RU2583953C1 - Method of producing 5-hydroxyl methyl furfural - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to organic synthesis, specifically to method of production of 5-hydroxyl methyl furfural (5-GMF) using hydrolysis-dehydration of cellulose in aqueous medium at temperature not exceeding 180 °C in presence of mesoporous carbon material “Sibunit”, processed by oxidation of wet air mixture at temperatures higher than 400°C. 5-hydroxyl methyl furfural is promising raw material and is used for production of food additives, pharmaceutical preparations, polymer materials, liquid fuel and fuel additives.

EFFECT: technical result of such method is simple procedure for treatment of mesoporous carbon material “Sibunit”, reduction of environmental risks due to usage of non-toxic oxidizer and absence of washing procedure of catalyst from unreacted sulphuric acid.

1 cl, 1 tbl, 5 ex

Description

The invention relates to the field of organic synthesis, specifically to the production of 5-hydroxymethylfurfural (5-GMF), which is a promising raw material and is used for the production of food additives, pharmaceuticals, polymeric materials, liquid fuels and fuel additives.

The main methods for producing 5-GMF are the dehydration of hexose (containing six carbon atoms) sugars (monosaccharides), mainly glucose and fructose, catalyzed by soluble or solid acid catalysts in an aqueous-organic medium.

A known method for producing 5-hydroxymethylfurfural [RU 2363698, C07D 307/46, 08/10/2009] by acid-catalytic conversion of fructose in a two-phase water-organic extractant system at atmospheric pressure, where sodium hydrosulfate with the addition of sulfuric acid is used as a catalyst, and as dioxane is used in the extractant, and a method for producing 5-hydroxymethylfurfural through hexose dehydration [CN 103483298, C07D 307/48, 01/01/2014], which involves mixing hexose, carbon monoxide (graphite) as a catalyst and an organic solvent .

The main disadvantages of such methods is the use of saccharides having valuable food and feed values and toxic organic solvents as feedstock.

Non-food polysaccharide cellulose (glucose polymer) is one of the main components (up to 60%) of promising renewable lignocellulosic raw materials and can be used as an alternative source of 5-GMF production.

Known methods for producing 5-GMF from non-food raw materials - cellulose as a result of a single-stage process of hydrolysis-dehydration. Cellulose to hexoses is hydrolyzed with soluble mineral acids [JP 2007145736, C07D 307/46, 09/14/2012] at a temperature of 200 to 400 ° C or ionic liquids as a catalyst [CN 102675264, B01J 31/24, C07D 307/46, 09/19/19. 2012] at 130-170 ° C, glucose dehydration occurs under the same conditions.

The disadvantages of the first method are the use of corrosive mineral acids as catalysts, high temperature, as well as the rapid subsequent dehydration of 5-GMF to levulinic and formic acids. The disadvantage of the second is the use of environmentally hazardous and expensive ionic liquid.

The closest technical solution to the claimed method is the process of producing 5-GMF as a result of one-step hydrolysis-dehydration of cellulose in an aqueous medium at 180 ° C and in the presence of solid carbon catalysts from the commercial mesoporous carbon material "Sibunit-4" (Institute of Problems of Hydrocarbon Processing, g Omsk) obtained by sulfonation in concentrated steaming sulfuric acid at a temperature of from 90 ° C to 250 ° C [N.V. Gromov, O.P. Taran, D.A. Yatsenko, A.B. Ayupov, A. Loppine-Serani, S. Amoni, V.E. Agabekov. Development of sulfonated catalysts based on graphite-like carbon material sibunit for cellulose hydrolysis // Journal of Siberian Federal University. Chemistry. 2014.Vol. 1. No. 7. S. 87-99]. The yield of the target product reaches 21.5% when using a catalyst sulfonated at 200 ° C.

The main disadvantage of this method is the use of a catalyst, which must be prepared using fuming sulfuric acid, which is toxic (LD ₅₀ = 510 mg / kg), as well as corrosive.

Another disadvantage is the need to wash the catalyst with a large amount of distilled water from unreacted sulfuric acid, which leads to the formation of a large amount of environmentally hazardous wastewater.

The invention solves the problem of producing 5-HMP by one-stage hydrolysis — dehydration of cellulose in an aqueous medium using a solid catalyst that does not require fuming sulfuric acid for its production.

The problem is solved in that the preparation of 5-hydroxymethylfurfural is carried out by single-stage hydrolysis-dehydration of cellulose in an aqueous medium at a temperature not exceeding 180 ° C in the presence of a catalyst obtained from the Sibunit mesoporous carbon material treated by oxidation with a moist air mixture at temperatures above 400 ° C [O.P. Taran, E.M. Polyanskaya, O.L. Ogorodnikova, S. Descorme, M. Besson, V.N. Parmon. Catalysts based on the carbon material Sibunit for the deep oxidation of organic ecotoxicants in aqueous solutions. (one). Surface properties of oxidized Sibunit // Catalysis in industry. 2010. No.6. S. 48-54].

A comparative analysis of the invention with the prototype shows that the common features of the proposed method and prototype are:

- the use of cellulose as a raw material;

- carrying out the process in the aquatic environment;

- carrying out the process in an inert atmosphere.

A distinctive feature of the invention is:

- use as a catalyst of the carbon material "Sibunit", oxidized with moist air.

EFFECT: simplification of the method and procedure for processing the Sibunit mesoporous carbon material, as well as reduction of environmental risks due to the use of a non-toxic oxidizing agent and the absence of a procedure for washing the catalyst from unreacted sulfuric acid.

The invention is illustrated by the following examples.

Example 1

For the experiment, 6 g of cellulose and 6 g of catalyst, oxidized with moist air at 500 ° C, are placed in a high pressure autoclave reactor equipped with a mechanical stirrer with a magnetic drive, a heating and temperature control system with proportional-integral-differential (PID) adjustment and a sampling system, add 450 ml of water. The reactor is closed, purged with argon five times to remove air, an argon pressure of 10 atm is created and the reaction mixture begins to heat. After reaching a temperature of 180 ° C (the time to reach this temperature is approximately 30 minutes) include stirring. The reaction is carried out with vigorous stirring (1500 rpm). The content of cellulose and catalyst in the feed mixture is 10 g / l. The reaction is carried out for 5 hours. During the reaction, samples are taken from the autoclave periodically (after 1 hour) for analysis. Samples are filtered through an acetate-cellulose filter with a pore diameter of 0.22 μm. The concentration of the resulting 5-GMF is determined by high performance liquid chromatography. After 5 hours of reaction, its value is 1.79 g / l, which is 23.0 mol.% Per 10 g of cellulose.

5-GMF is extracted with isopropanol. The resulting solution was distilled in vacuo (2 mmHg). The structure of 5-GMF is confirmed by chromatography-mass spectrometry. As a result of the experiment, 1.04 g of 5-GMF is obtained, which is 22.4 mol%, calculated on 6 g of cellulose.

Example 2

Similar to example 1, but using a catalyst oxidized at 450 ° C. The concentration of the target product is 1.41 g / l (18.1 mol.%). Obtain 0.83 g of 5-GMF (17.8 mol.%).

Example 3

Similar to example 1, but using a catalyst oxidized at 400 ° C. The concentration of the target product is 1.37 g / l (17.6 mol.%). Obtain 0.79 g of 5-GMF (17.0 mol.%).

Example 4 (prototype)

The experiment is carried out with a catalyst oxidized by fuming sulfuric acid at 200 ° C [N.V. Gromov, O.P. Taran, D.A. Yatsenko, A.B. Ayupov, A. Loppine-Serani, S. Amoni, V.E. Agabekov. Development of sulfonated catalysts based on graphite-like carbon material sibunit for cellulose hydrolysis // Journal of Siberian Federal University. Chemistry. 2014.Vol. 1. No. 7. S. 87-99]. The reaction is carried out according to the method similar to example 1. After 5 hours of reaction, the concentration of the target product is 1.67 g / l, which is 21.5 mol.% Per 10 g of cellulose. Obtain 0.97 g of 5-GMF (20.9 mol%).

Example 5

Similar to Examples 1-4, but using the Sibunit untreated mesoporous carbon material as a catalyst. The concentration of the target product throughout the experiment remains below the detection limit of the analysis method used.

The table shows the product yields of the process of one-step hydrolysis-dehydration of cellulose in the presence of solid carbon catalysts detected by HPLC analysis of reaction mixtures. The reaction was carried out in the presence of different catalysts, but under the same conditions: the concentration of cellulose and catalyst was 10 g / l, the volume of the reaction mixture was 45 ml, the temperature was 180 ° С, the pressure was 10 atm, and the maximum reaction time was 5 h. The temperature of 180 ° С was optimal for conducting the process. With an increase or decrease in temperature by more than 10 ° С, the yields of 5-GMF decrease [N.V. Gromov, O.P. Taran, D.A. Yatsenko, A.B. Ayupov, A. Loppine-Serani, S. Amoni, V.E. Agabekov. Development of sulfonated catalysts based on graphite-like carbon material sibunit for cellulose hydrolysis // Journal of Siberian Federal University. Chemistry. 2014.Vol. 1. No. 7. S. 87-99]. Increased argon pressure is necessary to maintain the reaction system in a liquid state and to prevent oxidation of products with atmospheric oxygen.

Glucose is a product of the hydrolysis of cellulose, fructose and mannose — products of glucose isomerization, and it is fructose that passes into the target 5-GMF product as a result of the dehydration reaction, and mannose can rearrange to fructose. Levulinic and formic acids are products of further dehydration of 5-GMF.

As can be seen from the table, the use of the Sibunit mesoporous carbon material, oxidized with moist air, as a catalyst for the process of one-step hydrolysis-dehydration of cellulose in an aqueous medium makes it possible to obtain 5-GMF yields comparable to those obtained in the presence of a catalyst prepared from carbon material "Sibunit-4" boiling with steaming sulfuric acid, or even exceeding them. However, the processing of the catalyst occurs without the use of fuming sulfuric acid and the formation of a large amount of environmentally and corrosion hazardous wastewater. Other useful products of the process are monosaccharides (glucose, fructose and mannose), which after separation of 5-GMF can be used to produce bioethanol by biotechnological methods. In the presence of the raw carbon material Sibunit, the formation of 5-GMF and monosaccharides does not occur.

Claims (1)

The method of producing 5-hydroxymethylfurfural by single-stage hydrolysis-dehydration of cellulose in an aqueous medium at a temperature not exceeding 180 ° C and in the presence of a catalyst, characterized in that the catalyst used is Sibunit mesoporous carbon material treated by oxidation with a moist air mixture at temperatures above 400 ° C.