CN111943917A - Method for efficiently preparing 5-hydroxymethylfurfural by pretreating lignocellulose with formic acid - Google Patents
Method for efficiently preparing 5-hydroxymethylfurfural by pretreating lignocellulose with formic acid Download PDFInfo
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- NOEGNKMFWQHSLB-UHFFFAOYSA-N 5-hydroxymethylfurfural Chemical compound OCC1=CC=C(C=O)O1 NOEGNKMFWQHSLB-UHFFFAOYSA-N 0.000 title claims abstract description 38
- RJGBSYZFOCAGQY-UHFFFAOYSA-N hydroxymethylfurfural Natural products COC1=CC=C(C=O)O1 RJGBSYZFOCAGQY-UHFFFAOYSA-N 0.000 title claims abstract description 38
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D307/38—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with substituted hydrocarbon radicals attached to ring carbon atoms
- C07D307/40—Radicals substituted by oxygen atoms
- C07D307/46—Doubly bound oxygen atoms, or two oxygen atoms singly bound to the same carbon atom
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/26—Catalysts comprising hydrides, coordination complexes or organic compounds containing in addition, inorganic metal compounds not provided for in groups B01J31/02 - B01J31/24
Abstract
The invention discloses a method for efficiently preparing 5-hydroxymethylfurfural from lignocellulose pretreated by formic acid, which comprises the following steps: 1) crushing lignocellulose biomass to obtain a lignocellulose raw material; 2) then mixing the solid and the liquid with formic acid solution and then carrying out pretreatment to obtain a solid-liquid mixture; 3) separating the solid-liquid mixture to obtain a solid residue; 4) washing the solid residue to be neutral by formic acid and deionized water in sequence, and drying the solid residue to obtain cellulose coarse pulp; 5) respectively taking alpha-cellulose, microcrystalline cellulose and cellulose brown stock as substrates, taking maleic acid and aluminum chloride as catalysts, and carrying out microwave catalytic reaction in an acetonitrile-water system to obtain the 5-hydroxymethylfurfural. The pretreatment of formic acid effectively realizes the component separation of the lignocellulose raw material, and the maleic acid-aluminum chloride is used as a combined catalyst to directly and efficiently catalyze and formylate the cellulose brown stock in an acetonitrile-water cosolvent system to prepare the high value-added chemical 5-hydroxymethylfurfural.
Description
Technical Field
The invention relates to the field of biomass energy, in particular to a method for preparing 5-hydroxymethylfurfural by performing component separation on lignocellulose pretreated by formic acid to obtain cellulose brown stock and performing efficient catalytic conversion by taking the cellulose brown stock as a raw material.
Background
With the multiple pressure of resource shortage, energy crisis, environmental pollution and the like caused by the continuous consumption of non-renewable fossil resources, how to develop and utilize renewable resources with high efficiency, green and low cost becomes one of the key points of the sustainable development of human beings at present. Among them, lignocellulose resources are used as raw materials to prepare clean fuels and bio-based chemicals to supplement or replace fossil fuels such as coal, petroleum, natural gas, etc. the method is attracting much attention. Lignocellulose is the most abundant renewable resource on the earth, and it is estimated that the dry matter generated by photosynthesis of plants per year is as high as 1500-2000 hundred million tons, but cellulose, hemicellulose and lignin are used as main components and form a compact complex structure through covalent and non-covalent bonding, so that fractionation and utilization of lignocellulose are hindered, and therefore, pretreatment of lignocellulose to realize separation of each component is the key to effective utilization of biomass resources.
In the past decades, researchers have made a lot of research on how to improve the enzymolysis efficiency of cellulose and hemicellulose in lignocellulose and inhibit the inhibition factors in the enzymolysis process, and mainly focus on the following two aspects: (1) developing a novel efficient, economical and feasible pretreatment technology, aiming at destroying the resistance of lignocellulose so as to improve the enzymolysis efficiency; (2) influence factors of the recalcitrance characteristics of the lignocellulose (including the accessibility, crystallinity, hydrogen bonds, lignin structures and the like of the cellulose and the hemicellulose) are analyzed from a mechanism level, and the characteristics of the substrate are clarified, so that a new pretreatment method is constructed through feedback guidance.
