CN114292185B - Method for preparing p-coumaric acid ester by catalyzing lignin depolymerization through ionic liquid - Google Patents
Method for preparing p-coumaric acid ester by catalyzing lignin depolymerization through ionic liquid Download PDFInfo
- Publication number
- CN114292185B CN114292185B CN202111529145.7A CN202111529145A CN114292185B CN 114292185 B CN114292185 B CN 114292185B CN 202111529145 A CN202111529145 A CN 202111529145A CN 114292185 B CN114292185 B CN 114292185B
- Authority
- CN
- China
- Prior art keywords
- ionic liquid
- lignin
- coumarate
- preparing
- catalyzed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
The invention discloses a method for preparing p-coumaric acid ester by catalyzing lignin depolymerization by ionic liquid. The method takes herbaceous lignin as a raw material, acidic functionalized ionic liquid as a catalyst and low-carbon alcohol as a reaction medium, and obtains coumarate by ester exchange technology under the conditions of 0.5-2.0 MPa pressure, 110-180 ℃ temperature and inert atmosphere; a p-coumarate yield of 11.8wt.% and a p-coumarate selectivity of 72.5% were highly obtainable. After the ionic liquid is repeatedly used for 10 times, the catalytic activity is not obviously reduced. The method has the advantages of relatively mild reaction conditions, high selectivity of single high value-added chemicals, renewable raw materials, reusable catalyst and the like, and the method is simple in process operation and can realize intermittent and continuous production.
Description
Technical Field
The invention relates to p-coumarate which is a high value-added chemical, in particular to a method for preparing p-coumarate by catalyzing directional conversion of herbaceous lignin by ionic liquid, and belongs to the field of efficient resource utilization of renewable agricultural and forestry wastes.
Background
The p-coumaric acid and the ester thereof are important raw materials for synthesizing spices, cosmetics, foods and health care products, can also be used as a medical intermediate for preparing medicines such as an epinephrine-resistant medicine esmolol and the like, and have important effects on the aspects of immunoregulation, cardiovascular protection, diabetes prevention and improvement, neuroprotection, melanin formation inhibition, skin aging delay and the like. The side chain of the molecule has double bonds, the p-coumaric acid and the ester thereof can also be used as a precursor of a polymer to prepare a functional polymer material, and the polymer material has wide application prospect and great application potential in the field of optical fiber communication.
Currently, p-coumaric acid and esters thereof are mainly prepared from petroleum-based chemicals by chemical synthesis or biosynthesis. For example, p-hydroxybenzaldehyde and acetic anhydride are used as raw materials, potassium carbonate is used as a catalyst, and the synthesis of p-coumaric acid by a one-pot method is realized through Perkin reaction under the microwave-assisted condition. However, the above processes generally have technical bottlenecks such as complicated reaction process, high energy consumption, many byproducts and the like, and particularly, with the deep promotion of policy implementation of 'carbon peak reaching and carbon neutralization' and strategy of 'sustainable development', it is very important to find a green preparation method of p-coumarate for replacing a petroleum-based route.
Lignin is one of the important components of biomass, is a natural aromatic polymer with the most abundant content in nature, and particularly part of herbal lignin contains p-coumaric acid (ester) structures. Compared with the lignin with other structural units mainly connected by C-O bonds or C-C bonds, the p-coumaric acid structure in the herbal lignin is mainly connected by ester groups and other structural units, which also means that the selective conversion of the lignin to prepare the p-coumaric acid ester with high added value can be realized by designing a catalytic system. In recent years, li et al (selected catalytic fouling of the H unit in bacterial lignin for metallic p-hydrolyzed production over metallic-based ionic liquids, green chem.,2018,20, 3743-3752) used bagasse lignin as a raw material and a metal-based ionic liquid [ Bmim ] as a metal-based ionic liquid][FeCl 4 ]As a catalyst, reaction was carried out at 145 ℃ for 6h to give a yield of 7.1wt.% methyl p-coumarate. Chinese patent application CN201911410781.0 and Chinese patent application CN202011305496.5 respectively use cupric salts such as cupric chloride and the like and molybdenum oxide loaded by a molecular sieve as catalysts to realize conversion of bagasse lignin and the like to obtain p-flavorAnd (3) preparing the bean acid ester. However, the homogeneous or heterogeneous catalysts need to involve heavy metal ions, and the inevitable loss of metal ions in the reaction process results in increased side reactions and increased difficulty in product separation and purification, and the use of heavy metal ions is also not beneficial to the environment and has the original purpose of violating the green preparation of high value-added chemicals.
