Abstract: The invention relates to a method for the isomerization of glucose into fructose in water in the presence of a solid base catalyst characterized by its reversibility of CO2 adsorption at a low temperature, the catalyst being a catalyst comprising at least one supported or non-supported lanthanide oxide or a molecular sieve based on silicon containing the organic template thereof. The invention also relates to a method for preparing HMF from glucose, comprising the isomerization of glucose into fructose.

Abstract: A method for preparing 2,5-furandicarboxylic acid (FDCA) by oxidizing 5-hydroxymethylfurfural (HMF) in water in the presence of a weak base and a supported catalyst comprising platinum and bismuth, in which the Bi/Pt molar ratio in the catalyst is between 0.1 and 0.3, and preferably between 0.15 and 0.3.

Abstract: A method for preparing at least one ester of levulinic acid from a biomass includes steps of impregnating the biomass by an organic or inorganic acid, and putting the acidified biomass in contact with a supercritical fluid including at least one olefin.

Abstract: A method for preparing a dialkyloxydianhyrohexitol (dimethylisosorbide) composition by etherification of dianhydrohexitol (isosorbide). The aim is to achieve a “clean” method that avoids the use of a methylation agent such as dimethyl sulfate or methyl chloride, which generates stoechiometric quantities of salts, or expensive dialkyl-carbonates, wherein only one of the two methyl groups participates in the preparation of mixed isosorbide ethers. The method involves using at least one O-alkylation agent and a catalyst including an acid or an acid salt, preferably a catalyst having Lewis or BrØnsted acid properties. A device for carrying out the method wherein the device includes a vaporization oven and a reaction oven is also described.

Abstract: A method for synthesizing a composition comprising at least one acid ester stemming from the biomass and an organic biosolvent is provided. The method comprises the esterification reaction between at least one acid stemming from the biomass and at least one alcohol, in the presence of an acid catalyst and of the organic biosolvent, the organic biosolvent being selective of the ester or of the esters formed relatively to the acid or to the starting acids and non-miscible with the alcoholic solution of the acid stemming from the biomass.

Abstract: The invention relates to a method for preparing 5-hydroxymethylfurfural (HMF) by reacting hexose in water and in the presence of carboxylic acid. The present invention further relates to the preparation of 5-hydroxymethylfurfural (HMF) by reacting hexose in water and in the presence of carboxylic acid and of a heterogenous acid catalyst. The invention also relates to an HMF-rich carboxylic acid solution.

Abstract: A method for preparing 2,5-furandicarboxylic acid (FDCA) by oxidizing 5-hydroxymethylfurfural (HMF) in water in the presence of a weak base and a supported catalyst comprising platinum and bismuth, in which the Bi/Pt molar ratio in the catalyst is between 0.1 and 0.3, and preferably between 0.15 and 0.3.

Abstract: The invention relates to a method for preparing furfural by reacting pentose in water and in the presence of carboxylic acid and of a heterogeneous acid catalyst, the method being conducted in an aqueous solution of carboxylic acid as a reaction medium. The present invention also relates to the preparation of furfural by reaction of pentose in water and in the presence of carboxylic acid and of a heterogeneous acid catalyst. The invention also relates to an aqueous solution of carboxylic acid rich in furfural.

Abstract: A method for preparing a dialkyloxydianhyrohexitol (dimethylisosorbide) composition by etherification of dianhydrohexitol (isosorbide). The aim is to achieve a “clean” method that avoids the use of a methylation agent such as dimethyl sulfate or methyl chloride, which generates stoechiometric quantities of salts, or expensive dialkyl-carbonates, wherein only one of the two methyl groups participates in the preparation of mixed isosorbide ethers. The method involves using at least one O-alkylation agent and a catalyst including an acid or an acid salt, preferably a catalyst having Lewis or BrØnsted acid properties. A device for carrying out the method wherein the device includes a vaporization oven and a reaction oven is also described.

Abstract: A method for preparing at least one ester of levulinic acid from a biomass includes steps of impregnating the biomass by an organic or inorganic acid, and putting the acidified biomass in contact with a supercritical fluid including at least one olefin.