The current pretreatment methods are numerous and can be broadly classified into 4 types: biological (microbial degradation), physical (mechanical crushing, radiation, microwave treatment, etc.), chemical (acid treatment, alkali treatment, oxidation treatment, organic solvent treatment, ionic liquid treatment, etc.), and physicochemical (high temperature liquid water treatment, steam explosion treatment, ammonia fiber explosion treatment, CO2Blasting, wet oxygen treatment, etc.). For chemical pretreatment, acid treatment can hydrolyze most of the hemicellulose, but cannot effectively delignify; delignification effect by alkali treatmentThe effect is obvious, but the separation of all components is difficult to realize under mild conditions; the ionic liquid can reduce the crystallinity of cellulose and remove the steric hindrance of lignin, thereby destroying the tight connection structure of cellulose-hemicellulose-lignin, but the ionic liquid is difficult to recover and has high cost and easy environmental pollution. Compared with other traditional processes, the organic solvent is used as a biomass fractionation reagent, and has the characteristics of easiness in recycling of chemical reagents, low degradation degree of dissolved substances, high delignification efficiency, low production cost and the like.
Formic acid, as an organic acid derived from biomass, is low in price, low in boiling point (100.8 ℃), easy to recycle, and suitable for treating biomass at low temperature and normal pressure. During pretreatment, formic acid can break the beta-O-4 bonds of lignin, and hemicellulose is hydrolyzed into monosaccharide and oligosaccharide, so that the lignin and the hemicellulose are dissolved in the formic acid solution, and cellulose is remained in solid residues, thereby effectively separating lignocellulose into high-purity cellulose and high-reaction-activity lignin and hemicellulose. Currently, methods for carrying out fractionation pretreatment on biomass in formic acid aqueous solution, acid-catalyzed formic acid aqueous solution and formic acid-peroxyformic acid mixed solution have been reported, and relevant researches show that the delignification effect is ideal when the formic acid concentration is more than 80%. However, in the pretreatment process of high-concentration formic acid, hydroxyl groups in cellulose and lignin fractions are formylated to a certain extent, and the subsequent saccharification and fermentation processes of the cellulose are severely limited. Thus, currently NaOH, Ca (OH) are commonly used2And (3) further treating formyl groups in the cellulose fraction by using the alkaline solution, and performing deformylation so as to promote the enzymolysis efficiency of the cellulose.
In the process of converting biomass such as cellulose, 5-hydroxymethylfurfural is called as an important platform compound between carbohydrate and petrochemical, and can be used for preparing novel fuel oil and chemical materials such as dimethylfuran, resin plastics and the like through reactions such as hydrogenation, halogenation, oxidative dehydrogenation, esterification, polymerization and the like. Currently, most of relevant researches are to prepare 5-hydroxymethylfurfural by using glucose or fructose as a raw material through acid-catalyzed hydrolysis, but the high raw material cost limits the industrial production of the 5-hydroxymethylfurfural. In contrast, natural macromolecular biomass such as cellulose can directly prepare 5-hydroxymethylfurfural due to wide sources, so that the method is more in line with the concept of green production, and has important theoretical and practical significance for preparing the platform compound 5-hydroxymethylfurfural. However, the dissolving and dispersing ability of cellulose in a solvent is limited due to hydrogen bonds and van der waals force in the cellulose molecules, so that the development of a green high-efficiency catalytic reaction system for realizing oriented conversion of biomass such as cellulose and the like to prepare 5-hydroxymethylfurfural is particularly important.
Disclosure of Invention
The invention aims to provide a method for preparing 5-hydroxymethylfurfural by using formylated cellulose obtained by pretreating lignocellulose with formic acid as a raw material aiming at the defects of the prior art.
The purpose of the invention is realized by the following technical scheme: a method for efficiently preparing 5-hydroxymethylfurfural by pretreating lignocellulose with formic acid comprises the following steps:
1) mechanically crushing lignocellulose biomass to a proper particle size to obtain a lignocellulose raw material for preparing 5-hydroxymethylfurfural;
2) mixing the crushed lignocellulose raw material in the step 1) with a formic acid solution according to a solid-to-liquid ratio of 1 g: 10mL of the mixture is pretreated at 120 ℃ to obtain a solid-liquid mixture;
3) separating the solid-liquid mixture in the step 2) to obtain solid residues;
4) washing the solid residue in the step 3) with 99% formic acid with the washing amount of 75mL, washing the solid residue to be neutral by using deionized water, and drying the solid residue to obtain cellulose coarse pulp;
5) respectively taking alpha-cellulose, microcrystalline cellulose or cellulose coarse pulp in the step 4) as a substrate, taking maleic acid and aluminum chloride as catalysts, carrying out microwave catalytic reaction in an acetonitrile-water system to obtain 5-hydroxymethylfurfural, and determining the content of the 5-hydroxymethylfurfural in the filtrate.
