WO2021218669A1

WO2021218669A1 - Method for realizing high-efficiency circulation of vanadium and sulfuric acid with trace dmso to catalyze biomass in order to prepare formic acid

Info

Publication number: WO2021218669A1
Application number: PCT/CN2021/087857
Authority: WO
Inventors: 李洋; 郭晏君; 孙远利; 张秀锋
Original assignee: 西安交通大学
Priority date: 2020-04-29
Filing date: 2021-04-16
Publication date: 2021-11-04
Also published as: CN111454139B; CN111454139A

Abstract

A method for realizing high-efficiency circulation of vanadium and sulfuric acid with trace DMSO to catalyze biomass in order to prepare formic acid. The method comprises firstly placing biomass or domestic waste into dilute sulphuric acid, and then adding sodium metavanadate and DMSO for oxidation and hydrolysis, such that cellulose and hemicellulose are quantificationally converted into formic acid, so as to obtain oxidation and hydrolysis solution A; then separating the oxidation and hydrolysis solution A by means of reduced pressure distillation to obtain a fraction B and a mother liquor C, wherein the fraction B is an aqueous solution of the formic acid, which is subjected to subsequent separation or application; then adding DMSO and water into the mother liquor C, and heating and stirring same to combine them to obtain active mother liquor D; and then placing a biomass or domestic waste into the active mother liquor D for oxidation and hydrolysis, such that cellulose and hemicellulose are quantitatively converted into a formic acid solution, so as to obtain an oxidation and hydrolysis solution; and finally, adding the oxidation and hydrolysis solution into the oxidation and hydrolysis solution A, and repeating the above steps to realize cycling of the system. The present invention has a good compatibility, a high yield of formic acid preparation, a simple post-treatment, and no decrease in the formic acid yield after multiple cycles, which reduces the cost and environmental pollution thereof.

Description

Method for realizing high-efficiency circulation of vanadium and sulfuric acid to catalyze biomass to prepare formic acid with trace DMSO

Technical field

The invention belongs to the technical field of formic acid preparation, and in particular relates to a method for preparing formic acid from biomass by catalyzing the high-efficiency circulation of vanadium and sulfuric acid with trace DMSO.

Background technique

Formic acid is one of the basic chemical raw materials and has a wide range of applications in various fields such as medicine, papermaking, agriculture, textile printing and dyeing. In recent years, as a potential hydrogen storage material, formic acid has attracted wide attention from scientists. At present, the main industrial methods for preparing formic acid are the formamide method and the methyl formate method. The raw materials used in these traditional methods (high-pressure carbon monoxide and methanol) are all from non-renewable fossil resources, and the toxicity of carbon monoxide is relatively high, prompting researchers to develop a green and sustainable formic acid production method. Biomass is renewable, low-cost, low-pollution, and widely distributed, and can be developed as a raw material for the production of chemicals. At present, the use of biomass as a raw material to prepare formic acid is still in the research stage. If formic acid can be prepared from biomass with high efficiency, high yield and low energy consumption under mild conditions, it will promote the innovation of formic acid industrial production.

At present, there are two main methods for preparing formic acid from biomass. The first is the alkali-hydroxide method, and the second is the hydrothermal oxidation method using vanadium as a catalyst. The alkali-hydroxide method uses H ₂ O ₂ (hydrogen peroxide) as the oxidant, water as the solvent, and sodium hydroxide and other bases as stable formic acid reagents and catalysts to prepare formic acid (Fangming Jin, Enomoto H. Rapid and highly selective conversion). of biomass into value-added products in hydrothermal conditions:Chemistry of acid/base-catalysed and oxidation reactions.Energy Environ.Sci.2011,4,382–397.Jun Yun,Guodong Yao,Fangming Jin,et al.Low-Temperature and Highly Efficient Conversion of Saccharides into Formic Acid under Hydrothermal Conditions.AIChE J.2016,62,3657-3663.Can Wang,Xi Chen,Man Qi,et al.Room temperature,near-quantitative conversion of glucose into formic acid.Green Chem.2019 , 21, 6089-6096.). The oxidant required by the alkali-hydroxide method is H ₂ O ₂ , which has strong oxidizing properties, and the formic acid generated in the reaction will be further oxidized. Therefore, a large amount of alkali is added in the reaction to improve the selectivity and yield of formic acid , The reaction produces formate instead of formic acid, which limits the direct application of formic acid in the subsequent reaction; this method has a limited degree of conversion of cellulose in the original ecological biomass, and a large amount of alkali and oxidant need to be added in each cycle H ₂ O _{2 is} not conducive to industrial recycling applications.

