Improved performance of Ni/Al2O3 catalyst deriving from the hydrotalcite precursor synthesized on Al2O3 support for dry reforming of methane

Exploiting Ni-based catalysts with excellent catalytic activity and anti-coking ability is significant for dry reforming of CH4 with CO2 (DRM) which is a promising route to CO2 utilization. In this work, the Ni/Al2O3 catalyst with hydrotalcite precursor (NiAl-LDH) was synthesized by a facile in-situ growth method. And the effect of the NiAl-LDH structure on the catalytic activity and anti-coking ability of Ni/Al2O3 catalyst was revealed. The H-2-temperature programmed desorption (H-2-TPD) revealed that better Ni dispersion and more Ni-Al2O3 interface could be obtained by the NiAl-LDH precursor, which were vital for the activation of CH4 and CO2. Moreover, the NiAl-LDH precursor with non-LDH phase or turbostratic structure was also created by insufficient or extra amount of urea, and the obtained catalysts exhibited a poor catalytic stability, further confirming the importance of the LDH structure. In comparison with the Ni-IMP catalyst prepared by the conventional impregnation method, the CH4 conversion increased by 16% and the carbon deposition decreased by 75% over Ni-6 catalyst with well-organized LDH precursor under the same reaction conditions. Hence, this work represents an important step toward developing Ni-based catalysts with excellent catalytic activity and anti-coking ability for DRM with the LDH precursor. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The study synthesized a Ni/Al2O3 catalyst with hydrotalcite precursor, demonstrating superior catalytic activity and anti-coking ability. H2-TPD results showed that the NiAl-LDH precursor facilitated improved Ni dispersion and more Ni-Al2O3 interface, crucial for CH4 and CO2 activation. The importance of LDH structure was further confirmed by the decreased catalytic stability of catalysts with non-LDH phase or turbostratic structure.