Continuous process for separating two gases having boiling temperatures which closely approach one another

Claim 1

A CONTINUOUS PROCESS FOR SEPARATING A GASEOUS MIXTURE OF TWO MATERIALS HAVING SUBSTANTIALLY CLOSE BOILING POINTS, COMPRISING INTIMATELY CONTACTING IN A FRACTIONATING COLUMN THE GASEOUS MIXTURE WITH A SOLVENT WHICH IS SELECTIVE WITH RESPECT TO SAID TWO MATERIALS, RECOVERING AS A FIRST SEPARATION PRODUCT ONE PORTION OF THAT OF SAID TWO MATERIALS WHICH IS LESS SOLUBLE IN SAID SELECTIVE SOLVENT AND IS DISCHARGED AT THE TOP OF SAID FRACTIONATING COLUMN, SUBJECTING THE SOLVENT EFFLUENT FROM SAID FRACTIONATING COLUMN CONTAINING SUBSTANTIALLY ALL OF THE MATERIAL WHICH IS MORE SOLUBLE IN SAID SOLVENT TO A DEGASSING PROCESS, RECOVERING AS A SECOND SEPARATION PRODUCT A PORTION OF THE GASEOUS RELEASE OF SAID DEGASSING PROCESS, RECYCLING A SECOND PORTION OF SAID GASEOUS RELEASE TO THE BOTTOM OF SAID FRACTIONATING COLUMN, ENTERING THE SOLVENT SOLUTION WHICH, AFTER SAID DEGASSING, CONTAINS A RESIDUAL PORTION OF SAID MATERIAL WHICH IS MORE SOLUBLE IN SAID SOLVENT NEAR THE TOP OF A STRIPPING COLUMN, PASSING IT, WITHIN SAID STRIPPING COLUMN, IN COUNTERCURRENT FLOW WITH A SECOND PORTION OF THAT OF SAID TWO MATERIALS WHICH IS LESS SOLUBLE IN SAID SELECTIVE SOLVENT AND IS DISCHARGED AT THE TOP OF SAID FRACTIONATING COLUMN, RECYCLING THE EFFLUENT OF SAID STRIPPING COLUMN TO THE TOP OF SAID FRACTIONATING COLUMN, AND RECYCLING THE GASEOUS MIXTURE OF SAID TWO MATERIALS WHICH IS DISCHARGED AT THE TOP OF SAID STRIPPING COLUMN IN CONTACT WITH UNTREATED MIXTURE OF SAID TWO GASEOUS MATERIALS WHICH IS ABOUT TO ENTER SAID FRACTIONATING COLUMN.