Abstract: The invention relates to a method for the isomerisation of glucose into fructose in water in the presence of a solid base catalyst characterised by its reversibility of CO2 adsorption at a low temperature, the catalyst being a catalyst comprising at least one supported or non-supported lanthanide oxide or a molecular sieve based on silicon containing the organic template thereof. The invention also relates to a method for preparing HMF from glucose, comprising the isomerisation of glucose into fructose.

Abstract: The invention relates to a process for transformation of lignocellulosic biomass or cellulose using stable non-zeolitic heterogeneous catalysts that are based on tin and/or antimony, preferably dispersed on a substrate. The use of these catalysts makes it possible to obtain directly lactic acid with high selectivity while limiting the production of oligosaccharides and soluble polymers.

Abstract: The invention relates to a process for transformation of lignoceliulosic biomass or cellulose that uses tungsten-oxide-based heterogeneous catalysts that are dispersed on an oxide-based substrate, preferably with a base of oxide(s) of aluminum and/or zirconium and/or titanium and/or niobium and containing an element in the particular metallic state. The use of these catalysts makes it possible to obtain directly upgradable products containing three carbon atoms, in particular hydroxyacetone and propylene glycol with high selectivity.

Abstract: The invention relates to a method for preparing furfural by reacting pentose in water and in the presence of carboxylic acid and of a heterogeneous acid catalyst, the method being conducted in an aqueous solution of carboxylic acid as a reaction medium. The present invention also relates to the preparation of furfural by reaction of pentose in water and in the presence of carboxylic acid and of a heterogeneous acid catalyst. The invention also relates to an aqueous solution of carboxylic acid rich in furfural.

Abstract: The invention relates to a process for transformation of lignocellulosic biomass or cellulose using heterogeneous catalysts that are based on tin oxide and/or antimony oxide, dispersed on a substrate and containing at least one element in the particular metal state. The use of these catalysts makes it possible to obtain directly upgradable products, in particular hydroxyacetone and propylene glycol with high selectivity.

Abstract: The invention relates to a method for preparing 5-hydroxymethylfurfural (HMF) by reacting hexose in water and in the presence of carboxylic acid. The present invention further relates to the preparation of 5-hydroxymethylfurfural (HMF) by reacting hexose in water and in the presence of carboxylic acid and of a heterogenous acid catalyst. The invention also relates to an HMF-rich carboxylic acid solution.

Abstract: The invention relates to a method of preparing a mixture of biofuels comprising fatty acid esters and at least one mixture of glycerol ethers from fatty substances that may contain free fatty acids and ethanol comprising: a) a step of transesterification of a vegetable or animal oil by ethanol in the presence of a catalyst based on at least one alkali metal salt or ammonium heteropolyacid salt characterized by differential heat of adsorption of ammonia which is greater than or equal to 150 kJ/mol, stable at T>150.degree. C., in order to obtain fatty acid esters and glycerol, and, b) a step of etherification of the glycerol formed during step a) by the alcohol used in step a) in the presence of the catalyst from step a) in order to obtain at least one ether of the glycerol, said steps a) and b) taking place simultaneously, in one and the same reactor.

Abstract: The invention relates to a process for transformation of lignocellulosic biomass or cellulose that uses tungsten-based heterogeneous catalysts that are dispersed on an oxide-based substrate, preferably with a base of oxide(s) of aluminum and/or zirconium and/or titanium and/or niobium. The use of these catalysts makes it possible to obtain directly lactic acid with high selectivity while limiting the production of oligosaccharides and soluble polymers.

Abstract: The invention relates to a process for transformation of lignocellulosic biomass or cellulose using stable non-zeolitic heterogeneous catalysts that are based on tin and/or antimony, preferably dispersed on a substrate. The use of these catalysts makes it possible to obtain directly lactic acid with high selectivity while limiting the production of oligosaccharides and soluble polymers.

Abstract: The invention relates to a process for transformation of lignocellulosic biomass or cellulose using heterogeneous catalysts that are based on tin oxide and/or antimony oxide, dispersed on a substrate and containing at least one element in the particular metal state. The use of these catalysts makes it possible to obtain directly upgradable products, in particular hydroxyacetone and propylene glycol with high selectivity.