyzing glucose in hydrophilic DES (data encryption Standard) by solid acid - Google Patents
Method for preparing levulinic acid by catalyzing glucose in hydrophilic DES (data encryption Standard) by solid acid Download PDFInfo
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Abstract
The invention provides a method for preparing levulinic acid by catalyzing glucose in hydrophilic DES (data encryption standard) by solid acid, belonging to the field of new energy and new materials. According to the invention, MOFs material is used as a carrier, a composite solid acid catalyst with Bronsted acidity and Lewis acidity is obtained by loading phosphotungstic acid based on a solvothermal method, dehydration reaction of glucose is catalyzed in a hydrophilic eutectic solvent DES, levulinic acid is prepared, and 5-HMF can be obtained at the same time. The solid acid catalyst of the invention shows better stability in recycling use, and the yield of the levulinic acid still reaches 34 percent after the solid acid catalyst is repeatedly used for five times. The invention provides a novel catalytic process for converting carbohydrates into high-value-added bio-based chemicals, which is green, cheap, efficient and stable.
Description
Technical Field
The invention belongs to the field of new energy and new materials, relates to a method for preparing bio-based chemicals by biomass conversion, and particularly relates to a method for preparing 5-HMF and levulinic acid by catalyzing glucose in hydrophilic DES by solid acid.
Background
In recent years, the use of traditional fossil fuels in large quantities has not only led to the rapid decline of their reserves, but also increased concerns about environmental pollution and carbon emissions, and thus the search for new energy sources that are environmentally friendly and sustainable is urgent. The biomass is a renewable raw material with wide source and easily obtained raw materials, has the characteristics of sustainability, biodegradability and the like, and is a clean resource with great application prospect. Among them, various processes for producing platform chemicals from lignocellulosic biomass-derived carbohydrates have drawn attention, but levulinic acid and pentahydroxymethylfurfural can be used as platform compounds, and have a wide industrial application value.
Levulinic acid is an important chemical intermediate, and various derivatives of the levulinic acid can be used in a plurality of fields such as fuels, medicines, multifunctional materials and the like, and are evaluated as one of 12 bio-based platform chemicals by the U.S. department of energy. The production and synthesis methods of levulinic acid can be divided into two main categories according to different synthesis raw materials: 1) catalytic hydrolysis of furfuryl alcohol; 2) and (3) biomass hydrolysis. The furfuryl alcohol hydrolysis method, as the name suggests, takes furfuryl alcohol as raw material to synthesize levulinic acid under the action of acid catalysis. The biomass hydrolysis method is to prepare the levulinic acid by heating and hydrolyzing biomass resources containing cellulose or starch and the like serving as raw materials under an acidic condition. The greatest difference between the two technical processes is the difference between the raw materials, and furfuryl alcohol can also be obtained by catalytic hydrolytic conversion of biomass. The furfuryl alcohol method requires four steps, while the biomass hydrolysis method can obtain levulinic acid by only two steps, has the obvious advantages of simple process, low cost, wide raw material source and the like, and is a main method for producing levulinic acid, and 5-hydroxymethylfurfural is used as a direct precursor of the levulinic acid and can also be prepared in the biomass hydrolysis method. In one aspect, homogeneous acid catalysts are commonly used in the hydrolysis of biomass to produce levulinic acid and 5-hydroxymethylfurfural, wherein H2SO4HCl and AlCl3The catalyst is the most widely and effectively applied catalyst, however, the single homogeneous catalyst often has the problems of low catalytic conversion efficiency, serious equipment corrosion, high acid recovery cost, difficult levulinic acid purification and the like; on the other hand, reaction systems using water and other organic solvents as carriers also have many disadvantages.In order to further improve the yield of the levulinic acid, a composite catalyst which is simple to prepare, convenient to recover and small in pollution and simultaneously has Bronsted acid and Lewis acid active sites is synthesized, and a traditional solvent is replaced by hydrophilic DES with high boiling point, low volatility and high polarity to perform a catalytic conversion experiment on glucose, so that carbohydrates such as cellulose and glucose can be more fully contacted with a solid catalyst, the whole reaction path from glucose to fructose to levulinic acid is better promoted, and the conversion rate of the levulinic acid is improved.