Further, the lignocellulose biomass in the step 1) is agricultural and forestry crops and agricultural and forestry crop processing byproducts, including corn stalks, rice stalks, wheat straws, bagasse, flax stalks or wood.
Further, it is characterized in that the suitable particle size in step 1) is 40 mesh.
Further, the pretreatment conditions in step 2) are as follows: the concentration of the formic acid solution is 99 percent, the pretreatment time is 1 hour, and the stirring speed is 100 r/min.
Further, the drying conditions in step 4) are as follows: drying at 50 deg.C for 24h to constant weight.
Further, the alpha-cellulose and the microcrystalline cellulose in the step 5) are purchased from Shanghai Aladdin Biotechnology Co., Ltd and chemical reagents Co., Ltd of the national drug group, respectively.
Further, the catalytic conditions in step 5) are as follows: 0.05g of substrate was added to a 10mL quartz tube, 0.5mL of maleic acid (0.5M), 0.5mL of aluminum chloride (1.0M) were added as a combined catalyst, and a volume of acetonitrile-deionized water (4/0, 3/1, 2/2, 1/3, v/v) was added to give combined catalyst concentrations of maleic acid and aluminum chloride of 50mM and 100mM, respectively. Sealing the microwave reaction tube, heating the reaction tube to a target reaction temperature of 160 ℃, keeping the temperature for 20min, and magnetically stirring in the heat preservation process.
The invention has the beneficial effects that: the method can effectively realize the component separation of the lignocellulose raw material by formic acid pretreatment at 120 ℃, the cellulose is subjected to formylation modification in the component separation process, the existence of formyl groups seriously inhibits the enzymolysis efficiency of the cellulose, but can improve the hydrophobicity and the thermal stability. According to the invention, maleic acid-aluminum chloride is used as a combined catalyst, and the cellulose brown stock can be directly and efficiently catalyzed and formylated in an acetonitrile-water cosolvent system to prepare the high value-added chemical 5-hydroxymethylfurfural.
Drawings
FIG. 1 is an infrared spectrum of corn stover and cellulose brown stock before and after formic acid pretreatment;
FIG. 2 is a thermogravimetric plot of corn stover and cellulose brown stock before and after formic acid pretreatment;
FIG. 3 is a graph of the dynamic contact angle of corn stover with cellulose brown stock before and after formic acid pretreatment;
FIG. 4 is an XRD spectrum of corn stover and cellulose brown stock before and after formic acid pretreatment;
FIG. 5 is a graph of the molar yield of catalytic reaction components of cellulose brown stock in an acetonitrile-water system (FC-120: cellulose brown stock; CEL: α -cellulose; MCC: microcrystalline cellulose).
Detailed Description
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the following examples.
For illustrative purposes, the lignocellulosic biomass feedstock used in the following examples is corn stover, and indeed the process of the present invention is applicable to a variety of lignocellulosic biomass feedstocks, such as rice straw, wheat straw, sugar cane bagasse, and the like.
Example 1
The lignocellulosic raw material used in this example was corn stover, from Shenyang, Liaoning province, which was crushed and sieved through a 40 mesh standard sieve for further use. The main component determination was carried out on the raw materials used according to the method for determining the lignocellulosic fraction of the American renewable energy laboratory (http:// www.nrel.gov/bioglass/pdfs/42618. pdf) and the results were: 34.50% of cellulose, 18.98% of hemicellulose, 15.94% of lignin, 6.10% of water and 24.50% of the balance.
Step 1, pretreating corn stalks with formic acid
10g of corn straw and 99% formic acid are mixed in a solid-to-liquid ratio of 1:10(g/mL) and placed in a reaction kettle (Parr 4848, 2L), heated to 120 ℃ at a stirring speed of 100r/min and then kept for 1 h. And naturally cooling the reaction kettle to room temperature, carrying out vacuum filtration on the product to obtain solid residue (cellulose coarse pulp), washing the solid residue to be neutral by formic acid and deionized water in sequence, and drying in an oven at 50 ℃ for 24 hours.
