Process for producing 5-hydroxymethylfurfural in the presence of an organic dehydration catalyst and a chloride source
The invention relates to a novel process for converting a feedstock comprising at least one sugar into 5-hydroxymethylfurfural, wherein said feedstock is brought into contact with one or more organic dehydration catalysts and one or more chloride sources in the presence of at least one aprotic polar solvent alone or as a mixture, at a temperature of between 30° C. and 200° C., and at a pressure of between 0.1 MPa and 10 MPa.
1. A process for converting a feedstock comprising at least one sugar into 5-hydroxymethylfurfural, which comprises bringing said feedstock into contact with at least one organic dehydration catalyst independently chosen from homogeneous and heterogeneous organic Brønsted acids, and at least one chloride source in the presence of at least one aprotic polar solvent, at a temperature of between 30° C. and 200° C. and a pressure of between 0.1 and 10 MPa,
wherein the chloride source is:
an organic cation of the guanidium family chosen from compounds of formula (IIIb)
wherein the groups R 5 to R 10 , which may be identical or different, are independently chosen from alkyl groups comprising between 1 and 20 carbon atoms, and aryl groups comprising between 5 and 20 carbon atoms, or
an organic cation of the phosphonium family chosen from compounds of formula (IIIc)
wherein R 11 to R 14 , which may be identical or different, are independently chosen from
alkyl groups, comprising between 1 and 20 carbon atoms,
aryl groups, comprising between 5 and 20 carbon atoms, and
phosphazene groups of general formula
wherein R 15 is an alkyl group comprising from 1 to 10 carbon atoms, and q is an integer between 0 and 10.
2. The process as claimed in claim 1 , wherein the feedstock is chosen from oligosaccharides and monosaccharides, alone or as a mixture.
3. The process as claimed in claim 1 , wherein the feedstock is chosen from sucrose, lactose, maltose, isomaltose, inulobiose, melibiose, gentiobiose, trehalose, cellobiose, cellotriose, cellotetraose and oligosaccharides resulting from the hydrolysis of said polysaccharides resulting from the hydrolysis of starch, inulin, cellulose or hemicellulose, alone or as a mixture.
4. The process as claimed in claim 1 , wherein the dehydration catalyst is an organic Brønsted acid chosen from the organic acids of general formulae R′COOH, R′SO 2 H, R′SO 3 H, (R′SO 2 )NH, (R′O) 2 PO 2 H, R′OH, wherein R′ is chosen from
alkyl and alkanol groups comprising from 1 to 20 carbon atoms,
aryl and heteroaryl groups preferably comprising between 4 and 20 carbon atoms, and
a hydrogen when the acid chosen corresponds to general formula R′COOH.
5. Process as claimed in claim 1 , wherein the dehydration catalyst is a heterogeneous organic Brønsted acid chosen from sulfonic acid resins, carbons functionalized with sulfonic and/or carboxylic groups, and silicas functionalized with sulfonic and/or carboxylic groups.
6. The process as claimed in claim 1 , wherein the chloride source is an organic cation of the guanidium family chosen from compounds of formula (IIIb).
7. The process as claimed in claim 1 , wherein the chloride source is an organic cation of the phosphonium family chosen from compounds of formula (IIIc).
8. The process as claimed in claim 1 , wherein the aprotic polar solvent(s) are chosen from all the aprotic polar solvents of which the dipole moment expressed in Debye (D) is greater than or equal to 2.00.
9. The process as claimed in claim 1 , wherein at least one aprotic polar solvent, alone or as a mixture, is chosen from pyridine, butan-2-one, acetone, acetic anhydride, N,N,N′,N′-tetramethylurea, benzonitrile, acetonitrile, methyl ethyl ketone, propionitrile, hexamethylphosphoramide, nitrobenzene, nitromethane, N,N-dimethylformamide, N,N-dimethylacetamide, sulfolane, N-methylpyrrolidone, dimethyl sulfoxide, propylene carbonate and γ-valerolactone.
10. The process as claimed in claim 1 , wherein the feedstock is introduced into the process in a weight ratio of the solvent to the feedstock (solvent/feedstock) of between 0.1 and 200.
11. The process as claimed in claim 1 , wherein the organic dehydration catalyst(s) are introduced into the reaction chamber in a weight ratio of the feedstock to the catalyst (feedstock/catalyst) of between 1 and 1000.
12. The process as claimed in claim 1 , wherein the chloride source(s) are introduced into the reaction chamber in a weight ratio of the feedstock to the chloride source(s) (feedstock/chloride source(s)) of between 1 and 1000.