US 12,662,376 B2
Method of separating phosgene and hydrogen chloride
Torsten Mattke, Ludwigshafen am Rhein (DE); Kai Thiele, Antwerp (BE); Jens Ferbitz, Ludwigshafen am Rhein (DE); Peter Van Den Abeel, Antwerp (BE); and Hans-Juergen Pallasch, Ludwigshafen am Rhein (DE)
Assigned to BASF SE, Ludwigshafen am Rhein (DE)
Appl. No. 18/277,415
Filed by BASF SE, Ludwigshafen am Rhein (DE)
PCT Filed Feb. 10, 2022, PCT No. PCT/EP2022/053214
§ 371(c)(1), (2) Date Aug. 16, 2023,
PCT Pub. No. WO2022/175152, PCT Pub. Date Aug. 25, 2022.
Claims priority of application No. 21157533 (EP), filed on Feb. 17, 2021.
Prior Publication US 2024/0300817 A1, Sep. 12, 2024
Int. Cl. C01B 7/07 (2006.01); B01D 53/00 (2006.01); C01B 32/80 (2017.01); C07C 263/20 (2006.01)
CPC C01B 7/0712 (2013.01) [B01D 53/002 (2013.01); C01B 7/0731 (2013.01); C01B 32/80 (2017.08); C07C 263/20 (2013.01); B01D 2256/26 (2013.01); B01D 2257/2064 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A process of separating phosgene and hydrogen chloride, comprising:
conveying a mixed stream containing hydrogen chloride and phosgene into a distillation column;
withdrawing from the distillation column a bottom stream containing phosgene;
withdrawing a top stream containing hydrogen chloride;
compressing at least a portion of the top stream and at least partially condensing the compressed top stream to form a liquid stream, decompressing at least a portion of the liquid stream to form a cooled liquid stream and a cooled gas stream; and
recycling the cooled liquid stream to the top of the distillation column as a reflux;
the process additionally comprising temporarily introducing an absorbing solvent into the distillation column, wherein the absorbing solvent is introduced at the top of the distillation column and/or into the reflux liquid.