Method of removing oxygen from gases

Claim 1

A METHOD FOR REMOVING OXYGEN BY CHEMISORPTION FROM A GAS SELECTED FROM THE GROUP CONSISTING OF HYDROCARBONS, ETHER, NITROGEN, ARGON, NEON, KRYPTON, XENON, AND CARBON DIOXIDE, SAID METHOD COMPRISING CONTACTING SAID GAS WITH AN ACTIVATED MASS INCLUDING AN IMPREGNATED HEAT PROOF OXIDIX CARRIER, SAID CARRIER HAVING A SURFACE AREA OF ABOUT 200 TO ABOUT 500 M2/GM, SAID IMPREGNATED CARRIER BEING OBTAINED BY IMPREGNATING SAID CARRIER WITH AN AQUEOUS SOLUTION OF CRO3 OR A CHROMIUM SALT TO OBTAIN AN AIR-DRY IMPREGNATED CARRIER HAVING A CHROMIUM CONTENT BY WEIGHT OF ABOUT 15 TO ABOUT 5%, SAID MASS BEING ACTIVATED BY TREATMENT WITH OXYGEN AT A TEMPERATURE FROM ABOUT 300*C TO ABOUT 600*C FOR A PERIOD OF TIME OF ABOUT 30 MINUTES TO ABOUT 240 MINUTES AND SUBSEQUENTLY BEING REDUCED WITH CARBON MONOIXDE OR HYDROGEN AT A TEMPERATURE IN THE RANGE OF ABOUT 250*C TO ABOUT 400*C BUT AT A TEMPERATURE BELOW SAID ACTIVATING TEMPERATURE FOR A PERIOD OF TIME OF ABOUT 5 MINUTES TO ABOUT 60 MINUTES WHEREBY THE CHROMIUM IN SAID IMPREGNATED CARRIER IS CHANGED FROM 6-VALUE CHROMIUM TO BIVALENT CHROMIUM.

Claim 2

A METHOD FOR REMOVING OXYGEN BY CHEMISORPTION FROM A GAS SELECTED FROM THE GROUP CONSISTING OF HYDROCARBONS, ETHER, NITROGEN, ARGON, NEON, KRYPTON, XENON, AND CARBON DIOXIDE, SAID METHOD COMPRISING CONTACTING SAID GAS WITH AN ACTIVATED MASS INCLUDING AN IMPREGNATED HEAT PROOF OXIDIX CARRIER, SAID CARRIER HAVING A SURFACE AREA OF ABOUT 200 TO ABOUT 500 M2/GM, SAID IMPREGNATED CARRIER BEING OBTAINED BY IMPREGNATING SAID CARRIER WITH AN AQUEOUS SOLUTION OF CRO3 OR A CHROMIUM SALT TO OBTAIN AN AIR-DRY IMPREGNATED CARRIER HAVING A CHROMIUM CONTENT BY WEIGHT OF ABOUT 15 TO ABOUT 5%, SAID MASS BEING ACTIVATED BY TREATMENT WITH OXYGEN AT A TEMPERATURE FROM ABOUT 300*C TO ABOUT 600*C FOR A PERIOD OF TIME OF ABOUT 30 MINUTES TO ABOUT 240 MINUTES AND SUBSEQUENTLY BEING REDUCED WITH CARBON MONOIXDE OR HYDROGEN AT A TEMPERATURE IN THE RANGE OF ABOUT 250*C TO ABOUT 400*C BUT AT A TEMPERATURE BELOW SAID ACTIVATING TEMPERATURE FOR A PERIOD OF TIME OF ABOUT 5 MINUTES TO ABOUT 60 MINUTES WHEREBY THE CHROMIUM IN SAID IMPREGNATED CARRIER IS CHANGED FROM 6-VALUE CHROMIUM TO BIVALENT CHROMIUM.

Claim 3

A method of removing oxygen by chemisorption from an oxygen containing gas, comprising bringing said gas into contact with a mass consisting essentially of a heat proof oxidic carrier having a surface area of about 200 to about 500 square meters per gram and containing on the surface of saId carrier about 1 to about 5 percent by weight of chromium in the form of a lower chromium oxide, said mass having been activated prior to said contact by treatment with oxygen at a temperature of about 300* to about 600* C to form a higher chromiumoxide and subsequent reduction of said higher chromium oxide to said lower chromium oxide by contact with a reducing gas at a temperature lower than said activation temperature.

Claim 4

A method of removing oxygen by chemisorption from an oxygen containing gas, comprising bringing said gas into contact with a mass consisting essentially of a heat proof oxidic carrier having a surface area of about 200 to about 500 square meters per gram and containing on the surface of saId carrier about 1 to about 5 percent by weight of chromium in the form of a lower chromium oxide, said mass having been activated prior to said contact by treatment with oxygen at a temperature of about 300* to about 600* C to form a higher chromiumoxide and subsequent reduction of said higher chromium oxide to said lower chromium oxide by contact with a reducing gas at a temperature lower than said activation temperature.