Aiming at the characteristic of glucose conversion, the invention selects proper MOF as a carrier to load heteropoly acid, synthesizes a novel solid acid with stronger Bronsted and Lewis properties, and is used for realizing the catalytic conversion of glucose in a hydrophilic DES solvent so as to prepare 5-HMF and levulinic acid. The invention provides a preparation method of a cheap, efficient, stable, low-toxicity and recyclable solid acid catalyst, which is used for dehydration reaction of glucose.
Disclosure of Invention
Aiming at the defects of the existing preparation process, the invention provides a method for preparing 5-HMF and levulinic acid by catalyzing glucose with a multifunctional solid catalyst, which takes cheap glucose as a starting raw material and obtains the final products of 5-HMF and levulinic acid through a dehydration process catalyzed by solid acid. And introducing the hydrophilic DES into the reaction system to form a biphasic solvent system to reduce product inhibition and improve selectivity and yield of 5-HMF and levulinic acid.
In order to achieve the purpose, the invention adopts the technical scheme that:
a method for preparing levulinic acid by catalyzing glucose in hydrophilic DES by solid acid, comprising the following steps:
first, the solid acid HPW @ MIL-125(Zn) is prepared
Mixing terephthalic acid, zinc sulfate, methanol and N, N-Dimethylformamide (DMF) according to a certain volume ratio, stirring for 12-24 h at 120-150 ℃, collecting milky white precipitate, repeatedly washing with a mixed solution of DMF and anhydrous methanol, drying to obtain white MIL-125(Zn) powder, adding the white MIL-125(Zn) powder into a mixed solution of phosphotungstic heteropoly acid and acetonitrile, stirring for 60-90 min, and drying for 12-24 h at 120-150 ℃ to obtain solid acid HPW @ MIL-125 (Zn).
0.037-0.066 g of terephthalic acid, 0.021-0.037 g of zinc sulfate and 1-5 ml of methanol are correspondingly added into every 5-9 ml of N, N-dimethylformamide.
In the mixed solution of the phosphotungstic heteropoly acid and the acetonitrile, the mass-to-volume ratio of the phosphotungstic heteropoly acid to the acetonitrile is 1: 5-10, and the mass ratio of the phosphotungstic heteropoly acid to the MIL-125(Zn) is 5-25: 1.
And secondly, placing glucose and hydrophilic DES into a reaction kettle, heating at 100-150 ℃, stirring for 30-60 min until the glucose and the hydrophilic DES are dissolved, then adding HPW @ MIL-125(Zn) for dehydration reaction at 100-150 ℃, reacting for 2-7 h at a stirring speed of 300-500 r/min, and performing post-treatment after the dehydration reaction to obtain levulinic acid and 5-HMF, wherein the yield of the levulinic acid is calculated to be more than 50% by adopting high performance liquid chromatography analysis. In the dehydration reaction process, due to the introduction of the hydrophilic DES, the reaction process can be carried out in a green solvent system, the mass transfer resistance can be reduced, the contact area between a substrate and a catalyst can be increased, the yield of a target product is improved, and the pollution to the environment is reduced.
The mass ratio of the glucose to the hydrophilic DES is 1: 10-50.
The mass ratio of the mass of HPW @ MIL-125(Zn) to the mass of the reaction system is 1: 10-250.
The hydrophilic DES solution is a mixed solution of choline chloride and oxalic acid, and the volume ratio of the choline chloride to the oxalic acid is 1: 1-2.
The invention has the advantages that:
the solid catalyst adopted by the invention has heteropoly acid salt with Lewis acidity
And (3) the reaction is acidic, and a green solvent DES is used as a reaction medium, so that the dehydration process of glucose is realized under the same catalytic system, the product inhibition is reduced, and the final products of 5-HMF and levulinic acid are obtained. In addition, a bifunctional solid catalyst complexThe preparation process of the polyacid salt HPW @ MIL-125(Zn) is simple, and the recovery and the reuse of the catalyst are realized while the high-efficiency catalytic activity of the heteropoly acid is kept.
Drawings
FIG. 1 is an SEM image of solid acid carrier MIL-125 (Zn);
FIG. 2 is an SEM of solid acid catalyst HPW @ MIL-125 (Zn).
Detailed Description
The following detailed description of the embodiments of the invention refers to the accompanying drawings.