Step 2, preparing 5-hydroxymethylfurfural by catalytic conversion of cellulose brown stock pretreated by formic acid
The cellulose coarse pulp, alpha-cellulose and microcrystalline cellulose are taken as substrates to carry out catalytic reaction in a microwave reactor (CEM Discover System). 0.05g of the sample was put into a 10mL quartz tube, and 0.5mL of maleic acid (0.5M), 0.5mL of aluminum chloride (1.0M) as a combined catalyst, and 4mL of acetonitrile was added. The final concentrations of the maleic acid and aluminum chloride combined catalyst were 50mM and 100mM, respectively. Sealing the microwave reaction tube, heating the reaction tube to a target reaction temperature of 160 ℃, keeping the temperature for 20min, and magnetically stirring in the heat preservation process. After the reaction is finished, cooling to room temperature, and measuring the content of the 5-hydroxymethylfurfural in the filtrate by using a high performance liquid chromatograph.
Example 2
The lignocellulosic raw material used in this example was corn stover, from Shenyang, Liaoning province, which was crushed and sieved through a 40 mesh standard sieve for further use. The main component determination was carried out on the raw materials used according to the method for determining the lignocellulosic fraction of the American renewable energy laboratory (http:// www.nrel.gov/bioglass/pdfs/42618. pdf) and the results were: 34.50% of cellulose, 18.98% of hemicellulose, 15.94% of lignin, 6.10% of water and 24.50% of the balance.
Step 1, pretreating corn stalks with formic acid
10g of corn straw and 99% formic acid are mixed in a solid-to-liquid ratio of 1:10(g/mL) and placed in a reaction kettle (Parr 4848, 2L), heated to 120 ℃ at a stirring speed of 100r/min and then kept for 1 h. And naturally cooling the reaction kettle to room temperature, carrying out vacuum filtration on the product to obtain solid residue (cellulose coarse pulp), washing the solid residue to be neutral by formic acid and deionized water in sequence, and drying in an oven at 50 ℃ for 24 hours.
Step 2, preparing 5-hydroxymethylfurfural by catalytic conversion of cellulose brown stock pretreated by formic acid
The cellulose coarse pulp, alpha-cellulose and microcrystalline cellulose are taken as substrates to carry out catalytic reaction in a microwave reactor (CEM Discover System). 0.05g of the sample was added to a 10mL quartz tube, 0.5mL of maleic acid (0.5M), 0.5mL of aluminum chloride (1.0M) as a combined catalyst, and 3mL of acetonitrile and 1mL of deionized water were added. The final concentrations of the maleic acid and aluminum chloride combined catalyst were 50mM and 100mM, respectively. Sealing the microwave reaction tube, heating the reaction tube to a target reaction temperature of 160 ℃, keeping the temperature for 20min, and magnetically stirring in the heat preservation process. After the reaction is finished, cooling to room temperature, and measuring the content of the 5-hydroxymethylfurfural in the filtrate by using a high performance liquid chromatograph.
Example 3
The lignocellulosic raw material used in this example was corn stover, from Shenyang, Liaoning province, which was crushed and sieved through a 40 mesh standard sieve for further use. The main component determination was carried out on the raw materials used according to the method for determining the lignocellulosic fraction of the American renewable energy laboratory (http:// www.nrel.gov/bioglass/pdfs/42618. pdf) and the results were: 34.50% of cellulose, 18.98% of hemicellulose, 15.94% of lignin, 6.10% of water and 24.50% of the balance.
Step 1, pretreating corn stalks with formic acid
10g of corn straw and 99% formic acid are mixed in a solid-to-liquid ratio of 1:10(g/mL) and placed in a reaction kettle (Parr 4848, 2L), heated to 120 ℃ at a stirring speed of 100r/min and then kept for 1 h. And naturally cooling the reaction kettle to room temperature, carrying out vacuum filtration on the product to obtain solid residue (cellulose coarse pulp), washing the solid residue to be neutral by formic acid and deionized water in sequence, and drying in an oven at 50 ℃ for 24 hours.
