The oxidative properties of Li/MgO in the absence of O2 were studied at 730-degrees-C using C2H4 as a reducing agent and a multisectional flow stainless steel tubular reactor. Large amounts of CO and H-2 were determined. it was demonstrated that Li/MgO exhibited a high oxygen mobility. The exchange capacity was (2.4-4.0) x 10(20) oxygen atoms per 1 g of the catalyst and the period of oxygen donation was 150 h or more. After the catalyst reduction, its oxygen transfer ability was fully restored by re-oxidation in the stream of air. Oxidation Of C2H4 to CO and H-2 was accompanied by its decomposition to C and H-2. The ratio DELTAH-2/DELTAC2H4 was found to be 1.91 +/- 0.13 independently of the oxidation state of the catalyst, the location of the sampling point along the catalyst bed (and the post-catalytic zone) and the duration of the experiment. The mechanism was discussed.