Example 1
Terephthalic acid, zinc sulfate, methanol and N, N-Dimethylformamide (DMF) are mixed according to the mass volume ratio of 0.066g:0.037g:9ml:1ml, stirred at 150 ℃ for 24 hours, and a milky white precipitate is collected and repeatedly washed by DMF and anhydrous methanol to obtain white MIL-125(Zn) powder. Then 0.072g of MIL-125(Zn) powder, 1.000g of phosphotungstic heteropoly acid and 50ml of acetonitrile are added into a beaker together, stirred for 90min and dried for 24h at 150 ℃ to obtain solid acid HPW @ MIL-125 (Zn). SEM characterization analysis is carried out on the successfully prepared solid acid carrier MIL-125(Zn) and the solid acid catalyst HPW @ MIL-125(Zn), and as a result, the phosphotungstic heteropoly acid is successfully loaded on the surface of the carrier MIL-125(Zn), and the composite solid acid catalyst HPW @ MIL-125(Zn) is successfully prepared.
Mixing 0.1g glucose and 0.1gHPW@MIL-125(Zn)、2.2Uniformly mixing choline chloride and 2.8g oxalic acid, putting the mixture into a reaction kettle, heating and stirring the mixture at 130 ℃ for 60min, reacting the reaction kettle at 130 ℃ for 4h, collecting a reaction mixture after the reaction is finished, filtering the reaction mixture, collecting filtrate, and separating and purifying the filtrate to obtain levulinic acid and 5-HMF, wherein the yield of the levulinic acid is 52.22 percent and the yield of the 5-hydroxymethylfurfural is 13.04 percent according to high performance liquid chromatography analysis.
Example 2
Terephthalic acid, zinc sulfate, methanol and N, N-Dimethylformamide (DMF) are mixed according to the mass volume ratio of 0.066g:0.037g:9ml:1ml, stirred at 120 ℃ for 12h, and a milky white precipitate is collected and repeatedly washed by DMF and anhydrous methanol to obtain white MIL-125(Zn) powder. And then 0.072g of MIL-125(Zn) powder, 1g of phosphotungstic heteropoly acid and 40ml of acetonitrile are added into a beaker together, stirred for 90min and dried at 120 ℃ for 12h to obtain solid acid HPW @ MIL-125 (Zn). SEM characterization analysis is carried out on the successfully prepared solid acid carrier MIL-125(Zn) and the solid acid catalyst HPW @ MIL-125(Zn), and as a result, the phosphotungstic heteropoly acid is successfully loaded on the surface of the carrier MIL-125(Zn), and the composite solid acid catalyst HPW @ MIL-125(Zn) is successfully prepared.
Mixing 0.1g glucose, 0.02gHPW@MIL-125(Zn)、0.44Uniformly mixing choline chloride and 0.56g oxalic acid, putting the mixture into a reaction kettle, heating and stirring the mixture at 100 ℃ for 40min, reacting the reaction kettle at 120 ℃ for 4h, collecting a reaction mixture after the reaction is finished, filtering the reaction mixture, collecting filtrate, separating and purifying the filtrate to obtain levulinic acid and 5-HMF, and calculating the yield of the levulinic acid to be 41.13 percent and the yield of the 5-HMF to be 10.21 percent by using high performance liquid chromatography.
Example 3
Terephthalic acid, zinc sulfate, methanol and N, N-Dimethylformamide (DMF) are mixed according to the mass volume ratio of 0.037g:0.021g:5ml:5ml, stirred at 120 ℃ for 24h, and a milky white precipitate is collected and repeatedly washed by DMF and anhydrous methanol to obtain white MIL-125(Zn) powder. And then 0.072g of MIL-125(Zn) powder, 1g of phosphotungstic heteropoly acid and 30ml of acetonitrile are added into a beaker together, stirred for 60min and dried for 24h at 120 ℃ to obtain solid acid HPW @ MIL-125 (Zn). SEM characterization analysis is carried out on the successfully prepared solid acid carrier MIL-125(Zn) and the solid acid catalyst HPW @ MIL-125(Zn), and as a result, the phosphotungstic heteropoly acid is successfully loaded on the surface of the carrier MIL-125(Zn), and the composite solid acid catalyst HPW @ MIL-125(Zn) is successfully prepared.