Disclosure of Invention
The invention aims to provide a new green preparation technology of p-coumaric acid ester which is a fine chemical with high added value and replaces a petroleum-based route. The technology has simple process and mild conditions, and is suitable for the purpose of batch production and continuous production.
The purpose of the invention is realized by the following technical scheme:
a method for preparing p-coumaric acid ester by catalyzing lignin depolymerization through ionic liquid comprises the following steps: taking herbal lignin as a raw material, taking acidic functionalized ionic liquid as a catalyst, taking low-carbon alcohol as a reaction medium, and carrying out ester exchange under the conditions of 0.5-2.0 MPa pressure, 110-180 ℃ and inert atmosphere to obtain coumarate; the acidic functionalized ionic liquid is one of alkyl imidazole hydrogen sulfate, sulfoalkyl imidazole hydrogen sulfate, alkyl pyridine hydrogen sulfate, sulfoalkyl pyridine hydrogen sulfate, alkyl quaternary ammonium hydrogen sulfate and sulfoalkyl quaternary ammonium hydrogen sulfate.
To further achieve the object of the present invention, preferably, the acidic functionalized ionic liquid is one of the following structural formulas:
preferably, the lignin is organic solvent-based herbaceous lignin.
Preferably, the biomass of the organic solvent-based herbaceous lignin is derived from one of corncobs, straws, wheat straws, corn stover, sorghum stover, bagasse, miscanthus, pennisetum and switchgrass.
Preferably, the lower alcohol is one or more of methanol, ethanol, propanol and isopropanol.
Preferably, the gas of the inert atmosphere is one of nitrogen, argon or helium.
Preferably, the reaction time of the ester exchange is 1 to 6 hours; the transesterification reaction is carried out in a rotating reactor, the rotating speed of which is 400-700 r/min.
Preferably, the dosage of the acidic functionalized ionic liquid is 0.05-2.5 mol/kg lignin; the volume-mass ratio of the reaction medium to the lignin is 5-25, wherein the volume unit is milliliter and the mass unit is gram.
Preferably, the purification process is column separation, and the volume ratio of eluent of column separation is 1: 1-3 of mixed solution of petroleum ether and ethyl acetate.
Preferably, the acidic functionalized ionic liquid is reused; extracting the repeatedly used acidic functionalized ionic liquid by dichloromethane, removing the extracting agent by rotary evaporation, and then placing the acidic functionalized ionic liquid in a vacuum drying oven for drying for 6 to 12 hours to obtain the acidic functionalized ionic liquid.
According to the characteristic that the herbal lignin structure is rich in p-coumaric acid, acidic functionalized ionic liquid is used as a catalyst, low-carbon alcohol such as methanol is used as a reaction medium, and the reaction is carried out for 1-6 hours at 110-180 ℃ through ester exchange technical reaction, so that the reproducible herbal lignin is selectively converted to prepare the high-added-value chemical p-coumaric acid ester, and the green new preparation technology of the high-added-value fine chemical p-coumaric acid ester, which replaces a petroleum-based route, is obtained.
Compared with the prior art, the invention has the following advantages and effects:
1) The invention constructs a functionalized ionic liquid catalytic system based on the intrinsic characteristic that the herbaceous lignin molecules are rich in p-coumaric acid structures and are mainly connected with other structural units through ester groups, and utilizes the principle of ester exchange reaction to realize the selective fracture of the p-coumaric acid structural units in the herbaceous lignin structures under mild conditions, thereby obtaining the fine chemical p-coumaric acid ester with high added value and wide application. The purpose of green preparation of bulk chemicals for replacing a petroleum-based route is achieved by starting from renewable raw materials.
2) Compared with the prior art for preparing p-coumarate, the method has the greatest advantage that the method for preparing p-coumarate by using the renewable agricultural and forestry waste component lignin as the raw material has the advantages of reproducibility of the raw material, reusability of the catalyst and accordance with the requirements of the current 'double-carbon' strategy. Compared with the preparation method of the coumarate by the lignin group reported in a small amount of existing documents, the catalyst adopted by the invention is functional ionic liquid, does not relate to metal ions and halogen ions, and can avoid the influence of the catalyst on the environment.
3) Compared with the prior lignin depolymerization technology, the method has milder reaction conditions, and the constructed catalytic system is based on the characteristic of lignin structure difference, so the selectivity of the product obtained by the method is obviously higher than that of the prior lignin depolymerization technology.
