CN111434657B - Preparation method of gamma-valerolactone and levulinate ester compound - Google Patents

Abstract

The invention discloses a preparation method of gamma-valerolactone and levulinate ester compounds. The preparation method of the gamma-valerolactone comprises the following steps of reacting furfural with secondary alcohol under the action of a catalyst to obtain the gamma-valerolactone, wherein the catalyst is M (R) n, M is selected from Ce, sc, Y, yb or Lu, and R is selected from trifluoromethane sulfonic acid group, perfluorobutane sulfonic acid group, heptadecafluoro octane sulfonic acid group, di (trifluoromethane sulfonyl) amino group or di (perfluorobutane sulfonyl) amino group. The method utilizes the commercialized single Lewis acid as the catalyst, avoids the step-by-step and complex product separation process in the traditional gamma-valerolactone preparation process, is simple and efficient, realizes the low-cost production of gamma-valerolactone, and particularly can realize the one-step conversion of biomass (such as xylose, xylan, corncob and the like) into gamma-valerolactone by utilizing the commercialized single catalyst.

Description

A kind of preparation method of gamma-valerolactone and levulinate compound

technical field

The invention relates to a preparation method of gamma-valerolactone and levulinic acid ester compounds.

Background technique

The non-renewability of fossil energy and the environmental degradation effect brought about by the use process force people to re-examine and adjust the long-term development strategy of fossil energy. Future energy development will move towards diversification. Solar energy, wind energy, water energy, tidal energy, biomass energy, nuclear energy, etc. will develop together. There will not be a situation in which one energy dominates in the past, and the specific energy acquisition method will depend on the region. For example, if Tibet is rich in solar energy, it should focus on developing solar energy, and in Northeast China, if it is rich in biomass energy, it should focus on biomass energy. Among all clean energy sources, biomass energy is the only carbon-containing energy source, and has an irreplaceable position in the preparation of fuels and chemicals. my country's medium and long-term development plan has made the development and utilization of biomass resources a strategic focus of sustainable development. Lignocellulose is transformed from green plants through photosynthesis. It has a wide range of sources and is cheap. It is a non-food renewable biomass resource. The world produces about 17 billion tons of lignocellulose through photosynthesis every year, which has great potential for development.

At present, great progress has been made in the research on biomass in the world. Hundreds of small molecule platform products can be obtained through "biomass refining". In 2004, the US Department of Energy announced a list of high value-added chemicals (derived from biomass Chemicals) report, which proposed twelve important platform products: succinic acid, 2,5-furandicarboxylic acid, aspartic acid, glutamic acid, itaconic acid, 3-hydroxypropionic acid, glucose di acid, levulinic acid, glycerol, xylitol and sorbitol (Green Chemistry, 2015, 17(2):959-972). However, considering the cost of raw materials, production cost, environmental cost, market size and price, technical feasibility and other issues, currently, only a handful of refined biomass products have entered the market, and all of them are refined products of food crops. The most typical is bioethanol. According to statistics, as of 2007, China has become the third largest producer of bioethanol after the United States and Brazil (Renewable and Sustainable Energy Reviews, 2009, 13(9):2571-2579). Most of the current bioethanol uses edible biomass such as corn, starch, and syrup as raw materials. This approach solves the energy problem to a certain extent in the short term, but solving the energy problem at the expense of food will inevitably lead to new problems. Therefore, using non-edible lignocellulose such as crop straws to replace food to solve energy problems is the future trend of biomass energy development. Statistics show that, as a large agricultural country, China produces 400 million tons of crop waste (straw, rice husk, etc.) every year (Green Chemistry, 2013, 15(3): 584). And the annual crop waste in the United States can reach 1.3 billion tons (G.W. Huber, NSF, DOE, and American Chemical Society Workshop, Washington, DC, 2007).

Lignocellulose is rich in hemicellulose resources. Hemicellulose has the characteristics of low degree of polymerization and high degree of branching, and is relatively easy to degrade. The xylose unit in it is easily dehydrated and converted into furfural under the catalysis of protonic acid. As early as the 1930s, the use of crop straw and hemicellulose in corncobs to prepare furfural had reached an industrial scale (Nature, 2016, 531(7593): 215-219). According to data, at present, my country is rich in furfural resources and is the largest furfural producer in the world, accounting for 70% of the world's annual furfural production (Energy Environ Sci, 2016, 9(4): 1144-1189). As the only fine chemical product that is produced on an industrial scale from non-edible biomass resources, furfural provides an example for sustainable and renewable chemical development in the new era. However, due to the limitations of key issues such as high production costs and low profits, a large-scale renewable chemical product industry chain with furfural as the core has not been formed in the past 100 years of industrial production of furfural.

Among the many downstream products of furfural, γ-valerolactone is a fine chemical product with high added value and high economic value. Its market price is US$ 35,484 per ton, which is 30 times the price of furfural (Journal of Industrial and Engineering Chemistry, 2017, 48, 173-179). In 2010, James A. Dumesic used γ-valerolactone as raw material to directly prepare transportation fuel (Science, 2010, 322, 417-421). Subsequently, in 2014, the James A. Dumesic team found that γ-valerolactone is a good green biomass solvent with a high boiling point (207-208 ° C), miscibility with water in any ratio, and low toxicity (its The half lethal dose is less than ethanol), they used γ-valerolactone mixed with water as a solvent to degrade natural biomass such as rice husk and cork, and achieved a monosaccharide yield of 90% (Science, 2014, 343, 277-280). The use of furfural as raw material to prepare fine chemical product γ-valerolactone will surely make up for the economic disadvantages of furfural production and provide an opportunity for the development of a large-scale renewable chemical product industry chain with furfural as the core.

At present, the production of γ-valerolactone from furfural as a starting material still has a large bottleneck in technology and production route. The preparation of γ-valerolactone from furfural usually requires a process of at least three steps, and its synthetic route is as follows:

First, furfural is reduced to furfuryl alcohol, and then furfural alcohol is hydrolyzed under acid catalysis to generate levulinic acid or levulinic acid ester, and finally, the obtained levulinic acid compounds undergo reductive ring closure to generate the final γ-valerolactone.

In 1937, Du Pont de Nemours improved the gas phase production method of furfuryl alcohol, and then Quaker Oats used _Na2O · _xSiO2 supported copper catalyst to catalyze the reduction of furfural at a temperature of 405-450K, A yield of 99% was achieved. Today, the conversion of furfural to furfuryl alcohol has reached a commercial scale, and 65% of furfural in the world is used to produce furfuryl alcohol every year (Furfural and Derivatives, WileyVCH Verlag GmbH & Co. KGaA, Weinheim, 2012.). Currently, the conversion process of levulinic acid/levulinate to γ-valerolactone has also achieved high yields. In 2009, Fu Yao's research team used formic acid to catalyze ruthenium trichloride in situ cracking and hydrogenation reduction of levulinic acid to prepare γ-valerolactone with a yield of 95% (Angew.Chem.Int.Ed.2009,48, 6529–6532); in 2015, Han Buxing’s research group obtained 97% yield of γ-valerolactone by using zirconium phytate catalyst to reduce levulinic acid in sec-butanol (Angew.Chem.Int.Ed.2015,54,9399 –9403.). These methods avoid the safety problems caused by the use of hydrogen in the traditional reduction process, solve the most important problem in the reduction reaction of organic matter at present, and replace the traditional hydrogen with a safe and efficient hydrogen carrier and release delivery system.

