Unique methods have been developed to convert polysaccharides into value-added products, such as levulinic acid and alkyl levulinates. The polysaccharides are heated in the presence of water, an alcohol, and an acid to cleave the polysaccharide, and the resulting monosacchrides or monosaccharide acetals or both are contacted with an acid in the presence of an alcohol at a higher temperature. Useful acids include Brnsted acid catalysts and Lewis acid catalysts including mineral acids, metal halides, immobilized heterogeneous catalysts functionalized with a Brnsted acid group or a Lewis acid group, or combinations thereof.

Unique methods have been developed to convert polysaccharides into value-added products, such as levulinic acid and alkyl levulinates. The polysaccharides are heated in the presence of water, an alcohol, and an acid to cleave the polysaccharide, and the resulting monosacchrides or monosaccharide acetals or both are contacted with an acid in the presence of an alcohol at a higher temperature. Useful acids include Brnsted acid catalysts and Lewis acid catalysts including mineral acids, metal halides, immobilized heterogeneous catalysts functionalized with a Brnsted acid group or a Lewis acid group, or combinations thereof.

A method for producing levulinic acid from lignocellulosic biomass comprising hemicellulose including one or more six carbon chain compound precursors comprises the steps of hydrolyzing the lignocellulosic biomass to form a first phase comprising partially hydrolyzed lignocellulosic biomass including cellulose and lignin and a second phase comprising one or more five carbon chain sugars and one or more six carbon chain sugars from degradation of the hemicellulose, separating the first phase from the second phase, and converting at least a portion of the one or more six carbon chain sugars to levulinic acid.

A method for producing levulinic acid from lignocellulosic biomass comprising hemicellulose including one or more six carbon chain compound precursors comprises the steps of hydrolyzing the lignocellulosic biomass to form a first phase comprising partially hydrolyzed lignocellulosic biomass including cellulose and lignin and a second phase comprising one or more five carbon chain sugars and one or more six carbon chain sugars from degradation of the hemicellulose, separating the first phase from the second phase, and converting at least a portion of the one or more six carbon chain sugars to levulinic acid.

A process for the purification of levulinic acid including the following steps: a. providing a composition 1, comprising at least 75 wt. % of levulinic acid; b. cooling composition 1 to at least one temperature Tc, wherein Tc is a temperature in the range 1.23*(W1)104.5Tc ( C.)1.23*(W1)89.5, wherein W1 is the weight % of levulinic acid in composition 1, to obtain a cooled composition 1; c. performing melt crystallization of composition 1 including the steps of: i. bringing the cooled composition 1 into contact with levulinic acid crystal seeds, ii. allowing the levulinic acid in composition 1 to crystallize at at least one temperature Tc to obtain crystals 1 and liquid 1, and iii. draining of liquid 1; d. optionally, treating crystals 1, after draining of liquid 1, by sweating, according to the following steps: i. heating the crystals 1 at a temperature between 5 and 40 C. to obtain crystals 2 and liquid 2, and ii. draining of liquid 2; e. melting the crystals 1 or 2, after draining of liquid 1 or 2, to obtain composition 2, f. determining the levulinic acid concentration in composition 2 and, in case the levulinic acid concentration is below a predetermined value, repeating steps b, c, optionally d, and e, as many times as necessary to obtain a final composition with a predetermined levulinic acid concentration.

A process for the purification of levulinic acid including the following steps: a. providing a composition 1, comprising at least 75 wt. % of levulinic acid; b. cooling composition 1 to at least one temperature Tc, wherein Tc is a temperature in the range 1.23*(W1)104.5Tc ( C.)1.23*(W1)89.5, wherein W1 is the weight % of levulinic acid in composition 1, to obtain a cooled composition 1; c. performing melt crystallization of composition 1 including the steps of: i. bringing the cooled composition 1 into contact with levulinic acid crystal seeds, ii. allowing the levulinic acid in composition 1 to crystallize at at least one temperature Tc to obtain crystals 1 and liquid 1, and iii. draining of liquid 1; d. optionally, treating crystals 1, after draining of liquid 1, by sweating, according to the following steps: i. heating the crystals 1 at a temperature between 5 and 40 C. to obtain crystals 2 and liquid 2, and ii. draining of liquid 2; e. melting the crystals 1 or 2, after draining of liquid 1 or 2, to obtain composition 2, f. determining the levulinic acid concentration in composition 2 and, in case the levulinic acid concentration is below a predetermined value, repeating steps b, c, optionally d, and e, as many times as necessary to obtain a final composition with a predetermined levulinic acid concentration.

The invention relates generally to the preparation of hydroxymethyl furfural derivatives such as 5-carboxymethyl furfural derivatives, ethers such as 5-alkoxymethyl furfural derivatives, 5-hydroxymethyl furfural, levulinic acid, levulinic acid esters, and/or formic acid, formic acid esters from sugar.

The present invention relates to a novel integrated process to extract and purify levulinic acid (LA) produced from the technical lignin waste (2-G residue) generated after second generation (2-G) ethanol production from biomass. In this process, liquid-liquid extraction was carried out using fusel oil as an organic extractant to yield a LA rich organic phase and an acidic aqueous phase (raffinate). In addition, selected amines improved the LA yields by acting synergistically. Further fractional distillation was carried out to purify LA. The acidic raffinate is recycled back to the reaction in multiple times, which reduce the use of additional catalyst and make the overall process cost effective. The process is very simple and suitable to remove any colour and humins (soluble tar), which would otherwise form a problem in subsequent process step, particularly in distillation. At optimized process conditions 95% LA is recovered with 98% purity.

The present invention relates to a novel integrated process to extract and purify levulinic acid (LA) produced from the technical lignin waste (2-G residue) generated after second generation (2-G) ethanol production from biomass. In this process, liquid-liquid extraction was carried out using fusel oil as an organic extractant to yield a LA rich organic phase and an acidic aqueous phase (raffinate). In addition, selected amines improved the LA yields by acting synergistically. Further fractional distillation was carried out to purify LA. The acidic raffinate is recycled back to the reaction in multiple times, which reduce the use of additional catalyst and make the overall process cost effective. The process is very simple and suitable to remove any colour and humins (soluble tar), which would otherwise form a problem in subsequent process step, particularly in distillation. At optimized process conditions 95% LA is recovered with 98% purity.

The present invention relates to a novel integrated process to extract and purify levulinic acid (LA) produced from the technical lignin waste (2-G residue) generated after second generation (2-G) ethanol production from biomass. In this process, liquid-liquid extraction was carried out using fusel oil as an organic extractant to yield a LA rich organic phase and an acidic aqueous phase (raffinate). In addition, selected amines improved the LA yields by acting synergistically. Further fractional distillation was carried out to purify LA. The acidic raffinate is recycled back to the reaction in multiple times, which reduce the use of additional catalyst and make the overall process cost effective. The process is very simple and suitable to remove any colour and humins (soluble tar), which would otherwise form a problem in subsequent process step, particularly in distillation. At optimized process conditions 95% LA is recovered with 98% purity.