Provided is a method for preparing levulinic acid using a solid acid catalyst in the presence of an ethylene glycol-based compound. The levulinic acid according to the present invention can be prepared by using a linear or cyclic ethylene glycol-based compound as a solvent and preparing the levulinic acid from fructose in the presence of the solid acid catalyst at a reaction temperature of 100 to 200 C., thereby reducing the dependency on petroleum in response to greenhouse gas emission regulations. Also, a high yield of levulinic acid can be obtained from fructose, and the solvent and the catalyst can be efficiently separated, collected, and reused after the reaction has completed.

Provided is a method for preparing levulinic acid using a solid acid catalyst in the presence of an ethylene glycol-based compound. The levulinic acid according to the present invention can be prepared by using a linear or cyclic ethylene glycol-based compound as a solvent and preparing the levulinic acid from fructose in the presence of the solid acid catalyst at a reaction temperature of 100 to 200 C., thereby reducing the dependency on petroleum in response to greenhouse gas emission regulations. Also, a high yield of levulinic acid can be obtained from fructose, and the solvent and the catalyst can be efficiently separated, collected, and reused after the reaction has completed.

Disclosed is the integration of the production of acetic anhydride from ketene, and the acetylation of wood using acetylation fluid comprising acetic acid and acetic anhydride. The invention involves recovering acetylation fluid from wood acetylation, and sending this to an acetic anhydride distillation unit belonging to the acetic anhydride production plant.

Disclosed is the integration of the production of acetic anhydride from ketene, and the acetylation of wood using acetylation fluid comprising acetic acid and acetic anhydride. The invention involves recovering acetylation fluid from wood acetylation, and sending this to an acetic anhydride distillation unit belonging to the acetic anhydride production plant.

Disclosed is the integration of the production of acetic anhydride from ketene, and the acetylation of wood using acetylation fluid comprising acetic acid and acetic anhydride. The invention involves recovering acetylation fluid from wood acetylation, and sending this to an acetic anhydride distillation unit belonging to the acetic anhydride production plant.

The invention relates to a method for separating a mixture containing at least one carboxylic acid vinyl ester of general formula RC(O)OCHCH.sub.2 and at least one carboxylic acid of general formula RCOOH, wherein R in either case can be an aliphatic group having 12 to 22 C atoms or a cycloaliphatic group having 12 to 22 C atoms, or an aromatic group having 12 to 22 C atoms, and R can be identical or different, characterized in that the carboxylic acid is converted to its anhydride RC(O)OC(O)R and the carboxylic acid vinyl ester is subsequently separated.

The invention relates to a method for separating a mixture containing at least one carboxylic acid vinyl ester of general formula RC(O)OCHCH.sub.2 and at least one carboxylic acid of general formula RCOOH, wherein R in either case can be an aliphatic group having 12 to 22 C atoms or a cycloaliphatic group having 12 to 22 C atoms, or an aromatic group having 12 to 22 C atoms, and R can be identical or different, characterized in that the carboxylic acid is converted to its anhydride RC(O)OC(O)R and the carboxylic acid vinyl ester is subsequently separated.

The invention relates to a method for separating a mixture containing at least one carboxylic acid vinyl ester of general formula RC(O)OCHCH.sub.2 and at least one carboxylic acid of general formula RCOOH, wherein R in either case can be an aliphatic group having 12 to 22 C atoms or a cycloaliphatic group having 12 to 22 C atoms, or an aromatic group having 12 to 22 C atoms, and R can be identical or different, characterized in that the carboxylic acid is converted to its anhydride RC(O)OC(O)R and the carboxylic acid vinyl ester is subsequently separated.

Methods and systems for the preparation of high purity and high quality cannabinoid acids and metal salts of cannabinoids. Cannabidiolic acid (CBDA) is a major cannabinoid of interest for and health reasons. It is the natural precursor of cannabidiol (CBD). The invention provides methods for the synthesis of CBDA from CBD with reagents that produce a high purity product without need for further purification. Insertion of a magnesium complexing agent prior to conversion of the reaction intermediate to the final acid product produces a high purity product with aesthetically pleasing white color and neutral odor. Methods are provided for the simultaneous synthesis and purification of cannabinoid acids, especially CBDA, produced from high purity CBD (or other cannabinoid) via a Kolbe-Schmitt type reaction using an organic base, such as DBU (1,8-diazabicyclo[5.4.0]undec-7-ene), incorporating complexation of acid anions to a multivalent metal, alkaline earth or transition metal, prior to product acid work-up. During the work-up to the final acid, the distinct solubility of the complex in selected solvents is used advantageously to first exclude water soluble reagents and impurities and next to exclude lipophilic hydroxyl-quinone impurities, as well as any unconverted CBD.

Methods and systems for the preparation of high purity and high quality cannabinoid acids and metal salts of cannabinoids. Cannabidiolic acid (CBDA) is a major cannabinoid of interest for and health reasons. It is the natural precursor of cannabidiol (CBD). The invention provides methods for the synthesis of CBDA from CBD with reagents that produce a high purity product without need for further purification. Insertion of a magnesium complexing agent prior to conversion of the reaction intermediate to the final acid product produces a high purity product with aesthetically pleasing white color and neutral odor. Methods are provided for the simultaneous synthesis and purification of cannabinoid acids, especially CBDA, produced from high purity CBD (or other cannabinoid) via a Kolbe-Schmitt type reaction using an organic base, such as DBU (1,8-diazabicyclo[5.4.0]undec-7-ene), incorporating complexation of acid anions to a multivalent metal, alkaline earth or transition metal, prior to product acid work-up. During the work-up to the final acid, the distinct solubility of the complex in selected solvents is used advantageously to first exclude water soluble reagents and impurities and next to exclude lipophilic hydroxyl-quinone impurities, as well as any unconverted CBD.