METHOD OF PRODUCING CARBAMIDE-FORMALDEHYDE CONCENTRATE Russian patent published in 2019 - IPC C08G12/12 

FIELD: technological processes.

SUBSTANCE: invention relates to a method of producing carbamide-formaldehyde concentrate. Method comprises chemosorption of formaldehyde formed during oxidative dehydration of methanol on an iron-molybdenum catalyst in a tubular or a shelf type reactor, by 50–65 % water solution of carbamide in neutral or weakly alkaline medium in three-section column with simultaneous removal of contaminated with methanol and formaldehyde water from its upper section. Irrigation of the exhaust gas flow in the upper section is carried out with demineralised water at temperature of 18–22 °C, obtained on an ammonia bromide-cooling refrigeration machine by supplying steam thereto with pressure of up to 1.2 MPa from a heat recovery boiler of an exothermic reaction of oxidising methanol to formaldehyde with simultaneous use of cold produced by it for conditioning commercial carbamide-formaldehyde concentrate to temperature of 23–25 °C.

EFFECT: invention enables to obtain a carbamide-formaldehyde concentrate with high storage stability, low buffer capacity and fewer waste water.

1 cl, 1 dwg, 2 tbl, 3 ex