CO₂reforming of methane over highly active La-promoted Ni supported on SBA-15 catalysts: mechanism and kinetic modelling

Abstract

Various Ni catalysts were synthesized by combining a high surface area SBA-15 support, a novel preparation method using an oleic acid precursor to obtain highly dispersed and small Ni particles, and the basic property of La. The activity test shows that the La-promoted Ni/SBA-15 catalyst has much higher catalytic activity and stability than unpromoted Ni/SBA-15 catalysts in the CO 2 (dry) reforming of methane (DRM) reaction due to the crucial role of La to simultaneously adsorb CO 2 and remove deposited carbon from the Ni metal surface. The optimization of La content shows that only a small amount of La around 1 wt% is necessary to achieve the best catalytic performance. The reaction mechanism was then proposed and kinetic modeling (for pilot scale) was performed to find the rate-determining step (RDS) in the DRM reaction for this 1% La-promoted Ni/SBA-15 catalyst. The obtained fitting result shows that CH 4 decomposition is the RDS for this catalyst with an apparent activation energy of around 40.8 kJ mol −1 which is similar to the activation energies reported for common Ni-based supported catalysts.Catal. Sci. Technol. This journal is

Promoting Effect of CeO2and MgO for CO2Reforming of Methane over Ni-ZnO Catalyst

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Employing a Nickel‐Containing Supramolecular Framework as Ni Precursor for Synthesizing Robust Supported Ni Catalysts for Dry Reforming of Methane

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Stability evaluation of ethanol dry reforming on Lanthania‐doped cobalt‐based catalysts for hydrogen‐rich syngas generation

“…The absence of La 2 O 3 peaks in X‐ray diffractograms could be attributed to the well‐dispersed La 2 O 3 particles with nano‐size outside the XRD functioning limit in line with other studies. It is well‐known that XRD measurement is not capable of detecting crystals smaller than 5 nm …”