A promising copper based oxygen carrier produced using industrially-relevant manufacturing equipment has been aged in IFPEN's 10 kW(th) Chemical Looping Combustion pilot plant. Methane combustion was performed at 900 degrees C for 160 h with an OC/fuel ratio of 1.2. While full methane conversion to CO2 and water was achieved in the early stage of the experiment, fast deactivation was observed. The oxygen carrying particles were thoroughly characterized at various stages of the ageing experiment, from which a pathway leading to deactivation is proposed.