Currently, the hydrolysis/alcoholysis process from furfuryl alcohol to levulinic acid/levulinate is a key step that affects the yield of the whole process. Usually, furfuryl alcohol undergoes hydrolysis/alcoholysis reaction under acidic conditions, accompanied by some side reactions such as: oxidation, polymerization, etc., resulting in insoluble brown oligomer Humit (Journal of Industrial and Engineering Chemistry, 2014, 20, 650–655 ). In 2009, Lange's research group used H-ZSM-5, Amberlyst and Dowex series resins to catalyze the alcoholysis of furfuryl alcohol to generate levulinate, achieving a high yield of 90% (ChemSusChem, 2009, 2, 437–441). In 2015, Fu Yao's research group at the University of Science and Technology of China found that aluminum sulfate was used as a catalyst to react under microwave conditions to obtain a yield of 80.6% of methyl levulinate (Green Chem., 2016, 18, 1516-1523) .

acid)及Zr-Beta(Lewis acid)结合以仲丁醇作为氢源实现了糠醛到γ-GVL的一锅转化，得到了78％的γ-戊内酯收率(Angew.Chem.Int.Ed.2013,52,8022–8025)，避免了三步反应带来的繁琐的分离提纯过程，但仍存在催化体系复杂，催化剂制备条件苛刻的问题。Although the three single-step reactions have achieved relatively high yields, the final yield of the entire production route is still unsatisfactory (74%). At the same time, cumbersome production steps and complex catalytic systems have brought about difficult separation processes , increasing the energy and economic consumption in the production process. It has brought huge obstacles to the industrialization of this process. In 2013, the Yuriy Román-Leshkov research group at Cambridge University used Al-MFI-n(

acid) and Zr-Beta (Lewis acid) combined with sec-butanol as a hydrogen source to realize the one-pot conversion of furfural to γ-GVL, and obtained 78% γ-valerolactone yield (Angew.Chem.Int.Ed .2013,52,8022–8025), avoiding the tedious separation and purification process brought about by the three-step reaction, but there are still problems of complex catalytic system and harsh catalyst preparation conditions.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the defects of complex production process, low efficiency and complicated separation process of gamma-valerolactone and levulinic acid ester compounds in the prior art, and provide a kind of gamma-valerolactone and The preparation method of levulinic acid ester compound. The preparation method of the present invention is simple, efficient and has no cumbersome separation process. In particular, the commercialized single catalyst can be used in the present invention to realize the one-step conversion of biomass (such as xylose, xylan and corn cob, etc.) into γ-pentane ester.

In order to achieve the above object, the present invention adopts the following technical solutions.

The invention provides a preparation method of gamma-valerolactone, which comprises the following steps of reacting furfural and secondary alcohol under the action of a catalyst to prepare gamma-valerolactone;

The catalyst is M(R)n, wherein M is selected from Ce, Sc, Y, Yb or Lu, and R is selected from trifluoromethanesulfonate (OTf), perfluorobutanesulfonate (ONf), heptadecafluoro Octanesulfonate (OPf), bis(trifluoromethanesulfonyl)amino (NTf ₂ ) or bis(perfluorobutanesulfonyl)amino (NNf ₂ );

In the present invention, said M is preferably Sc.

In the present invention, the R is preferably trifluoromethanesulfonate (OTf) or perfluorobutanesulfonate (ONf).

In the present invention, the value of n in the M(R)n can be determined according to the number of ligands R to which M can bind, and should generally be a positive integer.

In the present invention, the catalyst is preferably Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ , Lu(OTf) ₃ , Sc(OPf) ₃ , Sc(NTf ₂ ) ₃ and Sc(NNf ₂ ) ₃ , such as Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf ) ₃ , Lu(OTf) ₃ , Sc(OPf) ₃ , Sc(NTf ₂ ) ₃ or Sc(NNf ₂ ) ₃ .

Wherein, _the structural formula of the Sc(OTf) is as follows:

Wherein, the structural formula of _the Sc(ONf) is as follows:

Wherein, the structural formula of _the Sc(OPf) is as follows:

Wherein, the structural formula of the Sc(NTf ₂ ) ₃ is as follows:

Wherein, the structural formula of the Sc(NNf ₂ ) ₃ is as follows:

In the present invention, the molar ratio of the catalyst to the furfural is preferably (0.1-100):100, more preferably (1-10):100, for example 5:100.

In the present invention, the secondary alcohol refers to an alcohol with two carbons (or substituents) attached to the carbon where the hydroxyl group (-OH) is located (ie, the hydroxyl carbon), and its structural formula is R'-CH(R")-OH. The secondary alcohol may be selected from C ₃ -C ₁₀ secondary alcohols, preferably C ₃ -C ₆ secondary alcohols, such as isopropanol.

In the present invention, preferably, the secondary alcohol can participate in the reaction as a solvent and a reactant.

In the present invention, the reaction can also be carried out in an inert solvent.

Wherein, the inert solvent can be a conventional inert solvent in the art, and generally refers to a solvent that does not react with catalysts and reactants (such as furfural and secondary alcohols), such as hexane, benzene, carbon tetrachloride and ethyl dichloride. One or more of alkanes.

When the reaction is carried out in an inert solvent, the secondary alcohol can participate in the reaction as a solvent and a reactant, or only as a reactant.

In the present invention, the volume (mL) of the secondary alcohol and the molar (mmol) ratio of the furfural are preferably 3:(0.01～1), more preferably 3:(0.05～0.5), for example 3:0.05, 3 :0.1, 3:0.125, 3:0.25 or 3:0.5.

In the present invention, the reaction temperature may be a conventional reaction temperature in the art, preferably 100-200°C, such as 140-170°C, further for example 140°C, 150°C or 170°C.

In the present invention, the reaction time may be a conventional reaction time in the art, preferably 6-48 hours, such as 24-48 hours, further such as 24 hours, 36 hours or 48 hours.

When the catalyzer is Sc(ONf) ₃ , the mol ratio of the catalyzer and the furfural is preferably (1～10):100 (such as 5:100), the volume (mL) of the secondary alcohol and the The molar (mmol) ratio of furfural is preferably 3:(0.05-0.5) (eg 3:0.05), the temperature of the reaction is preferably 140-170°C (eg 150°C), and the reaction time is preferably 24-36h (eg 36h).

