Evaluation of Fe-containing LiCuO on CO capture performed at different physicochemical conditions.

LiCuO and different iron-containing LiCuO samples were synthesized by solid state reaction. On iron-containing samples, atomic sites of copper are substituted by iron ions in the lattice (XRD and Rietveld analyses). Iron addition induces copper release from LiCuO, which produce cationic vacancies and CuO, due to copper (Cu) and iron (Fe) valence differences. Two different physicochemical conditions were used for analyzing CO capture on these samples; (i) high temperature and (ii) low temperature in presence of water vapor. At high temperatures, iron addition increased CO chemisorption, due to structural and chemical variations on LiCuO. Kinetic analysis performed by first order reaction and Eyring models evidenced that iron addition on LiCuO induced a faster CO chemisorption but a higher thermal dependence. Conversely, CO chemisorption at low temperature in water vapor presence practically did not vary by iron addition, although hydration and hydroxylation processes were enhanced. Moreover, under these physicochemical conditions the whole sorption process became slower on iron-containing samples, due to metal oxides presence.