Mixing 0.1g glucose, 0.06gHPW@MIL-125(Zn)、1.32Uniformly mixing choline chloride and 1.68g oxalic acid, putting the mixture into a reaction kettle, heating and stirring the mixture at 140 ℃ for 50min, reacting the reaction kettle at 140 ℃ for 4h, collecting a reaction mixture after the reaction is finished, filtering the reaction mixture, collecting filtrate, separating and purifying the filtrate to obtain levulinic acid and 5-HMF, and calculating the yield of the levulinic acid to be 47.89% and the yield of the 5-HMF to be 7.70% by using high performance liquid chromatography.
Example 4
Terephthalic acid, zinc sulfate, methanol and N, N-Dimethylformamide (DMF) are mixed according to the mass volume ratio of 0.051g to 0.029g to 7ml to 2ml, stirred at 130 ℃ for 24 hours, and a milky white precipitate is collected and repeatedly washed by DMF and anhydrous methanol to obtain white MIL-125(Zn) powder. And then 0.072g of MIL-125(Zn) powder, 1g of phosphotungstic heteropoly acid and 20ml of acetonitrile are added into a beaker together, stirred for 70min and dried for 24h at 130 ℃ to obtain solid acid HPW @ MIL-125 (Zn). SEM characterization analysis is carried out on the successfully prepared solid acid carrier MIL-125(Zn) and the solid acid catalyst HPW @ MIL-125(Zn), and as a result, the phosphotungstic heteropoly acid is successfully loaded on the surface of the carrier MIL-125(Zn), and the composite solid acid catalyst HPW @ MIL-125(Zn) is successfully prepared.
Uniformly mixing 0.1g of glucose, 0.1g of HPW @ MIL-125(Zn), 1.1g of choline chloride and 1.4g of oxalic acid, putting the mixture into a reaction kettle, heating and stirring the mixture at 130 ℃ for 60min, then reacting the reaction kettle at 130 ℃ for 3h, collecting a reaction mixture after the reaction is finished, filtering the reaction mixture, collecting filtrate, separating and purifying the filtrate to obtain levulinic acid and 5-HMF, and calculating the yield of the levulinic acid to be 56.66 percent and the yield of the 5-HMF to be 4.08 percent by using high performance liquid chromatography.
Example 5
Terephthalic acid, zinc sulfate, methanol and N, N-Dimethylformamide (DMF) are mixed according to the mass volume ratio of 0.037g:0.021g:5ml:5ml, stirred for 18h at 150 ℃, milky white precipitate is collected and repeatedly washed by DMF and anhydrous methanol to obtain white MIL-125(Zn) powder. And then 0.072g of MIL-125(Zn) powder, 1g of phosphotungstic heteropoly acid and 50ml of acetonitrile are added into a beaker together, stirred for 60min and dried at 150 ℃ for 18h to obtain solid acid HPW @ MIL-125 (Zn). SEM characterization analysis is carried out on the successfully prepared solid acid carrier MIL-125(Zn) and the solid acid catalyst HPW @ MIL-125(Zn), and as a result, the phosphotungstic heteropoly acid is successfully loaded on the surface of the carrier MIL-125(Zn), and the composite solid acid catalyst HPW @ MIL-125(Zn) is successfully prepared.
Uniformly mixing 0.1g of glucose, 0.1g of HPW @ MIL-125(Zn), 0.5g of choline chloride and 0.5g of oxalic acid, putting the mixture into a reaction kettle, heating and stirring the mixture at 130 ℃ for 40min, reacting the reaction kettle at 130 ℃ for 3h, collecting a reaction mixture after the reaction is finished, filtering the reaction mixture, collecting filtrate, separating and purifying the filtrate to obtain levulinic acid and 5-HMF, and calculating the yield of the levulinic acid to be 50.56% and the yield of the 5-hydroxymethylfurfural to be 6.55% by using high performance liquid chromatography.
The above-mentioned embodiments only express the embodiments of the present invention, but not should be understood as the limitation of the scope of the invention patent, it should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the concept of the present invention, and these all fall into the protection scope of the present invention.