4) The catalytic system constructed by the method has the remarkable advantages of high activity, simple operation, easy product separation, environmental friendliness, reusability of the catalyst and the like.
5) The medium adopted by the method can be reused by simple distillation.
6) The invention has mild reaction condition and simple process operation, and can realize discontinuous or continuous reaction.
Drawings
FIG. 1 shows [ bSmim ] obtained in example 1][HSO 4 ]Gas chromatography (GC-FID) spectrum of bagasse lignin depolymerization product in the catalytic system.
FIG. 2 is a mass spectrum of the product obtained in example 1 on methyl coumarate.
FIG. 3 is a Fourier transform infrared (FT-IR) spectrum of the product obtained in example 1 on methyl coumarate.
FIG. 4 shows the product pair obtained in example 1Nuclear magnetic resonance hydrogen spectrum of methyl coumarate (A) 1 H NMR) spectrum.
FIG. 5 is the NMR spectrum of methyl p-coumarate obtained in example 1 (C 13 C NMR) spectrum.
FIG. 6 is a graph of ionic liquid reuse performance.
Detailed Description
The present invention will be further described with reference to the following examples for better understanding of the present invention, but the embodiments of the present invention are not limited thereto.
Example 1: ionic liquid 1-butanesulfonic acid group-3-methylimidazole hydrogen sulfate ([ bSmim [ ])]HSO 4 ) Method for preparing p-coumaric acid methyl ester by catalyzing selective depolymerization of bagasse lignin
A method for preparing p-coumaric acid ester by catalyzing lignin depolymerization through ionic liquid comprises the following steps: 2mmol of ionic liquid 1-butanesulfonic acid group-3-methylimidazole bisulfate ([ bSmim [ ])]HSO 4 ) 2g of organic solvent type bagasse lignin and 20mL of methanol were charged into a 50mL high-pressure reaction vessel (maximum operating pressure 20MPa, maximum operating temperature 300 ℃ C.). The reactor was closed and the reactor was replaced 3 times with high purity argon (purity greater than 99.9%) to vent the air from the kettle and then pressurized to 0.5MPa. The reaction mixture was heated to 140 ℃ and reacted for 4h with stirring at 600r/min. The method comprises the steps of recovering and reusing methanol as a reaction medium by adopting a rotary evaporation mode, extracting small molecular chemicals obtained by lignin depolymerization by adopting an ethyl acetate extraction mode, precipitating incompletely reacted lignin by adding water, separating the incompletely reacted lignin from a solution by adopting a 0.22um organic membrane filtration mode, and recovering the ionic liquid catalyst by adopting a dichloromethane extraction mode. The liquid remaining after the reaction was transferred to a beaker, and 50mL of deionized water was added thereto. And (2) mixing the raw materials in ethyl acetate: petroleum ether volume ratio 2: the mixed solution of 1 is eluent, and the methyl p-coumarate chemical is obtained by means of column separation. The results show that: the depolymerization rate of bagasse lignin was 56.2%, the mass yield of p-coumaric acid methyl ester was 11.8wt.%, and the selectivity was 72.5%.
The depolymerization rate of lignin obtained in this example is calculated by formula 1:
equation 1: lignin depolymerization rate = (1-mass of incompletely reacted lignin/mass of lignin raw material) × 100%
The yield of p-coumaric acid methyl ester obtained in the example is calculated by formula 2
Equation 2: yield of p-coumaric acid methyl ester = p-coumaric acid methyl ester mass/mass of lignin raw material × 100%
The selectivity of p-coumaric acid methyl ester obtained in the example is calculated by formula 3
Equation 3: p-coumaric acid methyl ester selectivity = p-coumaric acid methyl ester mass/volatile small molecule product mass × 100%
The small molecule product obtained in the embodiment refers to a product which can be directly detected by gas chromatography, and the compounds are qualitatively analyzed by gas chromatography-mass spectrometry, and quantitatively analyzed by gas chromatography. The results of GC-MS analysis (FIG. 1) show that the compound mainly comprises p-coumaric acid methyl ester and other phenolic compounds such as 4-ethylphenol and the like.
The structure of the methyl p-coumarate obtained in this example was determined by Fourier Infrared Spectroscopy (FT-IR), nuclear magnetic resonance (F:) 1 H-NMR， 13 C-NMR) and mass spectrum, and the results are shown in the attached figures 2-5.
