METHOD OF PREPARING CARBIDOFORMALDEHYDRYDE CONCENTRATE Russian patent published in 2001 - IPC

FIELD: chemical industry. SUBSTANCE: described is method of preparing carbidoformaldehyde concentrate for treatment of carbamide, condensation of carbamide with formaldehyde in aqueous medium at molar ratio thereof of 1: (3.0- 6.5) by heating and at pH of medium from 6.5-8.5 followed by concentration of reaction mixture. Condensation of aqueous solution of formaldehyde and carbamide at pH of 6.5-8.5 is carried out for 10-60 minutes. Reaction mixture is neutralized and concentrated by heating under vacuum to residual water content of not higher then 20 wt %. EFFECT: prevention of caking of the desired product. 2 cl, 2 tbl