Composite oxygen transport membrane

A method of producing a porous material comprising:

• forming a mixture of particles of (Ln1-xAx)wCr1-yByO3-δ and doped zirconia and that is substantially free of pore formers, where Ln is La, Y, Pr, Ce or Sm;
• A is Ca;
• B is Fe, Mn, Co, Al, Ti or combinations thereof;
• w is <0.9-1.1;
• x is 0.2-0.4 and y is 0.1-0.6;
• and
• sintering the first mixture in air at a temperature of <1300° C.;
• wherein the sintered first mixture contains (Ln1-xAx)wCr1-yByO3-δ and doped zirconia in a first volume ratio of between 1 to 4 and 4 to 1 on a volume percentile basis.

An oxygen ion composite membrane comprising:

• first and second layers on a porous support providing a porous fuel oxidation layer and a dense separation layer, respectively, for the oxygen ion composite membrane;
• each of the first and second layers containing a mixture of (Ln1-xAx)wCr1-yByO3-δ and doped zirconia, where for the first of the layers, Ln is La, Y, Pr, Ce or Sm;
• A is Ca;
• B is Fe, Mn, Co, Al, Ti or combinations thereof;
• w is <0.9-1.1;
• x is 0.1-0.4;
• and y is 0.1-0.6 and for the second of the layers, A is Sr;
• and B is Fe, Mn, Co, Al or combinations thereof;
• w is <0.9-1.1;
• x is 0.1-0.3;
• and y is 0.1-0.6;
• the first of the layers containing (Ln1-xAx)wCr1-yByO3-δ and doped zirconia in a first volume ratio of between 2 to 3 and 4 to 2 on a volume percentile basis;
• and the second of the layers containing (Ln1-xAx)wCr1-yByO3-δ and doped zirconia in a second volume ratio of between 1 to 4 and 3 to 2 on a volume percentile basis.