When the catalyzer is Sc(OTf) ₃ , the mol ratio of the catalyzer and the furfural is preferably (1～10):100 (such as 5:100), the volume (mL) of the secondary alcohol and the The molar (mmol) ratio of furfural is preferably 3:(0.05～0.5) (such as 3:0.05, 3:0.1, 3:0.125, 3:0.25 or 3:0.5), and the reaction temperature is preferably 140～170°C (eg 140°C, 150°C or 170°C), the reaction time is preferably 24-36h (eg 24h or 36h).

When the catalyzer is Y(OTf) ₃ , the mol ratio of the catalyzer and the furfural is preferably (1～10): 100 (eg 5:100), the volume (mL) of the secondary alcohol and the The molar (mmol) ratio of furfural is preferably 3:(0.05-0.5) (eg 3:0.05), the temperature of the reaction is preferably 140-170°C (eg 150°C), and the reaction time is preferably 24-36h (eg 36h).

When the catalyzer is Yb(OTf) ₃ , the mol ratio of the catalyzer and the furfural is preferably (1～10): 100 (for example 5:100), the volume (mL) of the secondary alcohol and the The molar (mmol) ratio of furfural is preferably 3:(0.05-0.5) (eg 3:0.05), the temperature of the reaction is preferably 140-170°C (eg 150°C), and the reaction time is preferably 24-36h (eg 36h).

When the catalyzer is Lu(OTf) ₃ , the mol ratio of the catalyzer and the furfural is preferably (1～10): 100 (eg 5:100), the volume (mL) of the secondary alcohol and the The molar (mmol) ratio of furfural is preferably 3:(0.05-0.5) (eg 3:0.05), the temperature of the reaction is preferably 140-170°C (eg 150°C), and the reaction time is preferably 24-36h (eg 36h).

When the catalyzer is Ce(OTf) ₃ , the mol ratio of the catalyzer and the furfural is preferably (1～10):100 (such as 5:100), the volume (mL) of the secondary alcohol and the The molar (mmol) ratio of furfural is preferably 3:(0.05-0.5) (eg 3:0.05), the temperature of the reaction is preferably 140-170°C (eg 150°C), and the reaction time is preferably 24-36h (eg 36h).

In the present invention, after the γ-valerolactone is produced, the catalyst can be recycled after conventional regeneration treatment in the field, for example, after vacuum distillation to separate γ-valerolactone, secondary alcohol and by-products, the catalyst is dried, It can be recycled.

In the present invention, in the process of preparing gamma-valerolactone from furfural, ketones are the only by-products in the preparation process, and the separation is simple, which is beneficial to realize the industrial production of gamma-valerolactone. For example, when the secondary alcohol is isopropanol, the only by-product is acetone.

In the present invention, during the process of generating γ-valerolactone from furfural, the intermediate products generally include furfuryl alcohol and levulinic acid ester compounds.

The present invention also provides a preparation method of γ-valerolactone, which includes the following steps, under the action of a catalyst, reacting furfuryl alcohol and secondary alcohol to obtain γ-valerolactone; as defined above;

Wherein, the molar ratio of the catalyst to the furfuryl alcohol is preferably (0.1-100):100, more preferably (1-10):100, for example 5:100.

Wherein, the definition of the secondary alcohol is as described above.

Wherein, preferably, the secondary alcohol participates in the reaction as a solvent and a reactant.

Wherein, the reaction can also be carried out in an inert solvent. The definition of the inert solvent is as mentioned above.

When the reaction is carried out in an inert solvent, the secondary alcohol can participate in the reaction as a solvent and a reactant, or only as a reactant.

Wherein, the volume (mL) of the secondary alcohol and the molar (mmol) ratio of the furfuryl alcohol are preferably 3:(0.01-1), more preferably 3:(0.05-0.5), for example 3:0.125.

Wherein, the reaction temperature may be a conventional reaction temperature in the art, preferably 100-200°C, such as 140-170°C, and for example 150°C.

Wherein, the time of described reaction is as described above. The reaction time may be a conventional reaction time in the art, preferably 6-48 hours, such as 24-48 hours, and for example 36 hours.

When the catalyzer is Sc(OTf) ₃ , the mol ratio of the catalyzer and the furfuryl alcohol is preferably (1～10): 100 (such as 5:100), the volume (mL) of the secondary alcohol and the The molar (mmol) ratio of furfuryl alcohol is preferably 3:(0.05～0.5) (for example 3:0.125), the temperature of the reaction is preferably 140～170°C (for example 150°C), and the reaction time is preferably 24～36h (eg 36h).

The present invention also provides a preparation method of γ-valerolactone, which includes the following steps, under the action of a catalyst, reacting the levulinic acid ester compound shown in formula I with a secondary alcohol to prepare γ-valerolactone Valerolactone, ok;

The catalyst is as defined above;

The R ₁ is H or C ₁ -C ₄ alkyl;

Wherein, the definition of the secondary alcohol is as described above.

Wherein, preferably, the secondary alcohol participates in the reaction as a solvent and a reactant.

Wherein, the reaction can also be carried out in an inert solvent. The definition of the inert solvent is as mentioned above.

When the reaction is carried out in an inert solvent, the secondary alcohol can participate in the reaction as a solvent and a reactant, or only as a reactant.

Wherein, the C ₁ -C ₄ alkyl group may be methyl, ethyl, isopropyl or tert-butyl.

Wherein, the molar ratio of the catalyst to the levulinic acid ester compound shown in formula I is preferably (0.1-100):100, more preferably (1-10):100, for example 5:100 or 10 :100.

Wherein, the volume (mL) of the secondary alcohol and the molar (mmol) ratio of the levulinate compound shown in formula I are preferably 3:(0.01～1), more preferably 3:(0.05～ 0.5), for example 3:0.5.

Wherein, the reaction temperature may be a conventional reaction temperature in the art, preferably 100-200°C, such as 140-170°C, and for example 150°C.

Wherein, the reaction time may be a conventional reaction time in the art, preferably 6-48 hours, such as 24-48 hours, and for example 24 hours.

When the catalyst is Sc(OTf) ₃ , and the R ₁ is H, the molar ratio of the catalyst to levulinic acid is preferably (1-10):100 (for example, 10:100), and the secondary alcohol The volume (mL) of levulinic acid and the molar (mmol) ratio of levulinic acid are preferably 3:(0.05～0.5) (for example 3:0.5), the temperature of described reaction is preferably 140～170 ℃ (for example 150 ℃), the described The reaction time is preferably 24-36 hours (for example, 24 hours).

