Multilayer mixed oxide supported catalyst for oxidative coupling of methane

A multilayer supported oxidative coupling of methane (OCM) catalyst composition characterized by the general formula AaZbEcDdOx/support, wherein the multilayer supported OCM catalyst composition comprises a support, a first single oxide layer, one or more mixed oxide layers, and an optional second single oxide layer;

• wherein A is an alkaline earth metal;
• wherein Z is a first rare earth element;
• wherein E is a second rare earth element;
• wherein D is a redox agent or a third rare earth element;
• wherein the first rare earth element, the second rare earth element, and the third rare earth element, when present, are not the same;
• wherein a is 1.0;
• wherein b is from about 0.1 to about 10.0;
• wherein c is from about 0.1 to about 10.0;
• wherein d is from about 0 to about 10.0;
• wherein x balances the oxidation states;
• wherein the first single oxide layer contacts the support and the one or more mixed oxide layers, wherein the first single oxide layer is characterized by the general formula Zb1Ox1, wherein b1 is from about 0.1 to about 10.0;
• and wherein x1 balances the oxidation states;
• wherein the one or more mixed oxide layers contacts the first single oxide layer and optionally the second single oxide layer, wherein the one or more mixed oxide layers is characterized by the general formula Aa2Zb2Ec2Dd2Ox2, wherein a2 is 1.0;
• wherein b2 is from about 0.1 to about 10.0;
• wherein c2 is from about 0.1 to about 10.0;
• wherein d2 is from about 0 to about 10.0;
• wherein x2 balances the oxidation states;
• wherein the general formula AaZbEcDdOx and the general formula Aa2Zb2Ec2Dd2Ox2 are different;
• wherein the second single oxide layer, when present, contacts the one or more mixed oxide layers and optionally the first single oxide layer, and wherein the second single oxide layer is characterized by the general formula AO.