Method for purifying vanillin by liquid-liquid extraction

摘要

A method is described for purifying vanillin, and derivatives thereof, from an initial solution of vanillin or of a vanillin derivative in a solvent S1 containing impurities, comprising the following steps: a) a step of evaporating the solvent S1 in the presence of water from such initial solution to obtain an aqueous solution of vanillin or of a vanillin derivative; b) a step of liquid/liquid extraction by bringing the aqueous solution obtained at the end of step a) into contact with a solvent S2, at a pH of greater than 8 and less than 10, to obtain an organic phase and an aqueous phase containing vanillin or a vanillin derivative and residual solvent S2; c) a step of precipitating, at a pH between 4 and 7.5, the vanillin contained in the aqueous phase obtained at the end of step b); and d) a step of isolating the vanillin or derivative thereof.

主权项

1. A process for purifying vanillin and derivatives thereof, starting with an initial solution of vanillin or of a vanillin derivative in a solvent S1 containing impurities, comprising the following steps:
a) a step of evaporation of said solvent S1 in the presence of water from said initial solution of said vanillin or of said vanillin derivative containing said solvent S1 to obtain an aqueous solution of said vanillin or of said vanillin derivative; b) a step of liquid/liquid extraction by placing the aqueous solution obtained after step a) in contact with a solvent S2, at a pH greater than 8 and less than 10, to obtain an organic phase comprising said solvent S2 and an aqueous phase containing said vanillin or said vanillin derivative and residual solvent S2; c) a step of precipitation, at a pH of between 4 and 7.5, of said vanillin or said derivative contained in the aqueous phase obtained after step b), and d) a step of isolation of said vanillin or said derivative thereof.