A process for the preparation of a saturated aliphatic carboxylic acid with 3 to 5 carbon atoms by oxidation of the corresponding aldehyde with oxygen in which (a) the corresponding aldehyde is converted with oxygen at a temperature of 40 to 150° C. and an oxygen partial pressure of 0.001 to 1 MPa to obtain a mixture containing the saturated aliphatic carboxylic acid and ≤2 mol-% of the corresponding aldehyde with respect to the saturated aliphatic carboxylic acid, (b) the mixture obtained in step (a) is thermally treated in the liquid phase at a temperature of 80 to 250° C. and a pressure of 0.1 to 2 MPa abs for 0.25 to 100 hours, and (c) the mixture obtained in step (b) is distilled in a distillation apparatus to obtain a distillate containing ≥90 wt.-% of the saturated aliphatic carboxylic acid and having an active oxygen content of 0 to 25 wt.-ppm based on the distillate.

A process for the preparation of a saturated aliphatic carboxylic acid with 3 to 5 carbon atoms by oxidation of the corresponding aldehyde with oxygen in which (a) the corresponding aldehyde is converted with oxygen at a temperature of 40 to 150° C. and an oxygen partial pressure of 0.001 to 1 MPa to obtain a mixture containing the saturated aliphatic carboxylic acid and ≤2 mol-% of the corresponding aldehyde with respect to the saturated aliphatic carboxylic acid, (b) the mixture obtained in step (a) is thermally treated in the liquid phase at a temperature of 80 to 250° C. and a pressure of 0.1 to 2 MPa abs for 0.25 to 100 hours, and (c) the mixture obtained in step (b) is distilled in a distillation apparatus to obtain a distillate containing ≥90 wt.-% of the saturated aliphatic carboxylic acid and having an active oxygen content of 0 to 25 wt.-ppm based on the distillate.

A process for the preparation of a saturated aliphatic carboxylic acid with 3 to 5 carbon atoms by oxidation of the corresponding aldehyde with oxygen in which (a) the corresponding aldehyde is converted with oxygen at a temperature of 40 to 150° C. and an oxygen partial pressure of 0.001 to 1 MPa to obtain a mixture containing the saturated aliphatic carboxylic acid and ≤2 mol-% of the corresponding aldehyde with respect to the saturated aliphatic carboxylic acid, (b) the mixture obtained in step (a) is thermally treated in the liquid phase at a temperature of 80 to 250° C. and a pressure of 0.1 to 2 MPa abs for 0.25 to 100 hours, and (c) the mixture obtained in step (b) is distilled in a distillation apparatus to obtain a distillate containing ≥90 wt.-% of the saturated aliphatic carboxylic acid and having an active oxygen content of 0 to 25 wt.-ppm based on the distillate.

Methods for the production of 2,4-dihydroxybutyrate (2,4-DHB) from erythrose and other four-carbon sugars are disclosed. The improved methods facilitate the production of 2,4-DHB that is a precursor for biorenewable and animal nutrition chemicals among others.

Methods for the production of 2,4-dihydroxybutyrate (2,4-DHB) from erythrose and other four-carbon sugars are disclosed. The improved methods facilitate the production of 2,4-DHB that is a precursor for biorenewable and animal nutrition chemicals among others.

There is provided a method for synthesizing an alkenoic acid, in particular acrylic acid comprising the step of oxidizing an alkenyl alcohol in the presence of a metal oxide catalyst to form the alkenoic acid. The invention further provides a step of deoxydehydrating a polyol, including glycerol to obtain said alkenyl alcohol including an allyl alcohol.

There is provided a method for synthesizing an alkenoic acid, in particular acrylic acid comprising the step of oxidizing an alkenyl alcohol in the presence of a metal oxide catalyst to form the alkenoic acid. The invention further provides a step of deoxydehydrating a polyol, including glycerol to obtain said alkenyl alcohol including an allyl alcohol.

Various processes for preparing aldaric acids, aldonic acids, uronic acids, and/or lactone(s) thereof are described. For example, processes for preparing a C.sub.2-C.sub.7 aldaric acid and/or lactone(s) thereof by the catalytic oxidation of a C.sub.2-C.sub.7 aldonic acid and/or lactone(s) thereof and/or a C.sub.2-C.sub.7 aldose are described.

Various processes for preparing aldaric acids, aldonic acids, uronic acids, and/or lactone(s) thereof are described. For example, processes for preparing a C.sub.2-C.sub.7 aldaric acid and/or lactone(s) thereof by the catalytic oxidation of a C.sub.2-C.sub.7 aldonic acid and/or lactone(s) thereof and/or a C.sub.2-C.sub.7 aldose are described.

Various processes for preparing aldaric acids, aldonic acids, uronic acids, and/or lactone(s) thereof are described. For example, processes for preparing a C.sub.2-C.sub.7 aldaric acid and/or lactone(s) thereof by the catalytic oxidation of a C.sub.2-C.sub.7 aldonic acid and/or lactone(s) thereof and/or a C.sub.2-C.sub.7 aldose are described.