Effect of honeycomb supporting on activity of LaBO3±δ perovskite-like catalysts for methane flameless combustion

The activity of honeycomb supported LaBO3 +/-delta (B = Fe, Mn and Cc) and La2NiO4 was tested for the catalytic flameless combustion (CFC) of methane and compared with their catalytic behaviour in powder form. Catalyst supporting brought about some modifications, mainly the complete loss of the suprafacial activity. Furthermore, thermal resistance of supported samples was checked through accelerated deactivation tests and showed to strongly depend on the nature of the B ion. Structural and morphological properties of fresh and aged catalysts, both in powder form (either pure or mixed with the primer precursor) and as honeycomb-supported samples, were compared to investigate the effect of each step of the dip-coating procedure. This allowed to shed light on the causes of the structural and chemical changes occurring during the wash-coating and leading to more or less severe decrease of performance and of thermal resistance of the final catalyst. (c) 2005 Elsevier B.V. All rights reserved.