Patent ID: 7897128

Claim:
A process for making a complex metal oxide comprising the formula A x B y O z wherein A is at least one metallic element selected from the group consisting of elements of Groups 2, and 3, and the Lanthanide elements of the IUPAC Periodic Table of the Elements, which has an oxidation state ranging from +1 to +3; B is at least one metallic element having an oxidation state ranging from +1 to +7 selected from the group consisting of vanadium, chromium, manganese, iron, cobalt, copper, and nickel; O is an oxygen atom; x is a number from about 1 to about 10; y is a number greater than 0 and equal to or less than about 10 for each element B; and z is a number that renders the complex metal oxide substantially charge neutral, the process comprising the steps of: (a) reacting in a solution at a temperature of between about 75° C. to about 100° C. at least one water-soluble salt of A, at least one water-soluble salt of B and a stoichiometric amount of a carbonate salt or bicarbonate salt required to form each mole of a carbonate precipitate represented by the formula A x B y (CO 3 ) n wherein n is a number that renders the carbonate precipitate charge neutral, wherein the reacting is conducted in a substantial absence of carbon dioxide to form the carbonate precipitate and wherein the molar amount of carbonate salt or bicarbonate salt is at least three times the stoichiometric amount of carbonate or bicarbonate salt required to form each mole of the carbonate precipitate, and wherein the carbonate salt or bicarbonate salt is selected from the group consisting of NaHCO 3 , KHCO 3 , CsHCO 3 , Na 2 CO 3 , and K 2 CO 3 ; and (b) reacting the carbonate precipitate with an oxygen containing gas at a temperature of from between about 650° C. to about 1,200° C. to form the complex metal oxide.