Process for the Preparation of 5-Hydroxymethylfurfural (HMF)

A process for the preparation of 5-hydroxymethylfurfural (HMF), having the following steps:

• provision or preparation of a starting mixture, comprising one, two or more starting compounds selected from the group consisting of hexoses, oligosaccharides comprising hexose units, and polysaccharides comprising hexose units, one, two or more organic salts with a melting point <180° C. and a boiling point >200° C. at 1013.25 hPa,
• optionally additionally one or more catalysts for the conversion of the one starting compound or at least one of the two or more starting compounds to 5-hydroxymethylfurfural (HMF), optionally water,
• optionally further substances,
• adjustment of first reaction conditions in the starting mixture, such that a first amount of the one starting compound or at least one of the two or more starting compounds converts to HMF and thus forms an intermediate product mixture, where the temperature under the first reaction conditions is in the range from 100 to 160° C.
• adjustment of second reaction conditions in a mixture which comprises the intermediate product mixture or a fraction of the intermediate product mixture, such that an amount of the intermediate product mixture converts to HMF and thus forms a product mixture, where the temperature under the second reaction conditions is in the range from 165 to 250° C., with HMF being separated off from the product mixture during this conversion.