FIG. 2 is a mass spectrum of the product obtained in example 1 on methyl coumarate. Wherein the characteristic mass spectral fragments attributed to m/z =178, 147, 119, 91, 65 and 45 of p-coumaric acid methyl ester are clearly visible.
FIG. 3 is a FT-IR spectrum of the product obtained in example 1 against methyl coumarate. Wherein the length of the groove is 3380cm -1 Is classified as phenolic hydroxyl group stretching vibration, 1687cm -1 The strong transmission peak is attributed to the stretching vibration of carbonyl group, combined with 1198cm -1 And 1170cm -1 The infrared peak of the symmetrical C-O chemical bond is shown to indicate that the molecule of the compound contains ester group; 1614cm -1 ，1542cm -1 ，1431cm -1 ，1281cm -1 And 833cm -1 The infrared peak indicates that the benzene ring of the para-group exists in the compound.
FIG. 4 shows the product obtained in example 1, p-coumaric acid methyl ester 1 H NMR spectrum. A characteristic peak at 10.04ppm is attributed to a hydrogen atom in the phenolic hydroxyl group; 7.57ppm,6.81ppm and 6.42ppmThe heavy peak belongs to a benzene ring and a hydrogen atom of the conjugated olefin; the multiplet at 3.46ppm is attributed to the hydrogen atom in the methoxy group.
FIG. 5 shows the product obtained in example 1, p-coumaric acid methyl ester 13 C NMR spectrum. 167ppm characteristic peak attributed to carbonyl carbon in ester group; the characteristic peaks at 160ppm,130ppm,125ppm and 116ppm show that para-substituted phenolic structure exists in the compound, and the characteristic peaks at 145ppm and 114ppm respectively belong to carbon atoms in olefin structure; the characteristic peak at 52ppm is assigned to the methyl carbon atom in the methoxy group.
Therefore, as can be seen from the structural characterization data obtained in FIGS. 2-5, the obtained product is p-coumaric acid methyl ester chemical with high purity.
The embodiment provides a method for preparing methyl p-coumarate of an important petroleum-based fine chemical by catalyzing selective depolymerization of lignin through ionic liquid, which takes lignin in renewable agricultural and forestry wastes as a raw material and provides a green preparation strategy for replacing an important chemical product of a petroleum-based route. Compared with the current petroleum-based route, the method has simple process and renewable raw materials; compared with the current lignin-based production technology of p-coumaric acid methyl ester (Green chem.,2018,20,3743-3752, CN201911410781.0), the catalyst adopted by the invention does not contain heavy metal ions and halogen ions, is more environment-friendly, and has the efficiency (yield of p-coumaric acid methyl ester) which is remarkably higher than that of a metal halide ionic liquid (7.1 wt.%) and copper salt (4 wt.%) catalytic system adopted by a control document.
Example 2: ionic liquid butanesulfonic acid pyridine bisulfate ([ bSPy)]HSO 4 ) Method for preparing p-coumaric acid methyl ester by catalyzing selective depolymerization of corncob lignin
The present embodiment is different from embodiment 1 in that:
the adopted catalyst is butanesulfonic pyridine bisulfate ionic liquid ([ bSPy)]HSO 4 ) (ii) a The dosage of the catalyst is 5mmol; the adopted lignin is organic solvent type lignin derived from corncobs, and the dosage of the lignin is 5g; the reaction temperature is 150 ℃; the reaction time is 3h; the stirring speed of the reactor is 500r/min; p-coumaric acid ester column separation and purification stationThe eluent is adopted in a volume ratio of 1: ethyl acetate and petroleum ether of 1. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained corncob lignin is 56.8 percent; the yield to methyl coumarate was 10.5wt.% with a selectivity of 73.2%.
Example 3: ionic liquid tributylamine hydrogen sulfate ([ bSb ] 3 N]HSO 4 ) Method for preparing ethyl p-coumarate by catalyzing selective depolymerization of corn straw lignin
The present embodiment is different from embodiment 1 in that:
the adopted catalyst is butanesulfonic tributylamine bisulfate ionic liquid ([ bSb ] 3 N]HSO 4 ) (ii) a The dosage of the catalyst is 1mmol; the adopted lignin is organic solvent type lignin derived from corncobs, and the dosage of the lignin is 2.5g; the reaction temperature is 180 ℃; the reaction time is 6h; the stirring speed of the reactor is 500r/min; the eluent adopted for the separation and purification of coumarate column is 1:1 ethyl acetate and petroleum ether. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained organic solvent type corn straw lignin is 62.7 percent; the yield to methyl coumarate was 8.6wt.% and the selectivity was 65.2%.
