An active material useful in an oxidative dehydrogenation reactor system has an active phase, a support phase, and an intermediate composite phase. The active phase includes a transition metal oxide such as manganese oxide, which is reversibly oxidizable and/or reducible between oxidized and reduced states. The support phase includes an oxide of a IUPAC Group 2-14 element. The composite phase is a mixed metal oxide of the transition metal and the Group 2-14 element. The active phase can also include a promoter such as Na-W04 and/or a selectivity modifier such as A1 or ceria. Also, a reactor including the active material in a reactor, a method of making the active material, and a method of using the active material in a regenerative reaction process.