TREATMENT OF FORMALDEHYDE-CONTAINING MIXTURES Russian patent published in 2003 - IPC

FIELD: chemical technology. SUBSTANCE: invention relates to the improved method for removal of formaldehyde or it adducts from liquid organic mixture obtained in production of methylmethacrylate. Mixture contains at least carboxylic acid or carboxylic acid ester and formaldehyde or it adducts that forms biphase mixture with water. Method involves at least one extraction of liquid organic mixture in system liquid-liquid using water as an extractant to obtain flow of organic phase and flow of aqueous phase. Flow of organic phase contains significantly reduced concentration of formaldehyde or it adducts as compared with liquid organic mixture. Invention relates also to method for preparing methylmethacrylate with removal of formaldehyde or it adducts from prepared liquid organic mixture. Method provides reducing formaldehyde content in product flow of methylmethacrylate up to less 0.5 wt.-%. EFFECT: improved treatment method. 14 cl, 5 tbl, 1 dwg