Example 4: ionic liquid 1-propanesulfonic acid group-3-methylimidazole bisulfate ([ pSmim)]HSO 4 ) Method for preparing isopropyl p-coumarate by catalyzing selective depolymerization of straw lignin
The present embodiment is different from embodiment 1 in that:
the ionic liquid catalyst is 1-propanesulfonic acid group-3-methylimidazole hydrogen sulfate ([ pSmim)]HSO 4 ) (ii) a The dosage of the catalyst is 5mmol; the adopted lignin is organic solvent type lignin derived from straws, and the dosage of the lignin is 2.5g; the reaction medium is isopropanol; the reaction temperature is 180 ℃; the reaction time is 6h; the reactor stirring speed was 700r/min. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained corncob lignin is 73.2 percent; the yield to isopropyl coumarate was 6.7wt.% and the selectivity was 45.8%.
Example 5: ionic liquid 1-propanesulfonic acid group-3-methylimidazole hydrogen sulfate ([ pSmim)]HSO 4 ) Preparation of propyl p-coumarate by catalyzing selective depolymerization of sorghum straw lignin
The present embodiment is different from embodiment 1 in that:
the ionic liquid catalyst is 1-propanesulfonic acid group-3-methylimidazole hydrogen sulfate ([ pSmim)]HSO 4 ) (ii) a The dosage of the catalyst is 5mmol; the adopted lignin is organic solvent type lignin derived from sorghum straws, and the dosage of the lignin is 5g; the reaction medium is n-propanol; the inert gas is helium, and the reaction temperature is 170 ℃; the reaction time is 1h; the reactor stirring speed was 400r/min. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained sorghum straw lignin is 67.5%; the yield to propyl coumarate was 5.9wt.% and the selectivity was 55.2%.
Example 6: ionic liquid 1-butanesulfonic acid group-3-methylimidazole bisulfate ([ bSmim)]HSO 4 ) Method for preparing ethyl p-coumarate by catalyzing selective depolymerization of mango lignin
The present embodiment is different from embodiment 1 in that:
the ionic liquid catalyst is 1-butanesulfonic acid group-3-methylimidazole hydrogen sulfate ([ bSmim)]HSO 4 ) (ii) a The dosage of the catalyst is 5mmol; the adopted lignin is organic solvent type lignin derived from miscanthus sinensis, and the dosage of the lignin is 5g; the reaction medium is ethanol; the inert gas is helium, and the reaction temperature is 150 ℃; the reaction time is 6h; the reactor stirring speed was 600r/min. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained mango lignin is 58.9 percent; the yield of propyl p-coumarate was 9.8wt.% with a selectivity of 66.7%.
Example 7: ionic liquid 1-butanesulfonic acid group-3-methylimidazole hydrogen sulfate ([ bSmim [ ])]HSO 4 ) Method for preparing ethyl p-coumarate by catalyzing selective depolymerization of pennisetum alopecuroides lignin
The present embodiment is different from embodiment 1 in that:
the ionic liquid catalystThe reagent is 1-butanesulfonic acid group-3-methylimidazole bisulfate ([ bSmim [)]HSO 4 ) (ii) a The using amount of the catalyst is 5mmol; the adopted lignin is organic solvent type lignin derived from pennisetum and the dosage of the lignin is 5g; the reaction medium is ethanol; the inert gas is helium, and the reaction temperature is 150 ℃; the reaction time is 6h; the reactor stirring speed was 600r/min. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained pennisetum lignin is 62.1 percent; the yield to propyl coumarate was 10.2wt.% with a selectivity of 68.3%.
Example 8: ionic liquid 1-butanesulfonic acid group-3-methylimidazole hydrogen sulfate ([ bSmim [ ])]HSO 4 ) Method for preparing ethyl p-coumarate by catalyzing selective depolymerization of switchgrass lignin
The present embodiment is different from embodiment 1 in that:
the ionic liquid catalyst is 1-butanesulfonic acid group-3-methylimidazole bisulfate ([ bSmim)]HSO 4 ) (ii) a The using amount of the catalyst is 5mmol; the adopted lignin is organic solvent type lignin derived from switchgrass, and the dosage of the lignin is 5g; the reaction medium is ethanol; the inert gas is nitrogen with the pressure of 2.0MPa; the reaction temperature is 150 ℃; the reaction time is 6h; the reactor stirring speed was 600r/min. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained lignin of the switchgrass is 55.6 percent; the yield to propyl coumarate was 7.5wt.% with a selectivity of 68.1%.