Step 2, preparing 5-hydroxymethylfurfural by catalytic conversion of cellulose brown stock pretreated by formic acid
The cellulose coarse pulp, alpha-cellulose and microcrystalline cellulose are taken as substrates to carry out catalytic reaction in a microwave reactor (CEM Discover System). 0.05g of the sample was added to a 10mL quartz tube, 0.5mL of maleic acid (0.5M), 0.5mL of aluminum chloride (1.0M) as a combined catalyst, and 2mL of acetonitrile and 2mL of deionized water were added. The final concentrations of the maleic acid and aluminum chloride combined catalyst were 50mM and 100mM, respectively. Sealing the microwave reaction tube, heating the reaction tube to a target reaction temperature of 160 ℃, keeping the temperature for 20min, and magnetically stirring in the heat preservation process. After the reaction is finished, cooling to room temperature, and measuring the content of the 5-hydroxymethylfurfural in the filtrate by using a high performance liquid chromatograph.
Example 4
The lignocellulosic raw material used in this example was corn stover, from Shenyang, Liaoning province, which was crushed and sieved through a 40 mesh standard sieve for further use. The main component determination was carried out on the raw materials used according to the method for determining the lignocellulosic fraction of the American renewable energy laboratory (http:// www.nrel.gov/bioglass/pdfs/42618. pdf) and the results were: 34.50% of cellulose, 18.98% of hemicellulose, 15.94% of lignin, 6.10% of water and 24.50% of the balance.
Step 1, pretreating corn stalks with formic acid
10g of corn straw and 99% formic acid are mixed in a solid-to-liquid ratio of 1:10(g/mL) and placed in a reaction kettle (Parr 4848, 2L), heated to 120 ℃ at a stirring speed of 100r/min and then kept for 1 h. And naturally cooling the reaction kettle to room temperature, carrying out vacuum filtration on the product to obtain solid residue (cellulose coarse pulp), washing the solid residue to be neutral by formic acid and deionized water in sequence, and drying in an oven at 50 ℃ for 24 hours.
Step 2, preparing 5-hydroxymethylfurfural by catalytic conversion of cellulose brown stock pretreated by formic acid
The cellulose coarse pulp, alpha-cellulose and microcrystalline cellulose are taken as substrates to carry out catalytic reaction in a microwave reactor (CEM Discover System). 0.05g of the sample was added to a 10mL quartz tube, 0.5mL of maleic acid (0.5M), 0.5mL of aluminum chloride (1.0M) as a combined catalyst, and 1mL of acetonitrile and 3mL of deionized water were added. The final concentrations of the maleic acid and aluminum chloride combined catalyst were 50mM and 100mM, respectively. Sealing the microwave reaction tube, heating the reaction tube to a target reaction temperature of 160 ℃, keeping the temperature for 20min, and magnetically stirring in the heat preservation process. After the reaction is finished, cooling to room temperature, and measuring the content of the 5-hydroxymethylfurfural in the filtrate by using a high performance liquid chromatograph.
The results of infrared spectroscopic analysis of the corn stover and cellulose brown stock of examples 1 to 4 are shown in FIG. 1. 1732cm in corn stalk after pretreatment with formic acid-1The absorption peak at (A) is transferred to 1714cm in the cellulose brown stock-1Here, the carbonyl (C ═ O) vibration is attributed to the formylation reaction between formic acid and cellulose hydroxyl groups. 1617 and 1516cm in the cellulose brown stock-1The absorption peak is obviously reduced compared with the corn straw, and the aromatic skeleton vibration shows that the formic acid treatment can realize high-efficiency delignification. In addition, the cellulose coarse pulp is at 1246 and 1077cm-1The absorption peaks which disappear completely are all related to C-O stretching vibration in the hemicellulose, which indicates that the hemicellulose is degraded in the pretreatment process. The results show that after formic acid treatment, hemicellulose and lignin can be effectively removed, and the cellulose brown stock with high cellulose purity is obtained.
The results of the thermal stability analysis of the corn stover and cellulose brown stock in examples 1-4 are shown in FIG. 2. The corn stalk and cellulose brown stock mainly goes through three stages: the first stage (40-120 ℃) is mainly the evaporation of free water in the sample; in the second stage (120-280 ℃), due to degradation of hemicellulose and splitting of glycosidic bonds in cellulose, only a small peak appears in corn straws at 225 ℃ in the second stage, and degradation of hemicellulose is indicated; the last stage (280-400 ℃) is associated with the degradation of cellulose and part of the lignin, and all samples present a significant loss of quality at this stage. The above results indicate that the significant improvement in the thermal stability of the cellulose brown stock is attributed to the removal of non-cellulosic subcomponents such as hemicellulose, low molecular weight lignin and pectin, the degradation temperature of which is lower than that of cellulose. On the other hand, the more formylated cellulose brown stock showed better thermal stability, indicating that formylation modification can improve the thermal stability of the material.
The results of dynamic contact angle analysis of the corn stalks and the cellulose brown stock in examples 1 to 4 are shown in fig. 3. It can be seen from the figure that the resistance to hydrophilicity of the cellulose brown stock (75.5s) is significantly better than that of the corn stover (1.0 s). On the surface of the corn stalk, water molecules easily form hydrophilic hydroxyl groups, so that water drops are quickly diffused on the surface to quickly reduce the contact angle until the water drops are completely absorbed by the corn stalk for 1.0s (finally, the corn stalk and cellulose coarse pulp completely absorb water and swell to form a convex angle on the surface, which is not an actual contact angle). Lignin is generally considered to be more hydrophobic than cellulose due to its aromatic structure and lower hydroxyl content, but the results show that cellulose brown stock with lower lignin content exhibits the most excellent hydrophobicity, probably due to a greater degree of formylation of the cellulose brown stock after formic acid pretreatment, thereby increasing its hydrophobic properties.
The crystallinity analysis was performed on the corn stover and cellulose brown stock in examples 1 to 4, and the X-ray diffraction spectrum (XRD) was scanned over the entire diffraction region at an angle of 2 θ, and 2 θ was taken as the abscissa of the X-ray diffraction spectrum, and the results are shown in fig. 4. Cellulose crystals in the cellulose brown stock are 22.2 ° (I) at 2 θ ═ 22.2 °002) And35.0°(I040) A sharp diffraction peak appears, and cellulose molecules are originally connected into cellulose micelles in a hydrogen bond mode, which shows that after lignocellulose is pretreated by formic acid, partial hydrogen bonds are broken, so that an amorphous area is damaged, and a crystalline area is difficult to damage due to a compact structure of the crystalline area. Therefore, after formic acid pretreatment, lignocellulose undergoes crystal structure change and intramolecular rearrangement reactions, and cellulose, hemicellulose and lignin are subjected to component separation. In addition, the crystallinity of the cellulose brown stock was significantly increased compared to untreated corn stover, further indicating that formic acid pretreatment can remove amorphous hemicellulose and lignin.
The results of the catalytic conversion performance analysis of the cellulose brown stock in examples 1 to 4 are shown in fig. 5. In an acetonitrile-water system, the molar yield of 5-hydroxymethylfurfural of cellulose brown stock is obviously higher than that of alpha-cellulose and microcrystalline cellulose, and the interaction between the cellulose brown stock and acetonitrile can be enhanced probably because the cellulose brown stock contains a large amount of acetonitrile-philic formyl radicals, and the cellulose brown stock and the acetonitrile are subjected to Lewis acid (AlCl)3) Thereby promoting the conversion of the cellulose brown stock into glucose. Moreover, acetonitrile can bring water closer to glucose, and tight binding of water molecules to glucose epoxy and carbon 5 can promote isomerization of glucose to fructose, which can further convert fructose to 5-hydroxymethylfurfural. The results show that the cellulose coarse pulp has higher selectivity in an acetonitrile-water system.
Finally, it is also noted that the above-mentioned lists merely illustrate a few specific embodiments of the invention. It is obvious that the invention is not limited to the above embodiments, but that many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.
Claims (7)
1. The method for efficiently preparing 5-hydroxymethylfurfural by pretreating lignocellulose with formic acid is characterized by comprising the following steps of:
1) mechanically crushing lignocellulose biomass to a proper particle size to obtain a lignocellulose raw material for preparing 5-hydroxymethylfurfural;
2) mixing the crushed lignocellulose raw material in the step 1) with a formic acid solution according to a solid-to-liquid ratio of 1 g: 10mL of the mixture is pretreated at 120 ℃ to obtain a solid-liquid mixture;
3) separating the solid-liquid mixture in the step 2) to obtain solid residues;
4) washing the solid residue in the step 3) with 99% formic acid with the washing amount of 75mL, washing the solid residue to be neutral by using deionized water, and drying the solid residue to obtain cellulose coarse pulp;
5) respectively taking alpha-cellulose, microcrystalline cellulose or cellulose coarse pulp in the step 4) as a substrate, taking maleic acid and aluminum chloride as catalysts, carrying out microwave catalytic reaction in an acetonitrile-water system to obtain 5-hydroxymethylfurfural, and determining the content of the 5-hydroxymethylfurfural in the filtrate.
2. The method for efficiently preparing 5-hydroxymethylfurfural from formic acid pretreated lignocellulose as claimed in claim 1, wherein the lignocellulose biomass in the step 1) is agricultural and forestry crops and agricultural and forestry crop processing byproducts, and comprises corn stalks, rice stalks, wheat stalks, bagasse, flax stalks or wood.
3. The method for efficiently preparing 5-hydroxymethylfurfural from formic acid-pretreated lignocellulose as claimed in any one of claims 1 or 2, wherein the suitable particle size in the step 1) is 40 meshes.
4. The method for efficiently preparing 5-hydroxymethylfurfural by formic acid pretreated lignocellulose according to claim 1, wherein the pretreatment conditions in the step 2) are as follows: the concentration of the formic acid solution is 99 percent, the pretreatment time is 1 hour, and the stirring speed is 100 r/min.
5. The method for efficiently preparing 5-hydroxymethylfurfural by formic acid pretreated lignocellulose according to claim 1, wherein the drying conditions in the step 4) are as follows: drying at 50 deg.C for 24h to constant weight.
6. The method for efficiently preparing 5-hydroxymethylfurfural from formic acid-pretreated lignocellulose as recited in claim 1, wherein the alpha-cellulose and the microcrystalline cellulose in the step 5) are purchased from Shanghai Aladdin Biotechnology Ltd and national drug group chemical reagent Ltd, respectively.
7. The method for efficiently preparing 5-hydroxymethylfurfural by formic acid pretreated lignocellulose according to claim 1, characterized in that the catalytic conditions in the step 5) are as follows: 0.05g of substrate was added to a 10mL quartz tube, 0.5mL of maleic acid (0.5M), 0.5mL of aluminum chloride (1.0M) were added as a combined catalyst, and a volume of acetonitrile-deionized water (4/0, 3/1, 2/2, 1/3, v/v) was added to give combined catalyst concentrations of maleic acid and aluminum chloride of 50mM and 100mM, respectively. Sealing the microwave reaction tube, heating the reaction tube to a target reaction temperature of 160 ℃, keeping the temperature for 20min, and magnetically stirring in the heat preservation process.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115928479A (en) * | 2022-11-17 | 2023-04-07 | 安徽工程大学 | Method for efficiently deconstructing lignocellulose raw material by coupling carbon dioxide with organic solvent |
| WO2023058662A1 (en) * | 2021-10-04 | 2023-04-13 | 株式会社ダイセル | Lignocellulose solution and shaped article, and production method therefor |
| US20230159831A1 (en) * | 2021-11-22 | 2023-05-25 | South China Agricultural University | Method for upgrading pyrolysis oil through seawater electrochemical pretreatment of biomass and use thereof |
-
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Non-Patent Citations (1)
| Title |
|---|
| CAIDI JIN ET AL.: "Corn stover valorization by one-step formic acid fractionation and formylation for 5-hydroxymethylfurfural and high guaiacyl lignin production", 《BIORESOURCE TECHNOLOGY》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023058662A1 (en) * | 2021-10-04 | 2023-04-13 | 株式会社ダイセル | Lignocellulose solution and shaped article, and production method therefor |
| US20230159831A1 (en) * | 2021-11-22 | 2023-05-25 | South China Agricultural University | Method for upgrading pyrolysis oil through seawater electrochemical pretreatment of biomass and use thereof |
| US11732196B2 (en) * | 2021-11-22 | 2023-08-22 | South China Agricultural University | Method for upgrading pyrolysis oil through seawater electrochemical pretreatment of biomass feedstock |
| CN115928479A (en) * | 2022-11-17 | 2023-04-07 | 安徽工程大学 | Method for efficiently deconstructing lignocellulose raw material by coupling carbon dioxide with organic solvent |
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