Method for determining relative amount of oxygen containing gas in a gas mixture

Claim 1

A method employing an electrochemical oxygen pumping device for measuring the relative amount of a measurement gas consisting essentially of at least one oxygen containing gas in a gas mixture comprising in addition at least a second oxygen containing gas which is capable of being pumped out of said device or disassociated at a voltage less than that which is capable of disassociating said measurement gas, said method comprising the steps of: providing communication between said gas mixture and a single restricted volume of an electrochemical device, which device comprises: a first solid electrochemical oxygen pump cell having a first pair of opposed electrodes; a second solid electrochemical oxygen pump cell having a second pair of opposed electrodes; a supporting structure coupled to said first and second pump cells to form with them said single restricted volume; at least one aperture for providing communication between said single restricted volume and said gas mixture; applying and maintaining a first voltage across said first pump cell to negatively bias a first pump cell electrode of said first pair of opposed electrodes inside said single restricted volume (i) sufficiently to cause substantially all said second oxygen containing gas molecules inside said single restricted volume to be pumped out from said single restricted volume or disassociated by a current flowing through said first pump cell and (ii) insufficiently to disassociate the measurement gas; applying and maintaining simultaneously with the maintaining of said first voltage, a second voltage across said second pump cell to negatively bias a second pump cell electrode of said second pair of opposed electrodes inside said single restricted volume sufficiently to disassociate only substantially all said measurement gas inside said single restricted volume by a current flowing through said second pump cell; and measuring said current flowing through said second pump cell, said second pump cell current being proportional to the relative amount of said measurement gas in said gas mixture.

Claim 2

A method employing an electrochemical oxygen pumping device for measuring the relative amount of a measurement gas consisting essentially of at least one oxygen containing gas in a gas mixture comprising in addition at least a second oxygen containing gas which is capable of being pumped out of said device or disassociated at a voltage less than that which is capable of disassociating said measurement gas, said method comprising the steps of: providing communication between said gas mixture and a single restricted volume of an electrochemical device, which device comprises: a first solid electrochemical oxygen pump cell having a first pair of opposed electrodes; a second solid electrochemical oxygen pump cell having a second pair of opposed electrodes; a supporting structure coupled to said first and second pump cells to form with them said single restricted volume; at least one aperture for providing communication between said single restricted volume and said gas mixture; applying and maintaining a first voltage across said first pump cell to negatively bias a first pump cell electrode of said first pair of opposed electrodes inside said single restricted volume (i) sufficiently to cause substantially all said second oxygen containing gas molecules inside said single restricted volume to be pumped out from said single restricted volume or disassociated by a current flowing through said first pump cell and (ii) insufficiently to disassociate the measurement gas; applying and maintaining simultaneously with the maintaining of said first voltage, a second voltage across said second pump cell to negatively bias a second pump cell electrode of said second pair of opposed electrodes inside said single restricted volume sufficiently to disassociate only substantially all said measurement gas inside said single restricted volume by a current flowing through said second pump cell; and measuring said current flowing through said second pump cell, said second pump cell current being proportional to the relative amount of said measurement gas in said gas mixture.

Claim 8

A method employing an electrochemical oxygen pumping device for measuring the relative amount of a measurement gas consisting essentially of at least one oxygen containing gas in a gas mixture comprising in addition at least a second oxygen containing gas which is capable of being pumped out of said device or disassociated at a voltage less than that which is capable of disassociating said measurement gas, said method comprising the steps of: providing communication between said gas mixture and a single volume of an electrochemical device, which device comprises: a first solid electrochemical oxygen pump cell having a first pair of opposed electrodes; a second solid electrochemical oxygen pump cell having a second pair of opposed electrodes; a supporting structure coupled to said first and second pump cells to form with them said single volume; at least one aperture for providing communication between said single volume and said gas mixture; applying a first voltage across said first pump cell to negatively bias a first pump cell electrode of said first pair of opposed electrodes inside said single volume (i) sufficiently to cause substantially all said second oxygen containing gas molecules inside said single volume to be pumped out from said single volume or disassociated by a current flowing through said first pump cell and (ii) insufficiently to disassociate the measurement gas; applying a second voltage across said second pump cell to negatively bias a second pump cell electrode of said second pair of opposed electrodes inside said single volume sufficiently to disassociate only substantially all said measurement gas inside said single volume by a current flowing through said second pump cell; and measuring said current flowing through said second pump cell, said second pump cell current being proportional to the relative amount of said measurement gas in said gas mixture.

Claim 9

A method employing an electrochemical oxygen pumping device for measuring the relative amount of a measurement gas consisting essentially of at least one oxygen containing gas in a gas mixture comprising in addition at least a second oxygen containing gas which is capable of being pumped out of said device or disassociated at a voltage less than that which is capable of disassociating said measurement gas, said method comprising the steps of: providing communication between said gas mixture and a single volume of an electrochemical device, which device comprises: a first solid electrochemical oxygen pump cell having a first pair of opposed electrodes; a second solid electrochemical oxygen pump cell having a second pair of opposed electrodes; a supporting structure coupled to said first and second pump cells to form with them said single volume; at least one aperture for providing communication between said single volume and said gas mixture; applying a first voltage across said first pump cell to negatively bias a first pump cell electrode of said first pair of opposed electrodes inside said single volume (i) sufficiently to cause substantially all said second oxygen containing gas molecules inside said single volume to be pumped out from said single volume or disassociated by a current flowing through said first pump cell and (ii) insufficiently to disassociate the measurement gas; applying a second voltage across said second pump cell to negatively bias a second pump cell electrode of said second pair of opposed electrodes inside said single volume sufficiently to disassociate only substantially all said measurement gas inside said single volume by a current flowing through said second pump cell; and measuring said current flowing through said second pump cell, said second pump cell current being proportional to the relative amount of said measurement gas in said gas mixture.