The vanadium-containing hydrothermal oxidation method uses vanadium-containing compounds as a catalyst, water as a solvent, and oxygen as an oxidant to produce formic acid at temperatures below 200°C. The vanadium-containing compounds mainly include heteropolyacids (HPA-x, x=0 -6), VOSO ₄ , NaVO ₃ three types.

Heteropoly acids are oxygen-containing acids formed by multiple atoms (such as V, Mo, P, etc.) connected by oxygen bridges according to certain rules. Heteropolyacids have a good catalytic effect on small-molecule sugar monomers, but the conversion and decomposition of cellulose in the original ecological biomass is very limited. Therefore, the auxiliary agent p-toluene sulfonic acid (TSA) and organic solvents such as n-hexanol and n-heptanol are added to these systems to further increase the reaction yield (Albert J,

R,Bosmann A,et al.Selective oxidation of complex,water-insoluble biomass to formic acid using additives as reaction accelerators.Energy Environ.Sci.2012,5,7956–7962.

R,Taccardi N,

A,et al.Selective catalytic conversion of biobased carbohydrates to formic acid using molecular oxygen.Green Chem.2011,13,2759-2763.Albert J,Lüders D,

A,et al.Spectroscopic and electrochemical characterization of heteropoly acids for their optimized application in selective biomass oxidation to formic acid.Green Chem.2014,16,226–237.Jenny Reichert,Birgit Brunner,Andreas Jess,et al.,Biomass oxidation to formic acid in aqueous media using polyoxometalate catalysts–boosting FA selectivity by in-situ extraction.Energy Environ.Sci.2015,8,2985-2990.). The selectivity of the production of formic acid from biomass catalyzed by heteropoly acid is not high, and a large amount of organic acid additives and organic solvents are added, which also increases the cost of the reaction invisibly and is not conducive to the purification of formic acid.

The VOSO ₄ catalytic system is _{to add ethanol and other alcohol compounds to the VOSO 4} system to reduce the excessive oxidation of formic acid and increase the yield of formic acid (Tang Z, Deng W, Wang Y, et al., Transformation of cellulose and its derived carbohydrates into formic and lactic acids catalyzed by vanadyl cations.ChemSusChem 2014,7,1557–1567.). The concentration of the reaction raw materials in this method is very low, the water required for the same raw material amount and the addition of a large amount of alcohols increase the cost of the reaction, and it is also not conducive to the separation and large-scale circulation of formic acid.

The NaVO ₃ /H ₂ SO ₄ catalytic system is to _{add NaVO 3 to} an aqueous solution _{containing dilute H 2} SO ₄ to produce formic acid, and realize the conversion of cellulose in the original ecological biomass, such as wheat straw and other biomass (Wang WH ,Niu MG,Hou YC,et al.,Catalytic conversion of biomass-derived carbohydrates to formic acid using molecular oxygen.Green Chem.2014,16,2614–2618.Niu MG,Hou YC,Ren SH,et al.,Conversion of wheat straw into formic acid in NaVO ₃ -H ₂ SO ₄ aqueous solution with molecular oxygen. Green Chem. 2015, 17, 453–459.). The method uses ether extraction to realize the separation of formic acid, and the yield of formic acid is only 47%, which needs to be further improved, which is not conducive to the wide application in industry.

Although the method of "preparing formic acid from non-food biomass" has made certain progress in the alkali-peroxidation method with hydrogen peroxide as the oxidant or the hydrothermal oxidation method with vanadium as the oxidant as the catalyst, it is still in practical applications. There are big limitations. In the existing methods, the goals of high-yield conversion of glucose, conversion of original ecological biomass, and recyclability have been achieved respectively. However, how to simultaneously realize the high-yield preparation of formic acid from original ecological biomass and the high-efficiency circulation of the catalytic system is a very important issue. Challenging subject. The realization of this subject will show its potential industrial application prospects.

To sum up, the existing technologies for preparing formic acid from biomass all have problems that cannot simultaneously satisfy the conversion of glucose with a higher yield, the conversion of raw biomass with a high yield, and the low cost of a catalytic cycle.

