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The purpose of the present study was to evaluate the ability of LaFeO3 perovskites prepared using the “self-combustion method” to behave as efficient and stable catalysts in phenol oxidation using H2O2 in ambient conditions. Depending on the synthesis conditions, strong differences in the structural, textural and reducibility characteristics of the perovskites, as well as in phenol conversion and TOC abatement level were observed. High TOC abatement (76%) and very low iron leaching (0.27 wt%) were obtained at 40 °C in the presence of LaFeO3 nanoparticles exhibiting the lowest crystal domain size. [ABSTRACT FROM AUTHOR]

Abstract: CO2 reforming of CH4 to synthesis gas was investigated on new grounds using Ni-containing phyllosilicates (PS) as catalyst precursors. Ni-containing 1:1 PS and 2:1 PS were synthesized hydrothermally from a gel containing sodium silicate and nickel chloride, then they were reduced under H2 flow before being used as catalysts. Several complementary techniques including XRD, TG-DTA, FTIR, and TPR were used to evaluate the structural, thermal, spectroscopic and redox properties of the samples, respectively. Ni 2:1 PS were found to be more thermally stable and catalytically active than Ni 1:1 PS. Well crystallized Ni 1:1 PS thermally treated at 700°C resulted in a transitional 2:1 PS phase. The reduction of structural nickel in thermally stable PS led to the formation of nanometric Ni0 particles over the surface of the remaining unreduced PS as well as on silica. The unreduced PS structure with surface OH groups appeared as one of the best supports for Ni0 nanoparticles, resulting in less coke formation, and thereby leading to a high catalytic stability. [ABSTRACT FROM AUTHOR]