公开(公告)号：US3606732A

公开(公告)日：1971-09-21

申请号：US3606732D

申请日：1968-11-04

Applicant: BASF AG

Inventor： WOERNER ALFRED ,  DUEMBGEN GERD ,  SPERBER HEINRICH ,  HAAS HANS ,  GRABOWSKY OTTO

IPC: C07C47/058 ,  C07C45/00 ,  C07C45/38 ,  C07C45/78 ,  C07C67/00 ,  B01D53/16

CPC classification number: C07C45/38 ,  C07C45/783 ,  C07C47/04

Abstract: A PROCESS FOR THE ABSORPTION OF FORMALDEHYDE FROM GAS CONTAINING FORMALDEHYDE (OBTAINED IN THE DEHYDROGENATING OXIDATION OF METHANOL OVER SILVER CATALYSTS) AT ELEVATED TEMPERATURE IN A PLURALITY OF STAGES, WHEREIN THE GAS PASSES THROUGH AT LEAST THREE ABSORPTION STAGES AT TEMPERATURES OF FROM 60* TO ABOUT 90*C., PAARICULARLY FROM 70* TO 85*C., AND IS CONTACTED IN EACH OF THE STAGES FROM THE FIRST STAGE TO THE PENULTIMATE STAGE WITH AN AQUEOUS SOLUTION OF A UREA-FORMALDEHYDE PRECONDENSATE AND IN THE FINAL STAGE IS CONTACTED WITH AN AQUEOUS SOLUTION OF UREA.