When the catalyst is Sc(OTf) ₃ , and the R ₁ is a C ₁ -C ₄ alkyl group, the molar ratio of the catalyst to the levulinic acid ester compound shown in formula I is preferably (1～10):100 (such as 5:100), the volume (mL) of described secondary alcohol and the molar (mmol) ratio of described levulinic acid ester compound shown in formula I are preferably 3:(0.05 ~0.5) (eg 3:0.5), the temperature of the reaction is preferably 140-170°C (eg 150°C), and the reaction time is preferably 24-36h (eg 24h).

The present invention also provides a preparation method of levulinic acid ester compounds shown in formula II, which includes the following steps, under the action of a catalyst, furfuryl ether compounds shown in formula III, water and non- The aliphatic alcohol of secondary alcohol is reacted, and the levulinate compound as shown in formula II is obtained, and gets final product;

The equivalent ratio of the furfuryl ether compound to the water is 1: (1-5);

The catalyst is M ¹ (R ¹ )n ¹ , wherein M ¹ is selected from Ce, Sc, Y, Yb or Lu, and R ¹ is selected from trifluoromethanesulfonate, perfluorobutanesulfonate, heptadecafluorooctyl Alkanesulfonic acid group, bis(trifluoromethanesulfonyl)amine group or bis(perfluorobutanesulfonyl)amine group;

The R ₃ is a C ₁ -C ₄ alkyl group;

Said _R is the aliphatic moiety of said non-secondary alcohol aliphatic alcohol.

Wherein, the value of n ^{1 in} M ¹ (R ¹ )n 1 can be determined according to the number of ligands R ¹ that M ¹ can bind to, and should generally be a positive integer.

Wherein, the M ¹ is preferably Sc.

Wherein, the R ¹ is preferably a trifluoromethanesulfonate group or a perfluorobutanesulfonate group.

Among them, the catalyst is preferably Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ and Lu(OTf) ₃ , Sc(OPf) ₃ , Sc One or more of (NTf ₂ ) ₃ and Sc(NNf ₂ ) ₃ , such as Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ , Lu(OTf) ₃ , Sc(OPf) ₃ , Sc(NTf ₂ ) ₃ or Sc(NNf ₂ ) ₃ .

Wherein, the R ₃ can be a C ₁ , C ₂ or C ₄ alkyl group, such as methyl, ethyl or tert-butyl.

Wherein, the molar ratio of the furfuryl ether compound to the water is preferably 1:5 or 1:1, more preferably 1:1.

Wherein, the molar ratio of the catalyst to the furfuryl ether compound represented by formula III is preferably (0.1-100):100, more preferably (1-10):100, for example 5:100.

Wherein, the non-secondary alcohol fatty alcohol is preferably one or more of methanol, ethanol and C ₃ -C ₁₀ non-secondary alcohol fatty alcohol, such as one or more of methanol, ethanol and tert-butanol species, such as methanol, ethanol or tert-butanol.

When the aliphatic alcohol other than secondary alcohol is methanol, the R ₂ is methyl.

When the fatty alcohol other than secondary alcohol is ethanol, the R ₂ is ethyl.

When the fatty alcohol other than secondary alcohol is tert-butanol, the R ₂ is tert-butyl.

Wherein, preferably, the fatty alcohol other than secondary alcohol participates in the reaction as a solvent and a reactant.

Wherein, the reaction can also be carried out in an inert solvent. The definition of the inert solvent is as mentioned above.

When the reaction is carried out in an inert solvent, the non-secondary alcohol aliphatic alcohol can participate in the reaction as a solvent and a reactant, or only as a reactant.

Wherein, the molar (mmol) ratio of the volume (mL) of the fatty alcohol of the non-secondary alcohol to the furfuryl ether compound shown in formula III is preferably 3:(0.01～1), more preferably 3: (0.1～1), such as 3:0.5.

Wherein, the reaction temperature may be a conventional reaction temperature in the art, preferably 100-200°C, for example, 100°C.

Wherein, the reaction time may be a conventional reaction time in the art, preferably 6-48 hours, such as 12 hours.

Wherein, in the preparation method of the levulinic acid ester compound shown in formula II, the following steps may also be included: under the action of a catalyst, react furfuryl alcohol and fatty alcohol other than secondary alcohol to prepare the formula III The furfuryl ether compounds shown can be;

The catalyst is M ¹ (R ¹ )n ¹ , which is as defined above;

The R ₃ is defined as previously described;

The molar ratio of the catalyst to the furfuryl alcohol is preferably (0.1-100):100, more preferably (1-10):100, for example 5:100.

The ratio of the volume (mL) of the non-secondary fatty alcohol to the molar (mmol) ratio of the furfuryl alcohol is preferably 3:(0.125-0.5), for example 3:0.125 or 3:0.5.

The present invention also provides a method for preparing levulinic acid ester compounds as shown in formula II, which includes the following steps, under the action of a catalyst, reacting furfuryl alcohol with fatty alcohols other than secondary alcohols to prepare the formula The levulinic acid ester compounds shown in II can be;

The catalyst is M ¹ (R ¹ )n ¹ , which is as defined above;

The definition of _R2 is as previously described;

Among them, the catalyst is preferably Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ and Lu(OTf) ₃ , Sc(OPf) ₃ , Sc One or more of (NTf ₂ ) ₃ and Sc(NNf ₂ ) ₃ , such as Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ , Lu(OTf) ₃ , Sc(OPf) ₃ , Sc(NTf ₂ ) ₃ or Sc(NNf ₂ ) ₃ .

Wherein, the molar ratio of the catalyst to the furfuryl alcohol is preferably (0.1-100):100, more preferably (1-10):100, for example 5:100.

Wherein, the non-secondary alcohol fatty alcohol is preferably one or more of methanol, ethanol and C ₃ -C ₁₀ non-secondary alcohol fatty alcohol, such as one or more of methanol, ethanol and tert-butanol species, such as methanol, ethanol or tert-butanol.

Wherein, preferably, the fatty alcohol other than secondary alcohol participates in the reaction as a solvent and a reactant.

Wherein, the reaction can also be carried out in an inert solvent. The definition of the inert solvent is as mentioned above.

When the reaction is carried out in an inert solvent, the non-secondary alcohol aliphatic alcohol can participate in the reaction as a solvent and a reactant, or only as a reactant.

Wherein, the volume (mL) of the fatty alcohol of the non-secondary alcohol and the molar (mmol) ratio of the furfuryl alcohol compound are preferably 3:(0.01～1), more preferably 3:(0.05～0.5), for example 3: 0.5.

Wherein, the reaction temperature may be a conventional reaction temperature in the art, preferably 100-200°C, for example, 100°C.

Wherein, the reaction time may be a conventional reaction time in the art, preferably 6-48 hours, such as 12 hours.

