Dry reforming of methane over La2O2CO3-modified Ni/Al2O3 catalysts with moderate metal support interaction

Abstract

The modulation of the interaction between the active metal and the underlying support material plays a key role and remains a challenge in many important catalytic reactions. This paper describes a new method for the modification of Ni/Al2O3 by La2O2CO3, which is responsible for modulating the interaction between Ni and the Al2O3 support. When La2O2CO3 is loaded on the Al2O3 support as a La2O3 precursor, combined with XRD, H2-TPR, H2-pluse chemisorption, Raman spectroscopy and TEM characterization, it is found that La2O2CO3 can prevent Ni from entering the alumina support and forming NiAl2O4. This strategy allows more Ni to be reduced and exposed as active sites. Consequently, the La2O2CO3 modified Ni/Al2O3 exhibited superior activity with respect to the reference La2O3 modified Ni/Al2O3 and original Ni/Al2O3 in dry reforming of methane (DRM). At the same time, La can cover the acidic sites of alumina and increase the alkalinity of the catalyst, thereby promoting carbon dioxide adsorption and activation, and inhibiting carbon deposition. In addition, the introduction of La also inhibits the sintering of Ni under harsh reaction conditions by enhancing the interaction between Ni metal and the support. This modification method can simultaneously improve the reactivity and stability of the catalyst by altering the interaction between the metal and the support.