Study on activity, stability limit and reaction mechanism of CO self-sustained combustion over the LaMnO3, La0.9Ce0.1MnO3 and La0.9Sr0.1MnO3 perovskite catalysts using sugar agent

The LaMnO3, La0.9Ce0.1MnO3 and La0.9Sr0.1MnO3 catalysts are synthesized using sugar agent, the CO self-sustained combustion is investigated, where catalytic performance decided by temperature with conversions of 10% (T10), 50% (T50), 90% (T90). results show that self-sustaining successfully realized on catalyst, order activity decrease as follows: (with sugar) > LaMnO3 (without sugar). Combined XPS, H2-TPR, O2-TPD CO-TPD techniques, excellent can be attributed to high content Mn4+ ions reactive oxygen vacancies enriched catalyst surface, sound low-temperature reduction, uniform dispersion. Besides, in situ IR spectroscopy indicate over manganese-based perovskite follows L-H mechanism: chemisorption O2 takes place produce monodentate carbonates bicarbonate species, which then decompose yield CO2 release. high-temperature stability test provides evidence gives 100% conversion activities remain almost unchanged after reaction for 12 h, bed reaches about 717 °C. obtained helpful accept this technology efficient clean energy utilization iron steel industry.