The present disclosure provides methods for isolating a long chain dicarboxylic acid such as a substantially pure or pure long chain dicarboxylic acid from a fermentation broth containing microbial cells.

The present disclosure provides methods for isolating a long chain dicarboxylic acid such as a substantially pure or pure long chain dicarboxylic acid from a fermentation broth containing microbial cells.

The present disclosure provides methods for isolating a long chain dicarboxylic acid such as a substantially pure or pure long chain dicarboxylic acid from a fermentation broth containing microbial cells.

Provided is a process for preparing azelaic acid.

Provided is a process for preparing azelaic acid.

Provided is a process for preparing azelaic acid.

A refining method according to the present invention is a refining method for crystallizing a compound with at least one crystal form, including setting, as a target wavelength and a target concentration, a specific infrared wavelength and a specific concentration at which a specific crystal form precipitates from a solution of the compound dissolved in a solvent, and using an infrared radiation apparatus capable of emitting infrared radiation including the target wavelength to evaporate the solvent and precipitate the specific crystal form while irradiating a solution of the compound dissolved in the solvent at the target concentration with infrared radiation including the target wavelength.

A refining method according to the present invention is a refining method for crystallizing a compound with at least one crystal form, including setting, as a target wavelength and a target concentration, a specific infrared wavelength and a specific concentration at which a specific crystal form precipitates from a solution of the compound dissolved in a solvent, and using an infrared radiation apparatus capable of emitting infrared radiation including the target wavelength to evaporate the solvent and precipitate the specific crystal form while irradiating a solution of the compound dissolved in the solvent at the target concentration with infrared radiation including the target wavelength.

The invention related to a method for purifying a first fatty acid, preferably polyunsaturated, using an initial mixture further comprising at least one second fatty acid, optionally a third fatty acid and optionally a fourth fatty acid, with the method comprising: a first step of chromatographic separation in liquid phase, using the initial mixture, carried out in a first unit for chromatographic separation, making it possible to recover on the one hand a first flow enriched with a first fatty acid and on the other hand a flow enriched with a second fatty acid, optionally, a second step of chromatographic separation in liquid phase, using the first flow enriched with a first fatty acid, carried out in a second chromatographic separation unit, making it possible to recover on the one hand a second flow enriched with a first fatty acid and on the other hand a flow enriched with a third fatty acid; optionally, a third step of chromatographic separation in liquid phase, using the third flow enriched with a first fatty acid, carried out in a third chromatographic separation unit, making it possible to recover on the one hand a third flow enriched with a first fatty acid and on the other hand a flow enriched with a fourth fatty acid; at least one among the first unit for chromatographic separation, the second unit for chromatographic separation and the third unit for chromatographic separation being a static bed chromatographic separation unit with a single column with recycling in stationary state.

The invention relates to a method for purifying a first fatty acid, in particular a first polyunsaturated fatty acid, using an initial mixture further comprising at least one second fatty acid and a third fatty acid, with the method comprising at least: a first step of chromatographic separation in liquid phase, using the initial mixture, making it possible to recover on the one hand a first flow enriched with a first fatty acid and on the other hand a flow enriched with a second fatty acid; a second step of chromatographic separation in liquid phase, using the first flow enriched with a first fatty acid, making it possible to recover on the one hand a second flow enriched with a first fatty acid and on the other hand a flow enriched with a third fatty acid, with the second step of chromatographic separation being carried out in a static bed chromatographic separation unit.