Summary of the invention

In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a method for catalyzing the production of formic acid from biomass by using a trace of DMSO to efficiently circulate vanadium and sulfuric acid. And domestic waste to prepare formic acid.

In order to achieve the above objective, the technical solution adopted by the present invention is:

A method for achieving efficient circulation of vanadium and sulfuric acid to catalyze the production of formic acid from biomass with trace DMSO, including the following steps:

1) Put the biomass or domestic waste in dilute sulfuric acid with a mass concentration of 0.5-1.5%, then add sodium metavanadate and DMSO, and perform oxidative hydrolysis at 2.0-7.0MPa and 140-170℃ to make cellulose and Hemicellulose is quantitatively converted into formic acid to obtain oxidized hydrolysate A;

Among them, add 15-45mL of dilute sulfuric acid, 0.05-0.15g of sodium metavanadate, and 0-2mL of DMSO for every 1g of biomass or domestic waste;

2) Separate the oxidized hydrolysate A by distillation under reduced pressure at 45-65°C to obtain fraction B and mother liquor C. Fraction B is an aqueous solution of formic acid. The aqueous solution of formic acid is subjected to subsequent separation or application. Mother liquor C is concentrated sulfuric acid and sodium metavanadate.的catalysis system;

3) Add a small amount of DMSO and water required for the reaction to mother liquor C, and then heat to 50-95°C and stir for five minutes to one hour to fully combine to obtain active mother liquor D; among them, add 0.1 for every 1g of biomass or domestic garbage -0.5mL of DMSO;

4) Put the biomass or domestic waste of the same quality as in step 1) in the active mother liquor D, and conduct oxidative hydrolysis at 2.0-7.0MPa and 140-170°C to quantitatively convert cellulose and hemicellulose into formic acid solution , Get oxidized hydrolysate.

The oxidized hydrolysis liquid obtained in step 4) is added to the oxidized hydrolysis liquid A of step 2), and steps 2), 3), and 4) are circulated to realize the circulation of the system.

The biomass used is wheat stalk, corn stalk, rice stalk or reed stalk.

The household garbage is bagasse, cardboard paper or waste newspaper.

The oxidative hydrolysis of step 1) and step 4) is carried out in oxygen or air.

The added water in step 3) is distilled circulating water.

The beneficial effects of the present invention are:

The invention adopts trace DMSO to realize the method for preparing formic acid by catalyzing the biomass through the efficient circulation of vanadium and sulfuric acid, which has good compatibility. Compared with the prior art, the production rate of formic acid from the original ecological biomass is high, the post-treatment is simple, the production rate of formic acid is not reduced in multiple cycles, and the cycle yield of formic acid production from wheat straw is ≥95%; the present invention is an aqueous phase The reaction system does not require a large amount of organic solvents to participate, which reduces the cost and environmental pollution. Compared with other catalytic systems, the catalytic system of the present invention has strong compatibility (compatible with various biomass and domestic garbage), high selectivity (≥95%), and low cycle cost (simple vacuum distillation and addition of trace DMSO).

Description of the drawings

Figure 1 is a schematic flow diagram of the present invention.

Detailed ways

The present invention will be described in detail below with reference to the drawings and embodiments.

Embodiment 1, referring to Fig. 1, a method for producing formic acid from biomass through highly efficient circulation of vanadium and sulfuric acid in a trace of DMSO, including the following steps:

1) In a glass reactor, add 0.94 g of wheat straw with a 200 mesh sieve, 30 mL of dilute sulfuric acid with a mass concentration of 0.7%, 0.08 g of sodium metavanadate and 0.31 mL of DMSO. At room temperature, magnetically stir until partial Sodium vanadate is fully dissolved, placed in an autoclave, heated to 160°C, and oxidized and hydrolyzed in 3.0MPa air to obtain oxidized hydrolysate A of wheat straw, and 1,4-dioxane is added as an internal standard. The ^{content of formic acid in the oxidized hydrolysis solution A was determined by 1} H NMR to be 18 mmol, and the yield of formic acid was 100% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

2) Separate the oxidized hydrolysate A by 55°C under reduced pressure distillation to obtain fraction B and mother liquor C. Fraction B is mainly an aqueous solution of formic acid. This solution can be separated or applied later. Mother liquor C contains sulfuric acid and sodium metavanadate. ；

