Method for separating mandelic compounds in salified form and use of same for preparing aromatic aldehyde

摘要

The invention describes a method for separating a mandelic compound in salified form from an aqueous reaction medium resulting from the condensation reaction of a hydroxylated aromatic compound with glyoxylic acid in a basic medium, said method comprising a) decanting said reaction medium in such a way as to recover an organic phase formed from the excess of said aromatic compound and an aqueous phase formed from said mandelic compound and a quantity of the excess of said aromatic compound and b) bringing said aqueous phase into contact with an adsorbent support, resulting in the selective adsorption of said aromatic compound and the recovery of an aqueous flow comprising said mandelic compound in salified form, which is subjected to an oxidation step before being converted into hydroxyaromatic aldehyde by electrodialysis.

主权项

1. A process for separating at least one mandelic compound in salified form from an aqueous reaction mixture resulting from condensation, in a basic aqueous medium, of at least one aromatic compound bearing at least one hydroxyl group and in which the para position is free with glyoxylic acid, said process comprising:
a) decanting said reaction medium to recover an organic phase comprising aromatic compound in non-salified form and an aqueous phase comprising the at least one mandelic compound and an amount of the aromatic compound, each in salified form, b) contacting said aqueous phase with an adsorbent support to selectively adsorb aromatic compound from the aqueous phase on said support and recover an aqueous mixture comprising the at least one mandelic compound in salified form.