Abstract: Provided herein is a process for preparing furan-2,5-dicarboxylic acid. The process includes the following steps: (A-1) preparing a starting mixture comprising one, two or more carbohydrate compounds selected from the group consisting of: hexoses, oligosaccharides comprising hexose units, and polysaccharides including hexose units, and as a solvent or as a co-solvent for the carbohydrate compounds an amount of one or more carboxylic acid esters of a formula (II) and (A-2) subjecting the starting mixture to reaction conditions so that at least one of the one, two or more carbohydrate compounds reacts, and a fraction of the amount of one or more carboxylic acid esters of formula (II) is hydrolyzed, resulting in a mixture including 5-(hydroxymethyl)furfural and/or the one or more HMF esters of a formula (I), one or more carboxylic acids of a formula (III) and a remaining fraction of the amount of one or more carboxylic acid esters of formula (II).

Abstract: A process for preparing furan-2,5-dicarboxylic acid is disclosed. The process includes the following steps: preparing or providing a starting mixture including 5-(hydroxy-methyl)furfural (HMF), 5,5?-[oxy-bis(methylene)]bis-2-furfural (di-HMF), and water; subjecting said starting mixture to oxidation conditions in the presence of an oxygen-containing gas and a catalytically effective amount of a heterogeneous catalyst including one or more noble metals on a support so that both HMF and di-HMF react to give furane-2,5-dicarboxylic acid in a product mixture also including water and oxidation by-products. The use of a catalyst is also disclosed, the catalyst including one or more noble metals on a support as an heterogeneous oxidation catalyst for catalyzing in an aqueous starting mixture the reaction of both HMF and di-HMF to furane-2,5-dicarboxylic acid.

Abstract: Provided herein is a process for preparing a mixture including 5-(hydroxy-methyl)furfural (HMF) and one or more HMF esters of formula (I), the process including the following steps: (A-1) preparing or providing a starting mixture which includes one, two or more carbohydrate compounds and as the solvent or as a co-solvent for the carbohydrate compounds an amount of one or more carboxylic acid esters of formula (II); (A-2) subjecting the starting mixture to reaction conditions so that at least one of the one, two or more carbohydrate compounds reacts, and a fraction of the amount of one or more carboxylic acid esters of formula (II) is hydrolyzed, so that a mixture results that includes 5-(hydroxy-methyl)furfural and/or the one or more HMF esters of formula (I), one or more carboxylic acids of formula (III) and a remaining fraction of the amount of one or more carboxylic acid esters of formula (II).

Abstract: Provided herein is a process for preparing a mixture including 5-(hydroxy-methyl)furfural (HMF) and one or more HMF esters of formula (I), the process including the following steps: (A-1) preparing or providing a starting mixture which includes one, two or more carbohydrate compounds and as the solvent or as a co-solvent for the carbohydrate compounds an amount of one or more carboxylic acid esters of formula (II); (A-2) subjecting the starting mixture to reaction conditions so that at least one of the one, two or more carbohydrate compounds reacts, and a fraction of the amount of one or more carboxylic acid esters of formula (II) is hydrolyzed, so that a mixture results that includes 5-(hydroxy-methyl)furfural and/or the one or more HMF esters of formula (I), one or more carboxylic acids of formula (III) and a remaining fraction of the amount of one or more carboxylic acid esters of formula (II).

Abstract: Provided herein is a process for preparing furan-2,5-dicarboxylic acid. The process includes the following steps: (A-1) preparing a starting mixture comprising one, two or more carbohydrate compounds selected from the group consisting of: hexoses, oligosaccharides comprising hexose units, and polysaccharides including hexose units, and as a solvent or as a co-solvent for the carbohydrate compounds an amount of one or more carboxylic acid esters of a formula (II) and (A-2) subjecting the starting mixture to reaction conditions so that at least one of the one, two or more carbohydrate compounds reacts, and a fraction of the amount of one or more carboxylic acid esters of formula (II) is hydrolyzed, resulting in a mixture including 5-(hydroxymethyl)furfural and/or the one or more HMF esters of a formula (I), one or more carboxylic acids of a formula (III) and a remaining fraction of the amount of one or more carboxylic acid esters of formula (II).

Abstract: A process for preparing furan-2,5-dicarboxylic acid is disclosed. The process includes the following steps: preparing or providing a starting mixture including 5-(hydroxy-methyl)furfural (HMF), 5,5?-[oxy-bis(methylene)]bis-2-furfural (di-HMF), and water; subjecting said starting mixture to oxidation conditions in the presence of an oxygen-containing gas and a catalytically effective amount of a heterogeneous catalyst including one or more noble metals on a support so that both HMF and di-HMF react to give furane-2,5-dicarboxylic acid in a product mixture also including water and oxidation by-products. The use of a catalyst is also disclosed, the catalyst including one or more noble metals on a support as an heterogeneous oxidation catalyst for catalyzing in an aqueous starting mixture the reaction of both HMF and di-HMF to furane-2,5-dicarboxylic acid.