Separation of gaseous mixtures including argon

Claim 1

METHOD OF OBTAINING HIGH PURITY ARGON FROM A GASEOUS MIXTURE INCLUDING OXYGEN, NITROGEN AND ARGON WHICH COMPRISES PASSING OVER A CATALYST COMPRESSED GASEOUS MIXTURE AND QUANTITY OF HYDROGEN IN EXCESS OF THE STOICHIOMETRIC AMOUNT REQUIRED FOR A CATLYTIC REACTION WITH THE OXYGEN OF THE GASEOUS MIXTURE TO FORM WATER TO PROVIDE A REACTION PRODUCT INCLUDING WATER, ARGON, HYDROGEN AND NITROGEN, REMOVING WATER FROM THE REACTION PRODUCT, COOLING THE REACTION PRODUCT, SEPARATING THE RACTION PRODUCT UNDER HIGH PRESSURE AND RELATIVELY LOW TEMPERATURE IN A FIRST FRACTIONING ZONE PRODUCING FIRST HIGH BOILING LIQUID FRACTION AND FIRST LOW BOILING POINT GASEOUS FRACTION, THE FIRST HIGH BOILING POINT LIQUID FRACTION COMPRISING ARGON AND NITROGEN AND THE FIRST LOW BOILING FRACTION CONTAINING SUBSTANTIALLY THE TOTAL HYDROGEN CONTENT OF THE GASEOUS MIXTURE, SEPARATING FIRST HIGH BOILING POINT LIQUID FRACTION UNDER LOW PRESSURE IN A SECOND FRACTIONATING ZONE PRODUCING SECOND HIGH BOILING LIQUID FRACTION AND SECOND LOWBOILING GASEOUS FRACTION, THE SECOND HIGH BOILING POINT LIQUID FRACTION COMPRISING HIGH PURITY ARGON AND THE SECOND LOW BOILING POINT GASEOUS FRACTION CONTAINING SUBSTANTIALLY THE TOTAL NITROGEN OF THE GASEOUS MIXTURE, ESTABLISHING HEAT INTERCHANGE BETWEEN SECOND HIGH BOILING POINT LIQUID FRACTION AND FIRST LOW BOILING POINT GASEOUS FRACTION TO LIQUEFY FIRST LOW BOILING POINT GASEOUS FRACTION AS REFLUX FOR THE FIRST FRACTIONATING ZONE, WITHDRAWING SECOND HIGH BOILING LIQUID FRACTION FROM THE SECOND FRACTIONATING ZONE, EXPANDING WITHDRAWN SECOND HIGH BOILING POINT LIQUID FRACTION TO RELATIVELY LOW PRESSURE, PASSING EXPANDED SECOND HIGH BOILING POINT FRACTION IN HEAT EXCHANGE EFFECTING RELATION WITH SECOND LOW BOILING POINT GASEOUS FRACTION TO VAPORIZE EXPANDED SECOND HIGH BOILING POINT FRACTION AND EFFECT PARTIAL LIQUEFACTION OF SECOND GASEOUS LOW BOILING POINT FRACTION, SEPARATING THE LIQUEFIED PORTION OF THE SECOND LOW BOILING POINT FRACTION FROM THE UNLIQUEFIED PORTION OF THE SECOND LOW PORTION POINT FRACTION, RETURNING THE LIQUEFIED PORTION OF THE SECOND LOW BOILING POINT FRACTION TO THE SECOND FRACTIONATING ZONE AS REFLUX, SUBJECTING THE UNLIQUEFIED PORTION OF THE SECOND LOW BOILING POINT FRACTION TO FURTHER SEPARATION IN A THIRD FRACTIONATING ZONE TO PRODUCE A THIRD HIGH BOILING FRACTION AND A THIRD LOW BOILING POINT GASEOUS FRACTION, PASSING COOL COMPRESSED GASEOUS MATERIAL IN HEAT EXCHANGE RELATION WITH FIRST HIGH BOILING POINT IN LIQUID FRACTION TO VAPORIZE FIRST HIGH BOILING POINT FRACTION AS REBOIL FOR THE FIRST FRACTIONATING ZONE AND FURTHER COOL THE GASEOUS MATERIAL, EXPANDING FURTHER COOL GASEOUS MATERIAL TO A RELATIVELY LOW PRESSURE, PASSING EXPANDED GASEOUS MATERIAL IN HEAT INTERCHANGE WITH THIRD GASEOUS LOW BOILING POINT FRACTION TO LIQUEFY THIRD GASEOUS LOW BOILING POINT FRACTION AS REFLUX FOR THE THIRD FRACTIONATING ZONE, PASSING EXPANDED GASEOUS MATERIAL AFTER THE LAST-NAMED HEAT INTERCHANGE IN HEAT INTERCHANGE WITH COOL GASEOUS MATERIAL PRIOR TO ITS EXPANSION AND THEREAFTER WARMING, COMPRESSING AND COOLING THE GASEOUS MATERIAL TO PROVIDE SAID COOL COMPRESSED GASEOUS MATERIAL, UTILIZING THIRD LIQUID HIGH BOILING POINT FRACTION AS REFLUX FOR THE SECOND FRACTIONATING ZONE, AND PASSING VAPORIZED EXPANDED SECOND BOILING POINT FRACTION AND BOILING POINT FRACTION IN HEAT INTERCHANGE WITH THE GASEOUS MIXTURE.