WO2021218669A1 - Procédé permettant de réaliser une circulation à haut rendement de vanadium et d'acide sulfurique avec des traces de dmso pour catalyser une biomasse afin de préparer de l'acide formique - Google Patents

Procédé permettant de réaliser une circulation à haut rendement de vanadium et d'acide sulfurique avec des traces de dmso pour catalyser une biomasse afin de préparer de l'acide formique Download PDF

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WO2021218669A1
WO2021218669A1 PCT/CN2021/087857 CN2021087857W WO2021218669A1 WO 2021218669 A1 WO2021218669 A1 WO 2021218669A1 CN 2021087857 W CN2021087857 W CN 2021087857W WO 2021218669 A1 WO2021218669 A1 WO 2021218669A1
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formic acid
biomass
dmso
mother liquor
oxidized
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PCT/CN2021/087857
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Chinese (zh)
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李洋
郭晏君
孙远利
张秀锋
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西安交通大学
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
    • B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
    • B01J27/053—Sulfates

Definitions

  • 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.
  • 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.
  • formic acid has attracted wide attention from scientists.
  • 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 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.
  • 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.
  • 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).
  • H 2 O 2 hydrogen peroxide
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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:
  • 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.
  • step 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.
  • step 1) and step 4) is carried out in oxygen or air.
  • the added water in step 3 is distilled circulating water.
  • 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.
  • 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.
  • 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).
  • Figure 1 is a schematic flow diagram of the present invention.
  • 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:
  • 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. ;
  • step 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:
  • 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. ;
  • step 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. %.
  • 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:
  • 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;
  • step 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. %.
  • 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:
  • 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);
  • 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. ;
  • 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:
  • 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);
  • 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. ;
  • 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:
  • 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);
  • 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. ;
  • 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:
  • 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. ;
  • 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:
  • 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);
  • 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. ;
  • 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:
  • 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. ;
  • 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:
  • 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. ;
  • 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:
  • 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);
  • 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. ;
  • 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:
  • 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. ;
  • 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:
  • 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);
  • 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. ;

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Processing Of Solid Wastes (AREA)

Abstract

L'invention concerne un procédé permettant de réaliser une circulation à haut rendement de vanadium et d'acide sulfurique avec des traces de DMSO pour catalyser une biomasse afin de préparer de l'acide formique. Le procédé comprend d'abord la mise en place d'une biomasse ou de déchets domestiques dans de l'acide sulfurique dilué, puis l'ajout de métavanadate de sodium et du DMSO pour l'oxydation et l'hydrolyse, de telle sorte que la cellulose et l'hémicellulose sont converties par quantification en acide formique, de manière à obtenir une solution d'oxydation et d'hydrolyse A ; puis la séparation de la solution d'oxydation et d'hydrolyse A au moyen d'une distillation à pression réduite pour obtenir une fraction B et une solution mère C, la fraction B étant une solution aqueuse de l'acide formique, qui est soumise à une séparation ou à une utilisation ultérieure ; puis l'ajout de DMSO et de l'eau dans la solution mère C, et le chauffage et l'agitation de ceux-ci pour les combiner afin d'obtenir une solution mère D active ; puis la mise en place d'une biomasse ou de déchets domestiques dans la solution mère active D pour l'oxydation et l'hydrolyse, de telle sorte que la cellulose et l'hémicellulose sont converties de manière quantitative en une solution d'acide formique, de façon à obtenir une solution d'oxydation et d'hydrolyse ; et enfin, l'ajout de la solution d'oxydation et d'hydrolyse dans la solution d'oxydation et d'hydrolyse A, et la répétition des étapes ci-dessus pour réaliser un cyclage du système. La présente invention a une bonne compatibilité, un rendement de préparation d'acide formique élevé, un post-traitement simple, et aucune diminution du rendement en acide formique après plusieurs cycles, ce qui réduit le coût et la pollution environnementale de celui-ci.
PCT/CN2021/087857 2020-04-29 2021-04-16 Procédé permettant de réaliser une circulation à haut rendement de vanadium et d'acide sulfurique avec des traces de dmso pour catalyser une biomasse afin de préparer de l'acide formique WO2021218669A1 (fr)

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