Example 9: ionic liquid propanesulfonic pyridine bisulfate ([ pSPy)]HSO 4 ) Method for preparing ethyl p-coumarate by catalyzing selective depolymerization of bagasse lignin
The present embodiment is different from embodiment 1 in that:
the ionic liquid catalyst is propanesulfonic pyridine bisulfate ([ pSPy [ ]]HSO 4 ) (ii) a The using amount of the catalyst is 5mmol; the adopted lignin is organic solvent type lignin derived from bagasse, and the dosage of the lignin is 5g; the reaction medium is ethanol; the inert gas is divided into nitrogen with the pressure of 0.5MPa; the reaction temperature is 150 ℃; the reaction time is 6h; the stirring speed of the reactor is 600r/min is the same as the formula (I). The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained bagasse lignin is 54.9%; the yield of propyl p-coumarate was 11.0wt.% with a selectivity of 72.8%.
Example 10: ionic liquid ethylpyridine hydrogen sulfate ([ ePy)]HSO 4 ) Method for preparing ethyl p-coumarate by catalyzing selective depolymerization of bagasse lignin
The present embodiment is different from embodiment 1 in that:
the ionic liquid catalyst is ethylpyridine bisulfate ([ ePy)]HSO 4 ) (ii) a The using amount of the catalyst is 5mmol; the adopted lignin is organic solvent type lignin derived from bagasse, and the dosage of the lignin is 5g; the reaction medium is ethanol; the inert gas is nitrogen with the pressure of 0.5MPa; the reaction temperature is 150 ℃; the reaction time is 6h; the reactor stirring speed was 600r/min. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained bagasse lignin is 48.3 percent; the yield of propyl p-coumarate was 7.6wt.% with a selectivity of 70.9%.
Example 11: ionic liquid 1-propyl-3-methylimidazolium hydrogen sulfate ([ pmim [ ]]HSO 4 ) Method for preparing p-coumaric acid methyl ester by catalyzing selective depolymerization of bagasse lignin
The present embodiment is different from embodiment 1 in that:
the ionic liquid catalyst used was 1-propyl-3-methylimidazolium hydrogen sulfate ([ pmim [ ]]HSO 4 ) (ii) a The dosage of the catalyst is 8mmol; the adopted lignin is organic solvent type lignin derived from bagasse, and the dosage of the lignin is 5g; the reaction medium is methanol; the inert gas is argon, and the pressure is 0.5MPa; the reaction temperature is 150 ℃; the reaction time is 6h; the reactor stirring speed was 600r/min. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained bagasse lignin is 49.8%; the yield of p-coumaric acid methyl ester was 6.9wt.%, and the selectivity was 70.4%.
Example 12: ionic liquid tetrabutylammonium hydrogen sulfate ([ b ] 4 N]HSO 4 ) Preparation pair for catalyzing selective depolymerization of bagasse ligninCoumaric acid methyl ester
The present embodiment is different from embodiment 1 in that:
the ionic liquid catalyst used was tetrabutylammonium bisulfate ([ b) 4 N]HSO 4 ) (ii) a The dosage of the catalyst is 10mmol; the adopted lignin is organic solvent type lignin derived from bagasse, and the dosage of the lignin is 5g; the reaction medium is methanol; the inert gas is argon, and the pressure is 2.0MPa; the reaction temperature is 150 ℃; the reaction time is 6h; the reactor stirring speed was 600r/min. The test methods and product characterization methods were the same as in example 1.
The depolymerization rate of the obtained bagasse lignin is 50.6%; the yield of p-coumaric acid methyl ester was 7.3wt.%, and the selectivity was 69.8%.
Example 13: ionic liquid 1-butanesulfonic acid group-3-methylimidazole hydrogen sulfate ([ bSmim [ ])]HSO 4 ) Reuse performance of
The ionic liquid catalyst [ bSmim ] used in example 1 was added]HSO 4 Separating the mixture after reaction by adopting a dichloromethane extraction mode, removing an extractant dichloromethane by rotary evaporation at the temperature of 50 ℃, and drying in a vacuum drying oven at the constant temperature of 100 ℃ for 24 hours. The resulting ionic liquid catalyst was subjected to a recycle experiment as described in example 1. The test shows that: the catalyst still shows good catalytic activity after repeating experiments for 10 times, the conversion rate of bagasse lignin can still reach more than 55%, and the mass yield and selectivity of methyl coumarate can still respectively reach 10.9wt.% and 69.8% (figure 6).