3) Add a small amount of 0.31 mL of DMSO and the water required for the reaction to mother liquor C, then heat to 90°C and stir for ten minutes to fully react to obtain active mother liquor D;

4) Put 0.94 g of wheat straw with a 200 mesh sieve in active mother liquor D, place it in an autoclave, heat to 160°C, and perform oxidative hydrolysis in 3.0MPa air to obtain an oxidized hydrolysate of wheat straw, and add 1 to it. , 4-Dioxane was used as the internal standard, and the ^{content of formic acid in the hydrolysate was determined to be 18 mmol by 1} H NMR, and the yield of formic acid was 100% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

5) Add the oxidized hydrolysate obtained in step 4) to the oxidized hydrolyzed solution A of step 2), and circulate steps 2), 3), and 4) for a total of 3 times. The yields of formic acid are 100%, 99%, and 100%.

Embodiment 2, referring to Fig. 1, a method for achieving efficient circulation of vanadium and sulfuric acid to catalyze the production of formic acid from biomass with trace DMSO, including the following steps:

1) In a glass reactor, add 2.82 g of wheat straw with a 200 mesh sieve, 90 mL of dilute sulfuric acid with a mass concentration of 0.7%, 0.24 g of sodium metavanadate and 0.93 mL of DMSO. Sodium vanadate is fully dissolved, placed in an autoclave, heated to 160°C, and oxidized and hydrolyzed in oxygen at 3.0 MPa to obtain an oxidized hydrolysate A of wheat straw. Add 1,4-dioxane to the oxidized hydrolysate A The ring is used as an internal standard, and the ^{content of formic acid in the hydrolysate is determined by 1} H NMR to be 53 mmol, and the yield of formic acid is 99% (calculated based on the C atoms of cellulose and hemicellulose in the feeding amount);

2) Separate the oxidized hydrolysate A by 55°C vacuum distillation to obtain fraction B and mother liquor C. Fraction B is mainly an aqueous solution of formic acid. This solution can be separated or applied later. Mother liquor C contains sulfuric acid and sodium metavanadate. ；

3) Add 0.93 mL of DMSO and the water required for the reaction to mother liquor C, and then heat to 90°C and stir for ten minutes to fully react to obtain active mother liquor D;

4) Put 2.82g of wheat straw with 200 mesh sieve in the middle active mother liquor D, place it in an autoclave, heat it to 160°C, and perform oxidative hydrolysis in 3.0MPa oxygen to obtain an oxidized hydrolysate of wheat straw. 1,4-dioxane was added as an internal standard, and the ^{content of formic acid in the hydrolysate was determined by 1} H NMR to be 53 mmol, and the yield of formic acid was 99% (calculated based on the C atoms of cellulose and hemicellulose in the feeding amount);

5) Add the oxidized hydrolysate obtained in step 4) to the oxidized hydrolysate A of step 2), and circulate step 2), step 3), and step 4) three times. The yields of formic acid are 100%, 99%, and 100%, respectively. %.

Embodiment 3, referring to Fig. 1, a method for catalyzing the production of formic acid from biomass through the highly efficient circulation of vanadium and sulfuric acid in a trace of DMSO includes the following steps:

1) In a glass reactor, 9.42g of chopped wheat straw, 300mL of dilute sulfuric acid with a mass concentration of 0.7%, 0.81g of sodium metavanadate and 3.1mL of DMSO, magnetically stirred to metavanadic acid at room temperature Sodium is fully dissolved, placed in an autoclave, heated to 160°C, and oxidized and hydrolyzed in oxygen at 5.0 MPa to obtain an oxidized hydrolysate A of wheat straw, and 1,4-dioxane is added to the oxidized hydrolysate A as Internal standard, the ^{content of formic acid in the oxidized hydrolysate A determined by 1} H NMR was 179 mmol, and the yield of formic acid was 99% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

2) Separate the oxidized hydrolysate A by vacuum distillation at 55°C to obtain fraction B and mother liquor C. Fraction B is mainly an aqueous solution of formic acid. This solution can be separated or applied later. Mother liquor C contains sulfuric acid and sodium metavanadate;

3) Add 3.1 mL of DMSO and the water required for the reaction to mother liquor C, and then heat to 90°C and stir for 30 minutes to fully react to obtain active mother liquor D;

4) Put 9.42g of the chopped wheat straw into active mother liquor D, place it in an autoclave, heat to 160°C, and perform oxidative hydrolysis in 5.0MPa oxygen to obtain an oxidized hydrolysate of wheat straw, and add 1,4 to it -Dioxane was used as the internal standard, and the ^{content of formic acid in the hydrolyzate was determined by 1} H NMR to be 179 mmol, and the yield of formic acid was 99% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

5) Add the oxidized hydrolysate obtained in step 4) to the oxidized hydrolyzed solution A of step 2), and circulate step 2), step 3), and step 4) three times. The yields of formic acid are 99%, 99%, and 98, respectively. %.