Claims (5)
1. A method for preparing levulinic acid by catalyzing glucose in hydrophilic DES by solid acid, which is characterized by comprising the following steps:
first, the solid acid HPW @ MIL-125(Zn) is prepared
Mixing terephthalic acid, zinc sulfate, methanol and N, N-dimethylformamide DMF, stirring for 12-24 h at 120-150 ℃, collecting milky white precipitate, repeatedly washing with a mixed solution of DMF and anhydrous methanol, drying to obtain white MIL-125(Zn) powder, adding the white MIL-125(Zn) powder into a mixed solution of phosphotungstic heteropoly acid and acetonitrile, stirring for 60-90 min, and drying for 12-24 h at 120-150 ℃ to obtain solid acid HPW @ MIL-125 (Zn); 0.037-0.066 g of terephthalic acid, 0.021-0.037 g of zinc sulfate and 1-5 ml of methanol are correspondingly added into every 5-9 ml of N, N-dimethylformamide;
secondly, placing glucose and hydrophilic DES into a reaction kettle, heating at 100-150 ℃, stirring for 30-60 min until the glucose and the hydrophilic DES are dissolved, then adding HPW @ MIL-125(Zn), stirring for dehydration reaction at 100-150 ℃, reacting for 2-7 h, performing post-treatment after the dehydration reaction to obtain levulinic acid, and simultaneously obtaining 5-HMF, and calculating the yield of the levulinic acid to be more than 50% through high performance liquid chromatography; the mass ratio of the mass of HPW @ MIL-125(Zn) to the mass of the reaction system is 1: 10-250.
2. The method for preparing levulinic acid by catalyzing glucose in the hydrophilic DES by using the solid acid as claimed in claim 1, wherein in the first step, in the mixed solution of the phosphotungstic heteropoly acid and acetonitrile, the mass-to-volume ratio of the phosphotungstic heteropoly acid to the acetonitrile is 1: 5-10, and the mass ratio of the phosphotungstic heteropoly acid to MIL-125(Zn) is 5-25: 1.
3. The method for preparing levulinic acid by catalyzing glucose in the hydrophilic DES by using the solid acid as claimed in claim 1, wherein in the second step, the stirring speed is 300-500 r/min.
4. The method for preparing levulinic acid from glucose in the hydrophilic DES catalyzed by the solid acid according to claim 1, wherein in the second step, the hydrophilic DES solution is a mixed solution of choline chloride and oxalic acid, and the volume ratio of the choline chloride to the oxalic acid is 1: 1-2.
5. The method for preparing levulinic acid by catalyzing glucose in the hydrophilic DES by using the solid acid according to claim 1, wherein in the second step, the mass ratio of the glucose to the hydrophilic DES is 1: 10-50.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115536512A (en) * | 2022-09-15 | 2022-12-30 | 北京理工大学 | Method and device for continuously synthesizing levulinic acid |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103191786A (en) * | 2013-04-23 | 2013-07-10 | 浙江师范大学 | Preparation method of MIL-100(Fe) packaged phosphotungstic heteropolyacid catalyst |
| CN111430640A (en) * | 2020-03-13 | 2020-07-17 | 东华大学 | Preparation and application of titanium-based metal organic framework modified diaphragm |
| CN112279758A (en) * | 2020-10-28 | 2021-01-29 | 中国科学院山西煤炭化学研究所 | Method for preparing and separating levulinic acid from glucose |
-
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103191786A (en) * | 2013-04-23 | 2013-07-10 | 浙江师范大学 | Preparation method of MIL-100(Fe) packaged phosphotungstic heteropolyacid catalyst |
| CN111430640A (en) * | 2020-03-13 | 2020-07-17 | 东华大学 | Preparation and application of titanium-based metal organic framework modified diaphragm |
| CN112279758A (en) * | 2020-10-28 | 2021-01-29 | 中国科学院山西煤炭化学研究所 | Method for preparing and separating levulinic acid from glucose |
Non-Patent Citations (2)
| Title |
|---|
| ROMAIN CANIONI ET AL.: "Stable polyoxometalate insertion within the mesoporous metal organic framework MIL-100(Fe)", 《JOURNAL OF MATERIALS CHEMISTRY》 * |
| TAT BOONYAKARN ET AL.: "Enhanced Levulinic Acid Production from Cellulose by Combined Brønsted Hydrothermal Carbon and Lewis Acid Catalysts", 《INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115536512A (en) * | 2022-09-15 | 2022-12-30 | 北京理工大学 | Method and device for continuously synthesizing levulinic acid |
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Application publication date: 20220412 |