Method of separating phenolic compounds in salified form

摘要

The subject of the present invention is a method for separating phenolic compounds in salified form from a reaction medium comprising them. The method of the invention for separating phenolic compounds in salified form from an aqueous reaction medium resulting from the reaction of a phenolic compound and of glyoxylic acid in the presence of a base leading to a reaction medium comprising at least the excess of initial phenolic compound in salified form and the various mandelic compounds in salified form resulting from the reaction, is characterized by the fact that said reaction medium is brought into contact with a basic anion-exchange resin that leads to the selective attachment of the initial phenolic compound to said resin and to the recovery of an aqueous stream comprising the mandelic compounds in salified form resulting from the reaction, and that the phenolic compound in salified form attached to the resin is separated by a resin regeneration treatment.

主权项

1. A method of separating a phenolic compound in salified form from an aqueous reaction mixture resulting from a reaction of a phenolic compound and glyoxylic acid in the presence of a base,
wherein the reaction mixture comprises excess phenolic compound in salified form and at least one mandelic compound in salified form, and said phenolic compound in salified form is a compound of formula (I), wherein:
R is an alkyl or alkoxy group having from 1 to 4 carbon atoms, or a halogen atom;x is an integer from 0 to 3; andM is a group (IA) alkali metal cation or an ammonium cation; said method comprising:
contacting said reaction mixture with a basic anion-exchange resin,
wherein the phenolic compound in salified form selectively attaches to said resin,recovering an aqueous stream comprising the at least one mandelic compound in salified form, andseparating the phenolic compound in salified form that is attached to the resin by a regenerative treatment of the resin which comprises treatment with a base.