A process for producing hydrogen comprising reacting at least one hydrocarbon and steam in the presence of a complex metal oxide and a steam-hydrocarbon reforming catalyst in a production step under reaction conditions sufficient to form hydrogen and a spent complex metal oxide, wherein the complex metal oxide is represented by the formula (A′xCax′Mgx″)x(B′yMny′Fey″)yOn where A′ represents at least one element selected from the group consisting of Sr, Ba, a Group 1 element, and an element of the Lanthanide series according to the IUPAC Periodic Table of the Elements; B′ represents at least one element selected from the group consisting of Cu, Ni, Co, Cr, and V; 0≦x≦1, 0≦x′≦1, 0≦x″≦1 wherein x+x′+x″=x; 0≦y≦1, 0≦y′≦1, 0≦y″≦1 wherein y+y′+y″=y; 1≦x≦10; 1≦y≦10; and n represents a value such that the complex metal oxide is rendered electrically neutral.