When the catalyst is Sc(OTf) ₃ , and the non-secondary alcohol fatty alcohol is methanol, ethanol or tert-butanol, the molar ratio of the catalyst to the furfuryl alcohol is preferably (1-10):100 (for example 5:100), the volume (mL) of the fatty alcohol of described non-secondary alcohol and the molar (mmol) ratio of described furfuryl alcohol are preferably 3:(0.05～0.5) (for example 3:0.5), described reaction The temperature is preferably 100-200°C (eg 100°C), and the reaction time is preferably 6-48h (eg 12h).

The present invention also provides a preparation method of gamma-valerolactone, which comprises the following steps of reacting xylose-type biomass and secondary alcohol under the action of a catalyst to prepare gamma-valerolactone;

The catalyst is M ¹ (R ¹ )n ¹ , which is as defined above;

In the present invention, the xylose-type biomass generally needs to be ground and dried before being reacted.

Among them, the catalyst is preferably Sc(OTf) ₃ .

Wherein, the xylose-type biomass refers to plant organisms containing xylose structural units formed through photosynthesis, such as corn cobs and/or straws, and for example one of hemicellulose, xylan and xylose one or more species.

The hemicelluloses generally refer to polymers composed of one or several different types of monosaccharides, such as the hemicelluloses composed of xylose units shown in Formula 1:

Described xylose is shown in formula 2:

Wherein, the definition of the secondary alcohol is as described above.

Wherein, preferably, the secondary alcohol participates in the reaction as a solvent and a reactant.

Wherein, the reaction can also be carried out in an inert solvent. The definition of the inert solvent is as mentioned above.

When the reaction is carried out in an inert solvent, the secondary alcohol can participate in the reaction as a solvent and a reactant, or only as a reactant.

Wherein, the molar ratio of the catalyst to the biomass is preferably (0.1-100):100, more preferably (10-30):100, for example 20:100.

Wherein, the volume (mL) of the secondary alcohol and the molar (mmol) ratio of the biomass is preferably 3:(0.001～0.1), more preferably 3:(0.025～0.05), for example 3:0.025 or 3: 0.05.

Wherein, the ratio of the volume (mL) of the secondary alcohol to the mass (mg) of the biomass is preferably 3:(10-100), more preferably 3:(20-50), for example 3:25.

Wherein, the reaction temperature may be a conventional reaction temperature in the art, preferably 150-250°C, such as 170-210°C, and for example 190°C.

Wherein, the reaction time may be a conventional reaction time in the art, preferably 6-48 hours, such as 24-48 hours, further such as 24 hours or 48 hours.

When the biomass is xylose, the catalyst is preferably Sc(OTf) ₃ , the molar ratio of the catalyst to the biomass is preferably 20:100, the volume (mL) of the secondary alcohol and the The molar (mmol) ratio of biomass is preferably 3:0.05, the temperature of the reaction is preferably 190°C, and the reaction time is preferably 24h.

When the biomass is xylan, the catalyst is preferably Sc(OTf) ₃ , the molar ratio of the catalyst to the biomass is preferably 20:100, the volume (mL) of the secondary alcohol and the The molar (mmol) ratio of the biomass is preferably 3:0.05 or 3:0.025, the temperature of the reaction is preferably 190°C, and the reaction time is preferably 24h.

When the biomass is corn cob, the catalyst is preferably Sc(OTf) ₃ , the molar ratio of the catalyst to the biomass is preferably 20:100, the volume (mL) of the secondary alcohol and the The mass (mg) ratio of biomass is preferably 3:25, the temperature of the reaction is preferably 190°C, and the reaction time is preferably 48h.

In the present invention, the catalyst can be immobilized by resin, and the resin can be Nafion resin (purchased from Nanda Synthesis). For example, the catalyst is immobilized by Nafion resin to prepare a catalyst with M-Nafion structure. In the present invention, after the catalyst is immobilized by the resin, it is beneficial to the regeneration of the catalyst, and the regeneration process is simple, convenient and easy to operate.

On the basis of conforming to common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain preferred examples of the present invention.

The reagents and raw materials used in the present invention are all commercially available.

The positive progress effect of the present invention is:

(1) The present invention realizes the direct use of biomass and fine chemical products derived from biomass (such as hemicelluloses, xylose, furfural and furfuryl alcohol, etc.) as raw materials, through dehydration-reduction-ring-opening-isomerization- A series of processes of esterification-reduction-ring closure, one-pot conversion to prepare γ-valerolactone, wherein the yield of γ-valerolactone prepared from furfural can be as high as 95%, and γ-valerolactone prepared from xylose as raw material The yield can reach 53%, and the yield of gamma-valerolactone prepared from xylan can reach 51%.

(2) The present invention utilizes the single Lewis acid of commercialization as catalyst, has avoided step-by-step and complex product separation process in the traditional γ-valerolactone preparation process, is simple and efficient, realizes the low-cost production of γ-valerolactone ;Secondary alcohol can be used as solvent and hydrogen source, avoiding the safety problems caused by the use of hydrogen in the traditional reduction process; the catalyst can be reused, and the separation process is simple (distillation), avoiding the complicated and tedious separation and purification in the previous production routes and technologies The process and catalyst preparation conditions are harsh and the catalytic system is complex.

(3) The present invention utilizes commercialized single Lewis acid as a catalyst to catalyze the preparation of levulinic acid ester compounds, wherein the yield of levulinic acid ester compounds prepared from furfuryl alcohol can be as high as 90%, and furfuryl ether compounds, The yield of levulinate esters prepared from fatty alcohols other than secondary alcohols and water can reach 68%.

(4) In the preparation method of the present invention, gamma-valerolactone can be directly prepared from macromolecular biomass as a raw material, which provides a basis for the development of a large-scale renewable chemical product industry chain centered on biomass such as corncobs opportunity.

Description of drawings

Figure 1 is the ¹ H NMR spectrum of furfural (CDCl ₃ , 500MHz).

Figure 2 is the ¹ H NMR spectrum of furfuryl alcohol (CDCl ₃ , 500MHz).

Fig. 3 is the hydrogen nuclear magnetic spectrum ¹ H NMR (CDCl ₃ , 500MHz) of isopropyl levulinate.

Figure 4 is the ¹ H NMR spectrum of γ-valerolactone (CDCl ₃ , 500MHz).

Fig. 5 is the in situ nuclear magnetic proton spectrum ¹ H NMR (CDCl ₃ , 500MHz) in Example 24.

Fig. 6 is the in situ H NMR spectrum ¹ H NMR (CDCl ₃ , 500MHz) in Example 25.

Fig. 7 is the ¹ H NMR spectrum of Example 26 (CDCl ₃ , 500 MHz).

Fig. 8 is the in-situ carbon NMR spectrum ¹³ C NMR (C ₆ D ₆ , 126 MHz) in Example 27.

Detailed ways

The present invention is further illustrated below by means of examples, but the present invention is not limited to the scope of the examples. For the experimental methods that do not specify specific conditions in the following examples, select according to conventional methods and conditions, or according to the product instructions.

In the following examples, the preparation process was carried out in a pressure-resistant Shrek tube, and the test was performed after cooling to room temperature after the reaction.

In the following examples, the composition of the product was determined by ¹ H NMR, ¹³ C NMR and GC-MS, and the content was tested by GC (Agilent 6890).

Test conditions: Agilent US0769531J (DB-WAX 15m × 0.320mm × 0.25μm) capillary column, flame ionization detector, N2 _carrier gas (2mL/min); temperature program: 60 ° C for 5 minutes); at 5 ° C / Raise the temperature to 70°C at a rate of 1 min (reserve for 10 minutes); raise the temperature to 80°C at a rate of 2°C/min (reserve for 4 minutes); raise the temperature to 200°C at a rate of 5°C/min (reserve for 2 minutes); inlet temperature: 250 °C; detector temperature: 250 °C; injection volume: 10 μL. Using naphthalene as an internal standard, the product content was determined by the internal standard method.

In the following examples and comparative examples: Sc ₂ O ₃ was purchased from Anaiji Pharmaceutical Company, ScCl ₃ 6H ₂ O was purchased from Anaiji Pharmaceutical Company, ScCl ₃ was purchased from Anaiji Pharmaceutical Company, Sc(OTf) ₃ Purchased from Anaiji Pharmaceutical Company, Y(OTf) ₃ was purchased from Anaiji Pharmaceutical Company, Yb(OTf) ₃ was purchased from Anaiji Pharmaceutical Company, Al(OTf) ₃ was purchased from Anaiji Pharmaceutical Company, Al(iPrO ) ₃ was purchased from Bailingwei Pharmaceutical Company, Phy-Zr was prepared by itself, and HOTf was purchased from Bailingwei Pharmaceutical Company.

In the following examples, the preparation method of Sc(ONf) ₃ is: refluxing scandium oxide Sc ₂ O ₃ and perfluorobutanesulfonic acid in water, collecting the solid by filtration, and drying to obtain Sc(ONf) ₃ .

In Example 10, the method of immobilizing the catalyst with Nafion (perfluorosulfonic acid resin) resin is as follows: dissolve ScCl ₃ 6H ₂ O in ethanol, add Nafion resin, fully disperse, add ammonia water, reflux, filter, wash and dry. Can. After the resin is cured, the catalyst is Sc-Nafion (scandium perfluorosulfonate resin).

The preparation of embodiment 1γ-valerolactone

Take a pressure-resistant Shrek tube, add 0.05mmol furfural, 5%mmol Sc(ONf) ₃ , add 3mL isopropanol, stir, react at 150°C for 36h, measure the conversion rate of raw materials and product yield, see Table 1 for details .

Furfural: See Figure 1 for ¹ H NMR (CDCl ₃ , 500 MHz).

Furfuryl alcohol: See Figure 2 for ¹ H NMR (CDCl ₃ , 500 MHz).

Isopropyl levulinate: See Figure 3 for ¹ H NMR (CDCl ₃ , 500 MHz).

γ-valerolactone: See Figure 4 for ¹ H NMR (CDCl ₃ 500MHz).

The preparation method of embodiment 2～22 is the same as embodiment 1. The raw materials, catalyst types and reaction conditions can be seen in Table 1, and the product yield and by-product yield can also be seen in Table 1.

Table 1

Note: "/" means no detection.

Example 23

Take a pressure-resistant Shrek tube, add 250mg corn cob, 20%mmol Sc(OTf) ₃ , add 30mL isopropanol, stir, react at 190°C for 48h, measure the product yield, the yield of γ-valerolactone is 18%.

Can know by embodiment 1～23:

(1) Examples 1 to 6 illustrate that when furfural is used as a raw material, the triflate of cerium, scandium, yttrium, ytterbium and lutetium can directly prepare gamma-valerolactone, indicating that metal scandium and lanthanide metal salts It is suitable for "one-pot" catalysis of furfural to γ-valerolactone; especially, the yield of γ-valerolactone prepared by triflate of scandium, yttrium, ytterbium and lutetium can reach more than 90% , good catalytic effect;

(2) Example 7 illustrates that when using furfuryl alcohol as a raw material, the yield of gamma-valerolactone can reach 92%, indicating that metal scandium and lanthanide metal salts are equally suitable for catalyzing furfuryl alcohol to generate gamma-valerolactone;

(3) Examples 8～9, 22～23 illustrate that when using biomass (xylose, xylan and corn cob) as raw materials, the yield of gamma-valerolactone can reach 53%, indicating that metal scandium and Lanthanide metal salts are also suitable for catalyzing the production of γ-valerolactone from biomass;

(4) Example 10 illustrates that after the catalyst is immobilized by Nafion resin in the application, furfural can still be catalyzed to generate gamma-valerolactone, and its yield is more than 60%, which expands the industrial application mode of the catalyst in the application;

(5) Examples 11 to 14 illustrate that when using levulinic acid ester compounds as raw materials, the yield of gamma-valerolactone can reach more than 90%, indicating that metal scandium and lanthanide metal salts are equally applicable to catalyzing levulinic acid Esters generate γ-valerolactone;

(6) Examples 15 to 18 illustrate that, within a certain range, the prolongation of the reaction time and the raising of the reaction temperature are conducive to promoting the productive rate of gamma-valerolactone; but too high reaction temperature and too long reaction time will On the contrary, it will cause the yield of γ-valerolactone to decrease;

(7) Example 17, 19～21 illustrate, when the ratio of furfural (mmol) and secondary alcohol (mL) is in the scope of (0.1-0.5):3, along with the reduction of furfural concentration, gamma-valerolactone yield increased. The inventors have found through research that in the preparation method of the present application, increasing the concentration of furfural will lead to an increase in side reactions, so in the case of constant total volume, as the concentration of furfural decreases, the yield of γ-valerolactone will increase .

After the reaction in Example 2, the product was separated by distillation, Sc(OTf) ₃ was recovered, washed with dichloromethane, dried and reused. For a catalytic concentration of 0.05mmol/3mL, at 150°C, 36 Under the condition of 1 hour, the yield of gamma-valerolactone in the first reaction is 95%, and the yield of gamma-valerolactone can still reach 95% after 4 cycles. Reaction conditions and raw material consumption are with embodiment 2. The specific data can be seen in Table 2 below.

Table 2

It can be seen from the above that the catalyst in the present application can be reused, the catalytic efficiency does not change significantly after repeated use, the separation process of the product and the catalyst is simple, and the production cost can be effectively reduced.

Example 24

Take a pressure-resistant Shrek tube, add 1.95mmol furfural, 5%mmol Sc(OTf) ₃ , add 1.5mL isopropanol, stir, react at 100°C for 2 hours, take a sample for NMR detection, and its in-situ NMR image can be seen in Fig. 5.