Embodiment 4, referring to Fig. 1, a method for catalyzing the production of formic acid from biomass through the high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO includes the following steps:

1) In a glass reactor, add 3.03g corn stalks with a 200-mesh sieve, 90mL dilute sulfuric acid with a mass concentration of 0.7%, 0.24g sodium metavanadate and 0.93mL DMSO, and magnetically stir at room temperature until it becomes partial. Sodium vanadate is fully dissolved, placed in an autoclave, heated to 160°C, and oxidized and hydrolyzed in oxygen at 3.0 MPa to obtain oxidized hydrolysate A of corn stover, and 1,4-dioxane is added as an internal standard. , The ^{content of formic acid in the oxidized hydrolysis solution A was determined by 1} H NMR to be 43 mmol, and the yield of formic acid was 79% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

4) Put 3.03g of 200-mesh sieve corn stalks in active mother liquor D, place them in an autoclave, heat to 160°C, and perform oxidative hydrolysis in 3.0MPa oxygen to obtain an oxidized hydrolysate of corn stalks, and add 1, 4-Dioxane was used as an internal standard, and the ^{content of formic acid in the hydrolysate was determined by 1} H NMR to be 52 mmol, and the yield of formic acid was 78% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Embodiment 5, referring to Fig. 1, a method for catalyzing the production of formic acid from biomass through the high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO includes the following steps:

1) In a glass reactor, add 3.10g rice straw with a 200 mesh sieve, 90mL dilute sulfuric acid with a mass concentration of 0.7%, 0.24g sodium metavanadate and 0.93mL DMSO, and magnetically stir at room temperature until it becomes partial. Sodium vanadate is fully dissolved, placed in an autoclave, heated to 160°C, and oxidized and hydrolyzed in oxygen at 3.0MPa to obtain oxidized hydrolysate A of rice straw, and 1,4-dioxane is added as an internal standard. , The ^{content of formic acid in the oxidized hydrolysis solution A was determined by 1} H NMR to be 46 mmol, and the yield of formic acid was 85% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

4) Put 3.10g of rice straw with a 200 mesh sieve into active mother liquor D, place it in an autoclave, heat to 160°C, and perform oxidative hydrolysis in 3.0MPa oxygen to obtain an oxidized hydrolysate of rice straw, and add 1, 4-Dioxane was used as an internal standard, and the ^{content of formic acid in the hydrolysate was determined by 1} H NMR to be 47 mmol, and the yield of formic acid was 87% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Embodiment 6, referring to Fig. 1, a method for catalyzing the production of formic acid from biomass through the high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO, including the following steps:

1) In a glass reactor, add 3.64 g reed straws with a 200 mesh sieve, 90 mL dilute sulfuric acid with a mass concentration of 0.7%, 0.24 g sodium metavanadate and 0.93 mL DMSO. Sodium vanadate is fully dissolved, placed in an autoclave, heated to 160℃, and oxidized and hydrolyzed in oxygen at 3.0MPa to obtain oxidized hydrolysate A of reed straw, and 1,4-dioxane is added as an internal standard. , The ^{content of formic acid in the oxidized hydrolysis solution A was determined by 1} H NMR to be 46 mmol, and the yield of formic acid was 85% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

4) Put 3.64g of 200-mesh reed straw into active mother liquor D, place it in an autoclave, heat to 160°C, and perform oxidative hydrolysis in 3.0MPa oxygen to obtain an oxidized hydrolysate of reed straw, and add 1, 4-Dioxane was used as the internal standard, and the ^{content of formic acid in the hydrolysate was determined by 1} H NMR to be 46 mmol, and the yield of formic acid was 85% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Embodiment 7, referring to Fig. 1, a method for catalyzing the production of formic acid from biomass through the high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO, including the following steps:

