PROCESS FOR RECOVERY AND RECUPERATION OF TRIFLUOROMETHANE FROM GAS MIXTURE Russian patent published in 1997 - IPC

FIELD: chemical industry. SUBSTANCE: production of difluorochloromethane (coolant 22) for recovery of trifluoromethane (coolant 23) from outgoing gases. Said coolant is ozone safe coolant and dry etching coolant. Process comprises adding coolant 22 to original gas mixture which comprises, in addition to coolant 23, nitrogen, oxygen and carbon monoxide till coolant 22 content is the mixture reaches 1 or 50 mole% preferably 20-40 mole%. The mixture is thereafter squeezed to 9-30 atm, cooled to minus 25-35 C, condensed, and condensate is separated from uncondensable gas. The condensate is rectified to isolate trifluoromethane as the desired fraction, and the stillage fraction consisting substantially of coolant 22 is used for addition to the original gas mixture. The claimed process makes it possible to obtain 90% recovery of trifluoromethane from gas mixture. 2 cl, 1 tbl. EFFECT: more efficient recovery process. 2 cl, 1 tbl