It can be seen from Figure 5 that under the above reaction conditions, in the process of producing γ-valerolactone with furfural as a substrate, it has experienced the intermediate process of furfuryl alcohol, wherein -OH in furfuryl alcohol is an active hydrogen, which cannot be identified according to Figure 5 .

Example 25

On the basis of Example 24, after raising the temperature to 150°C, the reaction was continued for 3 hours, and a sample was taken for NMR detection. The in-situ NMR map can be seen in FIG. 6 .

It can be known from Fig. 6 that under the above reaction conditions, in the process of generating γ-valerolactone with furfural as the substrate, the intermediate process of isopropyl levulinate was experienced. In Figure 6, the methyl groups 5 and 6 overlap with the solvent peak and cannot be assigned.

Example 26

Take a pressure-resistant Shrek tube, add 0.05mmol furfural, 5%mmol Sc(OTf) ₃ , add 3mL isopropanol, stir, and react at 150°C for 36h. After removing isopropanol, take a sample for NMR detection. The picture can be seen in Figure 7.

It can be seen from Figure 7 that under the above reaction conditions, furfural is used as the substrate, and the final product is γ-valerolactone.

Example 27

Take a pressure-resistant Shrek tube, add 0.24mmol furfuryl alcohol, 5%mmol Sc(OTf) ₃ , add 0.3mL absolute ethanol and 0.2mL C ₆ D ₆ , stir, react at 100°C for 30min, and take a sample for NMR detection. Its NMR image can be seen in Figure 8.

As can be seen from Figure 8, under the above-mentioned reaction conditions, in the process of generating ethyl levulinate as a substrate with furfuryl alcohol, the process of furfuryl ethyl ether and 4,5,5-triethoxy-2-pentanone process.

The preparation of embodiment 28 levulinic acid ester compounds

Take a pressure-resistant Shrek tube, add furfuryl ethyl ether and water (molar ratio 1:1), add Sc(OTf) ₃ , add 3 mL of ethanol, stir, react at 100°C for 12 hours, and measure the conversion rate of raw materials and product yield , see Table 3 for details.

The preparation method of embodiment 29～31 is the same as embodiment 28. Its raw materials, catalyst type and reaction conditions can be seen in Table 3, and the levulinic acid ester productive rate can also be seen in Table 3.

table 3

It can be seen from the above table:

(1) Embodiment 28 and comparative example 7 illustrate, with Sc (OTf) ₃ in the reaction that catalyzed furfuryl ethyl ether generates ethyl levulinate, when not containing water in the raw material, the yield of ethyl levulinate Significant decrease (from 68% to 22%);

(2) Examples 29 to 31 illustrate that in _the reaction of catalyzed furfuryl ethyl ether to generate levulinic acid esters with Sc(OTf), the alcohol source has a significant impact on the yield of levulinic acid esters. Under certain reaction conditions, when the alcohol source is tert-butanol, the yield of levulinic acid ester compounds is the highest, up to 90%.

Comparative example 1

Take a pressure-resistant Shrek tube, add 0.5mmol furfural, 5%mmol Sc ₂ O ₃ , add 3mL isopropanol, stir, and react at 150°C for 36h, the yield of furfuryl alcohol, the yield of isopropyl levulinate and γ - The valerolactone yields were all 0%.

Comparative example 2

Take a pressure-resistant Shrek tube, add 0.5mmol furfural, 5%mmol Al(iPrO) ₃ , add 3mL isopropanol, stir, and react at 150°C for 36h. The yield of furfuryl alcohol is 93%. Isopropyl levulinate The yield was 0%, the yield of γ-valerolactone was 0%.

Comparative example 3

Take a pressure-resistant Shrek tube, add 0.5mmol furfural, 5%mmol Phy-Zr, add 3mL isopropanol, stir, and react at 150°C for 36h, the yield of furfuryl alcohol is 99%, and the yield of isopropyl levulinate was 0%, and the yield of γ-valerolactone was 0%.

Comparative example 4

Take a pressure-resistant Shrek tube, add 0.5mmol furfural, 5%mmol ScCl ₃ 6H ₂ O, add 3mL isopropanol, stir, and react at 150°C for 36h, the yield of isopropyl levulinate is 35%, The yield of γ-valerolactone was 0%.

Comparative example 5

Take a pressure-resistant Shrek tube, add 0.5mmol furfural, 5%mmol ScCl ₃ , add 3mL isopropanol, stir, and react at 150°C for 36h, the yield of isopropyl levulinate is 33%, and γ-valerolactone The yield was 0%.

Comparative example 6

Take a pressure-resistant Shrek tube, add 0.5mmol furfural, 5%mmol Al(OTf) ₃ , add 3mL isopropanol, stir, and react at 150°C for 36h. The yield of furfuryl alcohol is 35%. Isopropyl levulinate The yield was 32%, the yield of γ-valerolactone was 0%.

Comparative example 7

Take a pressure-resistant Shrek tube, add 0.5mmol furfuryl ethyl ether, 5%mmol Sc(OTf) ₃ , add 3mL ethanol, stir, react at 100°C for 12h, and the yield of ethyl levulinate is 22%.

Claims (20)

1. A preparation method for gamma-valerolactone is characterized in that it comprises the steps of, under catalyst action, furfural and secondary alcohol are reacted to obtain gamma-valerolactone; The catalyst is M(R)n, wherein M is selected from Ce, Sc, Y, Yb or Lu; R is selected from trifluoromethanesulfonate or perfluorobutanesulfonate; n is 3; The secondary alcohol is a secondary alcohol selected from C ₃ -C ₆ ;

2. the preparation method of gamma-valerolactone as claimed in claim 1, is characterized in that, described M is Sc. 3. the preparation method of gamma-valerolactone as claimed in claim 1 is characterized in that, described catalyst is Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , One or more of Yb(OTf) ₃ and Lu(OTf) ₃ ; And/or, the molar ratio of the catalyst to the furfural is (0.1-100):100; And/or, the secondary alcohol is isopropanol; And/or, the reaction is carried out in an inert solvent; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the furfural are 3:(0.01～1); And/or, the temperature of the reaction is 100-200°C; And/or, the reaction time is 6-48 hours. 4. the preparation method of gamma-valerolactone as claimed in claim 3 is characterized in that, described catalyst is Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ or Lu(OTf) ₃ ; And/or, the molar ratio of described catalyst and described furfural is (1～10):100; And/or, the inert solvent is one or more of hexane, benzene, carbon tetrachloride and ethylene dichloride; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the furfural are 3:(0.05～0.5); And/or, the temperature of the reaction is 140-170°C; And/or, the reaction time is 24-48 hours. 5. the preparation method of gamma-valerolactone as claimed in claim 4, is characterized in that, the mol ratio of described catalyzer and described furfural is 5:100; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the furfural are 3:0.05, 3:0.1, 3:0.125, 3:0.25 or 3:0.5; And/or, the temperature of the reaction is 140°C, 150°C or 170°C; And/or, the reaction time is 24h, 36h or 48h. 6. A preparation method for gamma-valerolactone, characterized in that it comprises the steps of reacting furfuryl alcohol and secondary alcohol under the action of a catalyst to prepare gamma-valerolactone; The catalyst is M(R)n, wherein M is selected from Ce, Sc, Y, Yb or Lu; R is selected from trifluoromethanesulfonate or perfluorobutanesulfonate; n is 3; The secondary alcohol is a secondary alcohol selected from C ₃ -C ₆ ;