The embodiment shows that the method for preparing p-coumaric acid methyl ester by selective conversion of lignin catalyzed by ionic liquid based on the ester exchange principle has the advantages of high catalyst activity, reusability and no need of adding heavy metal ions and halogen ions; the lignin conversion process has the advantages of simple flow, mild conditions, capability of realizing intermittent and continuous reactions and the like.
The embodiments of the present invention are not limited to the above-described embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and they are included in the scope of the present invention.
Claims (10)
1. A method for preparing p-coumarate by catalyzing lignin depolymerization through ionic liquid is characterized by comprising the following steps: taking herbal lignin as a raw material, taking acidic functionalized ionic liquid as a catalyst, taking low-carbon alcohol as a reaction medium, and carrying out ester exchange under the conditions of 0.5-2.0 MPa pressure, 110-180 ℃ and inert atmosphere to obtain coumarate; the acidic functionalized ionic liquid is one of alkyl imidazole hydrogen sulfate, sulfoalkyl imidazole hydrogen sulfate, alkyl pyridine hydrogen sulfate, sulfoalkyl pyridine hydrogen sulfate, alkyl quaternary ammonium hydrogen sulfate and sulfoalkyl quaternary ammonium hydrogen sulfate.
2. The method for preparing p-coumarate by ionic liquid catalyzed lignin depolymerization according to claim 1, wherein: the acidic functionalized ionic liquid is one of the following structural formulas:
3. the method for preparing p-coumarate by depolymerizing lignin catalyzed by ionic liquid according to claim 1, wherein: the lignin is organic solvent type herbaceous lignin.
4. The method for preparing p-coumarate by depolymerizing lignin catalyzed by ionic liquid according to claim 3, wherein: the biomass of the organic solvent type herbaceous lignin is derived from one of corncobs, straws, wheat straws, corn straws, sorghum straws, bagasse, miscanthus, pennisetum and switchgrass.
5. The method for preparing p-coumarate by ionic liquid catalyzed lignin depolymerization according to claim 1, wherein: the lower alcohol is one or more of methanol, ethanol, propanol and isopropanol.
6. The method for preparing p-coumarate by depolymerizing lignin catalyzed by ionic liquid according to claim 1, wherein: the gas of the inert atmosphere is one of nitrogen, argon and helium.
7. The method for preparing p-coumarate by depolymerizing lignin catalyzed by ionic liquid according to claim 1, wherein: the reaction time of the ester exchange is 1 to 6 hours; the transesterification reaction is carried out in a rotating reactor, the rotating speed of which is 400-700 r/min.
8. The method for preparing p-coumarate by depolymerizing lignin catalyzed by ionic liquid according to claim 1, wherein: the dosage of the acidic functionalized ionic liquid is 0.05-2.5 mol/kg lignin; the volume-mass ratio of the reaction medium to the lignin is 5-25, wherein the volume unit is milliliter and the mass unit is gram.
9. The method for preparing p-coumarate by depolymerizing lignin catalyzed by ionic liquid according to claim 1, wherein: the method is characterized in that the method also comprises a purification process after the coumarate is obtained through ester exchange, wherein the purification process is column separation, and eluent obtained through the column separation is a mixture of 1:1 to 3 of mixed solution of petroleum ether and ethyl acetate.
