METHOD FOR PRODUCTION OF CONCENTRATED GASEOUS FORMALDEHYDE Russian patent published in 1996 - IPC

FIELD: organic chemistry. SUBSTANCE: method involves partial condensation of steam-gaseous mixture which contains formaldehyde, water, methanol and formic acid followed by separation of thus prepared condensed products and gaseous formaldehyde. Said condensation is carried out on the surface of heat conducting porous material which is cooled by water to temperature being lower than dew point of said steam-gaseous mixture. Cloth of natural or synthetic fiber or metallic sieves or porous polymer films are proposed as aforementioned porous material having pores 0.5-400 μm in size. Said condensation is carried out at 0.05-3.0 atm drop of pressure between steam-gaseous mixture and cooling liquid. EFFECT: increases yield of desired product, simplifies the method. 5 cl, 1 tbl