1) In a glass reactor, add 2.80 g of bagasse with a 200 mesh sieve, 90 mL of dilute sulfuric acid with a mass concentration of 0.7%, 0.24 g of sodium metavanadate, and 0.93 mL of DMSO. Sodium vanadate is fully dissolved, placed in an autoclave, heated to 160°C, and oxidized and hydrolyzed in oxygen at 3.0 MPa to obtain oxidized hydrolysate A of bagasse, and 1,4-dioxane is added as an internal standard , The ^{content of formic acid in the oxidized hydrolysis solution A was determined by 1} H NMR to be 57 mmol, and the yield of formic acid was 106% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

3) Add a trace amount of 0.93 mL of DMSO and the water required for the reaction to mother liquor C, then heat to 90°C and stir for ten minutes to fully react to obtain active mother liquor D;

4) Put 2.80 g of bagasse with a 200 mesh sieve into active mother liquor D, place it in an autoclave, heat to 160°C, and perform oxidative hydrolysis in 3.0MPa oxygen to obtain an oxidized hydrolysate of bagasse. Add 1, 4-dioxane was used as an internal standard, and the ^{content of formic acid in the hydrolyzate was determined by 1} H NMR to be 55 mmol, and the yield of formic acid was 101% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Embodiment 8, referring to Fig. 1, a method for catalyzing the production of formic acid from biomass through the high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO, including the following steps:

1) In a glass reactor, 2.60g of powdered cardboard paper, 90mL of dilute sulfuric acid with a mass concentration of 0.7%, 0.24g of sodium metavanadate and 0.93mL of DMSO, magnetically stirred to vanadium at room temperature Sodium is fully dissolved, placed in an autoclave, heated to 160°C, and oxidized and hydrolyzed in oxygen at 3.0 MPa to obtain oxidized hydrolysate A of cardboard paper, and 1,4-dioxane is added as an internal standard. , The ^{content of formic acid in the oxidized hydrolysis solution A was determined by 1} H NMR to be 59 mmol, and the yield of formic acid was 90% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

4) Put 2.60g of the powdered cardboard paper in the active mother liquor D, place it in the autoclave, heat to 160℃, and perform oxidative hydrolysis in 3.0MPa oxygen to obtain the oxidized hydrolysate of the cardboard paper, and add it to it 1,4-Dioxane was used as an internal standard, and the ^{content of formic acid in the hydrolysate was determined by 1} H NMR to be 50 mmol, and the yield of formic acid was 92% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Example 9, referring to Fig. 1, a method for producing formic acid from biomass through the high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO, including the following steps:

1) In a glass reactor, 2.89g of crushed waste newspaper, 90mL of dilute sulfuric acid with a mass concentration of 0.7%, 0.24g of sodium metavanadate and 0.93mL of DMSO, magnetically stirred to sodium metavanadate at room temperature Fully dissolve it, place it in an autoclave, heat to 160℃, perform oxidative hydrolysis in oxygen at 3.0MPa to obtain oxidized hydrolysate A of waste newspaper, add 1,4-dioxane as an internal standard, and use ¹ The content of formic acid in the oxidized hydrolysis solution A determined by H NMR was 46 mmol, and the yield of formic acid was 86% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

4) Put 2.89g of crushed waste newspaper in active mother liquor D, place it in an autoclave, heat to 160°C, perform oxidative hydrolysis in 3.0MPa oxygen to obtain an oxidized hydrolysate of waste newspaper, and add 1,4 to it -Dioxane was used as an internal standard, and the ^{content of formic acid in the hydrolyzate was determined by 1} H NMR to be 46 mmol, and the yield of formic acid was 86% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Embodiment 10, referring to Fig. 1, a method for producing formic acid from biomass through the high-efficiency cycle of vanadium and sulfuric acid with trace DMSO, including the following steps:

1) In a glass reactor, add 1.03 g corn stalks with a 200-mesh sieve, 15 mL dilute sulfuric acid with a mass concentration of 0.5%, 0.07 g sodium metavanadate and 1.00 mL DMSO, and magnetically stir at room temperature until partial Sodium vanadate is fully dissolved, placed in an autoclave, heated to 140°C, and oxidized and hydrolyzed in air at 3.0MPa to obtain oxidized hydrolysate A of corn stover, and 1,4-dioxane is added as an internal standard. , Using ¹ H NMR to determine the content of formic acid in the oxidized hydrolysis solution A is 10 mmol, and the yield of formic acid is 56% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