10. The method for preparing p-coumarate by ionic liquid catalyzed lignin depolymerization according to claim 1, wherein: the acidic functionalized ionic liquid is repeatedly used; the repeatedly used acidic functionalized ionic liquid is extracted by dichloromethane, the extractant is removed by rotary evaporation, and then the acidic functionalized ionic liquid is dried in a vacuum drying oven for 6 to 12 hours to obtain the ionic liquid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111529145.7A CN114292185B (en) | 2021-12-14 | 2021-12-14 | Method for preparing p-coumaric acid ester by catalyzing lignin depolymerization through ionic liquid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111529145.7A CN114292185B (en) | 2021-12-14 | 2021-12-14 | Method for preparing p-coumaric acid ester by catalyzing lignin depolymerization through ionic liquid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114292185A CN114292185A (en) | 2022-04-08 |
| CN114292185B true CN114292185B (en) | 2022-12-06 |
Family
ID=80968040
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111529145.7A Active CN114292185B (en) | 2021-12-14 | 2021-12-14 | Method for preparing p-coumaric acid ester by catalyzing lignin depolymerization through ionic liquid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114292185B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106478562A (en) * | 2016-09-14 | 2017-03-08 | 华南理工大学 | A kind of method using ionic liquid-catalyzed living beings full constituent depolymerization |
| CN107602383A (en) * | 2017-08-31 | 2018-01-19 | 华南理工大学 | A kind of method that p-Coumaric Acid ester is prepared using ionic liquid-catalyzed lignin |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180030554A1 (en) * | 2011-09-09 | 2018-02-01 | Hyrax Energy, Inc. | Biomass processing using ionic liquids |
-
2021
- 2021-12-14 CN CN202111529145.7A patent/CN114292185B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106478562A (en) * | 2016-09-14 | 2017-03-08 | 华南理工大学 | A kind of method using ionic liquid-catalyzed living beings full constituent depolymerization |
| CN107602383A (en) * | 2017-08-31 | 2018-01-19 | 华南理工大学 | A kind of method that p-Coumaric Acid ester is prepared using ionic liquid-catalyzed lignin |
Non-Patent Citations (2)
| Title |
|---|
| Catalytic degradation of lignin model compounds in acidic imidazolium based ionic liquids: Hammett acidity and anion effects;Blair J. Cox et al.;《Polymer Degradation and Stability》;20110430(第96期);第426-431页 * |
| Structural changes in lignins isolated using an acidic ionic liquid water mixture;Agnieszka Brandt et al.;《Green Chem.》;20150902;第17卷;第5019-5034页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114292185A (en) | 2022-04-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6989985B2 (en) | A method for preparing a parahydroxycinnamic acid ester using catalytic depolymerization of lignin in an ionic liquid. | |
| Feng et al. | In situ catalytic hydrogenation of model compounds and biomass-derived phenolic compounds for bio-oil upgrading | |
| CN103073395B (en) | Technology for preparing micro-molecular phenolic compound through microwave reinforced continuous degradation of lignin in hydrogen donor | |
| CN112044450B (en) | Acid-base bifunctional biomass carbon-based catalyst and preparation method thereof | |
| CN105753700A (en) | Method of synthesizing methyl acetate through acetylene carbonylation | |
| CN109535109A (en) | A kind of method that the liquefaction of wood fibre orientation prepares 5 hydroxymethyl furfural | |
| CN112094187B (en) | Method for preparing and separating levulinic acid from fructose | |
| CN110511116B (en) | Method for preparing platform compound by full-component depolymerization of primary biomass at interface of two-phase system | |
| CN1939953A (en) | Microwave synthesis for producing polyketone ionic liquid | |
| CN114292185B (en) | Method for preparing p-coumaric acid ester by catalyzing lignin depolymerization through ionic liquid | |
| CN112028861B (en) | Method for preparing furfural by catalyzing corncob | |
| CN113512030A (en) | Aldehyde group protection method of biomass-based furan compound | |
| CN110790651B (en) | Method for continuously producing 3-methyl-3-pentene-2-ketone by using microchannel reactor | |
| CN104829559A (en) | Method of preparing Nu-valerolactone from methyl levulinate | |
| CN109294614B (en) | Method for preparing alkane from lignin derivative in ionic liquid system | |
| CN103159625A (en) | Method of producing trimethylolpropane oleate with single kettle | |
| CN101195600A (en) | Method for producing 4-hydroxyindole | |
| CN110437182B (en) | Method for synthesizing bis (5-methylfuran-2-yl) methane BMFM from 5-methylfurfuryl alcohol 5-MFA | |
| CN108047172B (en) | Method for preparing 2-methyl-5, gamma-dioxotetrahydrofuran-2-pentanoic acid by catalyzing levulinic acid | |
| CN112279826A (en) | Method for preparing and separating 5-hydroxymethylfurfural from fructose | |
| CN109438398A (en) | A method of gamma-valerolactone is prepared by levulic acid | |
| CN113136240B (en) | Method for selectively preparing C5-C6 liquid alkane from cellulose biomass raw material through aqueous phase catalytic conversion | |
| CN114230429B (en) | Method for synthesizing methyl cyclopentadiene from 3-hydroxymethyl cyclopentanone | |
| CN110759819B (en) | 4-methyl-4-phenyl cyclopentenone compound and preparation method thereof | |
| CN109369357B (en) | Method for preparing symmetrical diaryl ketone by catalytic oxidation carbonylation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |