Method for producing an aqueous 5-hydroxymethylfurfural (5-hmf) solution

A process for producing an aqueous solution of 5-hydroxymethylfurfural (5-HMF), said process comprising the following steps:

• a step a) of placing a feedstock (1) comprising 5-HMF and dimethyl sulfoxide (DMSO) in contact with at least a fraction of an intermediate aqueous back-extract (9), advantageously obtained from step c), so as to obtain at least one aqueous mixture (3),
• a step b) of liquid-liquid extraction of the mixture (3) obtained on conclusion of step a) in the presence of an extraction solvent so as to produce an aqueous raffinate (5) and an intermediate organic extract (6), and then
• a step c) of backwashing with an aqueous solvent (7), so as to produce the intermediate aqueous back-extract (9) and an organic raffinate (8) comprising 5-HMF and an organic solvent,
• a step d) of concentrating the organic raffinate (8) obtained from step c) by removing at least part of the organic solvent, producing a concentrated organic extract (10), comprising 5-HMF, preferably in a content greater than or equal to 40% by weight, and residual organic solvent, preferably in a content less than or equal to 60% by weight, and a stream (11) comprising organic solvent,
• a hydrodistillation step e) performed by distilling the concentrated organic extract (10) obtained from step d) in the presence of water, to produce an aqueous solution (12) of 5-HMF and a stream (13) comprising organic solvent.