7. the preparation method of gamma-valerolactone as claimed in claim 6, is characterized in that, described M is Sc. 8. the preparation method of gamma-valerolactone as claimed in claim 6 is characterized in that, the mol ratio of described catalyst and described furfuryl alcohol is (0.1～100): 100; And/or, the catalyst is one or more of Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ and Lu(OTf) ₃ ; And/or, the secondary alcohol is isopropanol; And/or, the reaction is carried out in an inert solvent; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the furfuryl alcohol is 3: (0.01～1); And/or, the temperature of the reaction is 100-200°C; And/or, the reaction time is 6-48 hours. 9. the preparation method of gamma-valerolactone as claimed in claim 8 is characterized in that, the mol ratio of described catalyzer and described furfuryl alcohol is (1～10): 100; And/or, the catalyst is Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ or Lu(OTf) ₃ ; And/or, the inert solvent is one or more of hexane, benzene, carbon tetrachloride and ethylene dichloride; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the furfuryl alcohol are 3:(0.05～0.5); And/or, the temperature of the reaction is 140-170°C; And/or, the reaction time is 24-48 hours. 10. the preparation method of gamma-valerolactone as claimed in claim 8, is characterized in that, the mol ratio of described catalyzer and described furfuryl alcohol is 5:100; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the furfuryl alcohol are 3:0.125; And/or, the temperature of the reaction is 150°C; And/or, the reaction time is 36h. 11. A preparation method for gamma-valerolactone, characterized in that it comprises the steps of, under the action of a catalyst, reacting levulinic acid ester compounds shown in formula I and secondary alcohols to prepare gamma - valerolactone, that is enough; R ₁ is H or C ₁ ~ C ₄ alkyl; The catalyst is M(R)n, wherein M is selected from Ce, Sc, Y, Yb or Lu; R is selected from trifluoromethanesulfonate or perfluorobutanesulfonate; n is 3; The secondary alcohol is a secondary alcohol selected from C ₃ -C ₆ ;

12. The preparation method of γ-valerolactone as claimed in claim 11, characterized in that, said M is Sc. 13. the preparation method of gamma-valerolactone as claimed in claim 11, is characterized in that, the mol ratio of described catalyzer and described levulinic acid ester compound shown in formula I is (0.1～100): 100; And/or, the catalyst is one or more of Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ and Lu(OTf) ₃ ; And/or, the secondary alcohol is isopropanol; And/or, the reaction is carried out in an inert solvent; And/or, the C ₁ -C ₄ alkyl group is selected from methyl, ethyl, isopropyl or tert-butyl; And/or, the molar ratio of the volume mL of the secondary alcohol to the levulinic acid ester compound shown in formula I is 3: (0.01-1); And/or, the temperature of the reaction is 100-200°C; And/or, the reaction time is 6-48 hours. 14. the preparation method of gamma-valerolactone as claimed in claim 13, is characterized in that, the mol ratio of described catalyzer and described levulinate compound shown in formula I is (1～10): 100; And/or, the catalyst is Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ or Lu(OTf) ₃ ; And/or, the inert solvent is one or more of hexane, benzene, carbon tetrachloride and ethylene dichloride; And/or, the molar ratio of the volume mL of the secondary alcohol to the levulinic acid ester compound shown in formula I is 3: (0.05-0.5); And/or, the temperature of the reaction is 140-170°C; And/or, the reaction time is 24-48 hours. 15. the preparation method of γ-valerolactone as claimed in claim 14, is characterized in that, the mol ratio of described catalyzer and described levulinic acid ester compound shown in formula I is 5:100 or 10: 100; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the levulinic acid ester compound shown in formula I are 3:0.5; And/or, the temperature of the reaction is 150°C; And/or, the reaction time is 24h. 16. A preparation method for gamma-valerolactone, characterized in that it comprises the following steps, under the action of a catalyst, reacting xylose-type biomass and secondary alcohol to prepare gamma-valerolactone, that is, ; The catalyst is M ¹ (R ¹ )n ¹ , wherein M ¹ is selected from Ce, Sc, Y, Yb or Lu; R ¹ is selected from trifluoromethanesulfonic acid group or perfluorobutanesulfonic acid group; n ¹ is 3 ; The xylose-type biomass is one or more of corncobs, xylan and xylose; The secondary alcohol is a secondary alcohol selected from C ₃ -C ₆ ;

17. the preparation method of gamma-valerolactone as claimed in claim 16, is characterized in that, described M ¹ is Sc. 18. the preparation method of gamma-valerolactone as claimed in claim 16 is characterized in that, before reacting, described xylose-type biomass needs to be ground and dried; And/or, the catalyst is one or more of Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ and Lu(OTf) ₃ ; And/or, the secondary alcohol is isopropanol; And/or, the reaction is carried out in an inert solvent; And/or, the molar ratio of the catalyst to the biomass is (0.1-100):100; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the biomass is 3:(0.001～0.1); or, the volume mL of the secondary alcohol and the mass mg ratio of the biomass is 3: (10～100); And/or, the temperature of the reaction is 150-250°C; And/or, the reaction time is 6-48 hours. 19. The preparation method of γ-valerolactone as claimed in claim 18, characterized in that, the catalyst is Ce(OTf) ₃ , Sc(ONf) ₃ , Sc(OTf) ₃ , Y(OTf) ₃ , Yb(OTf) ₃ or Lu(OTf) ₃ ; And/or, the inert solvent is one or more of hexane, benzene, carbon tetrachloride and ethylene dichloride; And/or, the molar ratio of the catalyst to the biomass is (10-30):100; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the biomass is 3:(0.025～0.05); or, the volume mL of the secondary alcohol and the mass mg ratio of the biomass is 3: (20～50); And/or, the temperature of the reaction is 170-210°C; And/or, the reaction time is 24-48 hours. 20. the preparation method of γ-valerolactone as claimed in claim 19, is characterized in that, the mol ratio of described catalyst and described biomass is 20:100; And/or, the volume mL of the secondary alcohol and the molar mmol ratio of the biomass are 3:0.025 or 3:0.05; or, the volume mL of the secondary alcohol and the mass mg ratio of the biomass are 3: 25; And/or, the temperature of the reaction is 190°C; And/or, the reaction time is 24 or 48 hours.

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