METHOD FOR DISTILLATION PURIFICATION OF DIARYL CARBONATES Russian patent published in 2013 - IPC C07C68/06 C07C69/96 B01D3/14 C07C68/08 

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method for distillation purification of diaryl carbonates of general formula (I) where R, R' and R" independently represent a hydrogen atom, a straight-chain or branched alkyl with 1-34 carbon atoms, an alkoxy with 1-34 carbon atoms, a cycloalkyl with 5-34 carbon atoms, an alkylaryl with 7-34 carbon atoms, an aryl with 6-34 carbon atoms or a halogen radical. R, R' and R" on both sides of formula (I) can be identical or different, and R can also denote -COO-R"', wherein R'" can represent a hydrogen atom; an alkyl with 1-34 carbon atoms, an alkoxy with 1-34 carbon atoms, a cycloalkyl with 5-34 carbon atoms, an alkylaryl with 7-34 carbon atoms or an aryl with 6-34 carbon atoms, in at least one distillation column, having at least one enriching part in the top part of the column and at least one distillation part in the bottom part of the column, where the diaryl carbonate to be purified is obtained by re-esterification of at least one dialkyl carbonate and at least one aromatic hydroxyl-containing compound of general formula (III) where R, R' and R" can independently assume values given or general formula (I), in the presence of at least one re-esterification catalyst and which contains as an impurity, a catalyst used to produce diaryl carbonate, and the purified diaryl carbonate is removed in the side stream of the first distillation column, the first distillation column being a column with a dividing wall.

EFFECT: easy to implement method provides energy-efficient removal of catalyst residues and impurities of high-boiling secondary components.

15 cl, 3 ex, 11 dwg