Recovery and purification of acetylene

Claim 1

THE REMOVAL OF ACETYLENES FROM A GAS STREAM CONTAINING ACETYLENE, HEAVY ACETYLENES, DIACETYLENE AND CARBON DIOXIDE WHICH COMPRISES CONTACTING SAID GAS STREAM WITH DIMETHYLFORMAMIDE SOLVENT TO REMOVE SUBSTANTIALLY ONLY DIACETYLENE FROM SAID STREAM, STRIPPING DIACETYLENE FROM SAID SOLVENT AND REMOVING DIACETYLENE AS A SEPARATE STREAM FROM THE SYSTEM, RETURNING THE STRIPPED SOLVENT TO SAID CONTACTING FOR REUSE, PASSING THE RESULTING SUBSTANTIALLY DIACETYLENE FREE GAS INTO CONTACT WITH DIMETHYLFORMAMIDE SOLVENT TO REMOVE SUBSTANTIALLY ALL THE ACETYLENES THEREFROM, THUS OBTAINING AN ACETYLENE RICH SOLVENT STREAM, FRACTIONATING SAID ACETYLENE RICH SOLVENT STREAM TO REMOVE CARBON DIOXIDE THEREFROM, FLASHING THE RESULTANT RICH STREAM TO RECOVER AN ACETYLENE AND HEAVY ACETYLENES CONTAINING GAS STREAM AND SOLVENT, RETURNING THE SOLVENT FOR REUSE IN THE SYSTEM, CONTACTING THE ACETYLENE AND HEAVY ACETYHLENES CONTAINING GAS STREAM WITH HEPTANE TO HEAVY ACETYLENE FROM A SOLVENT RICH IN HEAVY ACETYLENES SAND RECOVERING, FINALLY, THE HEAVY ACETYLENES FROM THE SAID SOLVENT.