2) Separate the oxidized hydrolysate A by 45°C under reduced pressure distillation to obtain fraction B and mother liquor C. Fraction B is mainly an aqueous solution of formic acid. This solution can be separated or applied later. Mother liquor C contains sulfuric acid and sodium metavanadate. ；

3) Add 1.00 mL of DMSO and the water required for the reaction to mother liquor C, then heat to 50°C and stir for 60 minutes to fully react to obtain active mother liquor D;

4) Put 1.03g of 200-mesh corn stalks in active mother liquor D, place in an autoclave, heat to 140°C, and perform oxidative hydrolysis in 3.0MPa oxygen to obtain an oxidized hydrolysate of corn stalks, and add 1 to it. ,4-Dioxane was used as an internal standard, and the ^{content of formic acid in the hydrolyzate was determined by 1} H NMR to be 10 mmol, and the yield of formic acid was 56% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Embodiment 11, referring to Fig. 1, a method for catalyzing the production of formic acid from biomass through the high-efficiency cycle of vanadium and sulfuric acid with trace DMSO includes the following steps:

1) In a glass reactor, add 1.20 g of 200-mesh reed straw, 20 mL of 0.8% dilute sulfuric acid, 0.05 g of sodium metavanadate and 0.50 mL of DMSO. At room temperature, magnetically stir until partial Sodium vanadate is fully dissolved, placed in an autoclave, heated to 150°C, and oxidized and hydrolyzed in the air at 5.0 MPa to obtain an oxidized hydrolysate A of reed straw, and 1,4-dioxane is added as an internal standard. , The ^{content of formic acid in the oxidized hydrolysis solution A was determined by 1} H NMR to be 12 mmol, and the yield of formic acid was 60% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

2) Separate the oxidized hydrolysate A at 50°C under reduced pressure to obtain fraction B and mother liquor C. Fraction B is mainly an aqueous solution of formic acid. This solution can be separated or applied later. Mother liquor C contains sulfuric acid and sodium metavanadate. ；

3) Add 1.00 mL of DMSO and the water required for the reaction to mother liquor C, then heat to 70°C and stir for 30 minutes to fully react to obtain active mother liquor D;

4) Put 1.20g of 200-mesh reed straw in active mother liquor D, place it in an autoclave, heat to 150°C, and perform oxidative hydrolysis in 5.0MPa air to obtain an oxidized hydrolysate of reed straw, and add 1 to it. ,4-Dioxane was used as the internal standard, and the ^{content of formic acid in the hydrolysate was determined by 1} H NMR to be 12 mmol, and the yield of formic acid was 60% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Embodiment 12, referring to Fig. 1, a method for catalyzing the production of formic acid from biomass through the high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO includes the following steps:

1) In a glass reactor, add 0.92 g of bagasse with a 200 mesh sieve, 40 mL of dilute sulfuric acid with a mass concentration of 1.2%, 0.12 g of sodium metavanadate, and 0.31 mL of DMSO. Sodium vanadate is fully dissolved, placed in an autoclave, heated to 160°C, oxidized and hydrolyzed in air at 7.0MPa to obtain oxidized hydrolysate A of bagasse, and 1,4-dioxane is added as an internal standard , The ^{content of formic acid in the oxidized hydrolysis solution A was determined by 1} H NMR to be 15 mmol, and the yield of formic acid was 83% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

2) Separate the oxidized hydrolysate A at 60°C under reduced pressure to obtain fraction B and mother liquor C. Fraction B is mainly an aqueous solution of formic acid. This solution can be separated or applied later. Mother liquor C contains sulfuric acid and sodium metavanadate. ；

3) Add 1.5 mL of DMSO and the water required for the reaction to mother liquor C, then heat to 80°C and stir for 20 minutes to fully react to obtain active mother liquor D;

4) Put 0.92 g of bagasse with a 200 mesh sieve in active mother liquor D, place it in an autoclave, heat to 160°C, and perform oxidative hydrolysis in 7.0MPa air to obtain an oxidized hydrolysate of wheat straw, and add 1 to it ,4-Dioxane was used as an internal standard, and the ^{content of formic acid in the hydrolysate was determined by 1} H NMR to be 14 mmol, and the yield of formic acid was 80% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Embodiment 13, referring to Fig. 1, a method for catalyzing the production of formic acid from biomass through the high-efficiency cycle of vanadium and sulfuric acid with trace DMSO, including the following steps:

1) In a glass reactor, 0.85g of crushed cardboard paper, 45mL of dilute sulfuric acid with a mass concentration of 1.2%, 0.15g of sodium metavanadate and 2.00mL of DMSO, at room temperature, magnetically stir to metavanadic acid Sodium is fully dissolved, placed in an autoclave, heated to 180°C, and oxidized and hydrolyzed in oxygen at 3.0 MPa to obtain oxidized hydrolysate A of cardboard paper, and 1,4-dioxane is added as an internal standard. The ^{content of formic acid in the oxidized hydrolysis solution A was determined by 1} H NMR to be 12 mmol, and the yield of formic acid was 67% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount);

2) Separate the oxidized hydrolysate A at 90°C under reduced pressure to obtain fraction B and mother liquor C. Fraction B is mainly an aqueous solution of formic acid. This solution can be separated or applied later. Mother liquor C contains sulfuric acid and sodium metavanadate. ；

3) Add 0.5 mL of DMSO and the water required for the reaction to mother liquor C, then heat to 95°C and stir for five minutes to fully react to obtain active mother liquor D;

4) Put 0.85g of crushed cardboard paper in active mother liquor D, place it in an autoclave, heat to 180°C, and perform oxidative hydrolysis in 3.0MPa oxygen to obtain an oxidized hydrolysate of cardboard paper, and add 1 to it. ,4-Dioxane was used as an internal standard, and the ^{content of formic acid in the hydrolysate was determined by 1} H NMR to be 11 mmol, and the yield of formic acid was 63% (calculated based on the C atoms of cellulose and hemicellulose in the feed amount).

Claims

A method for achieving efficient circulation of vanadium and sulfuric acid to catalyze the production of formic acid from biomass with trace DMSO, which is characterized in that it comprises the following steps:

1) Put the biomass or domestic waste in dilute sulfuric acid with a mass concentration of 0.5-1.5%, then add sodium metavanadate and DMSO, and perform oxidative hydrolysis at 2.0-7.0MPa and 140-170℃ to make cellulose and Hemicellulose is quantitatively converted into formic acid to obtain oxidized hydrolysate A;

Among them, add 15-45mL of dilute sulfuric acid, 0.05-0.15g of sodium metavanadate, and 0-2mL of DMSO for every 1g of biomass or domestic waste;

2) Separate the oxidized hydrolysate A by distillation under reduced pressure at 45-65°C to obtain fraction B and mother liquor C. Fraction B is an aqueous solution of formic acid. The aqueous solution of formic acid is subjected to subsequent separation or application. Mother liquor C is concentrated sulfuric acid and sodium metavanadate.的catalysis system;

3) Add a small amount of DMSO and water required for the reaction to mother liquor C, and then heat to 50-95°C and stir for five minutes to one hour to fully combine to obtain active mother liquor D;

Among them, add 0.1-0.5mL DMSO per 1g biomass or domestic waste;

4) Put the biomass or domestic waste of the same quality as in step 1) in the active mother liquor D, and conduct oxidative hydrolysis at 2.0-7.0MPa and 140-170°C to quantitatively convert cellulose and hemicellulose into formic acid solution , Get oxidized hydrolysate.
A method for producing formic acid from biomass with high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO according to claim 1, characterized in that the oxidized hydrolysate obtained in step 4) is added to the oxidized hydrolysed solution A of step 2), Circulate steps 2), 3), and 4) to realize the circulation of the system.
The method for producing formic acid from biomass with high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO according to claim 1, wherein the biomass is wheat straw, corn straw, rice straw or reed stalk.
The method for producing formic acid from biomass with high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO according to claim 1, wherein the domestic waste is bagasse, cardboard paper or waste newspaper.
The method for producing formic acid from biomass with high-efficiency circulation of vanadium and sulfuric acid with trace DMSO according to claim 1, characterized in that the oxidative hydrolysis in step 1) and step 4) is carried out in oxygen or air.
The method for producing formic acid from biomass with high-efficiency circulation of vanadium and sulfuric acid in a trace of DMSO according to claim 1, wherein the added water in step 3) is distilled circulating water.