Effect of low loading of yttrium on Ni-based layered double hydroxides in CO2 reforming of CH4

Ni/Al/Mg layered double hydroxides (LDHs) modified with low loading of yttrium (0.2 and 0.4wt%) were used in dry reforming of methane at 700 degrees C. Physicochemical characterization, such as: X-ray fluorescence, N-2 sorption, X-ray diffraction, temperature programmed reduction in H-2, temperature programmed desorption of CO2, H-2 chemisorption, thermogravimetry analysis coupled by mass spectrometry and Raman spectroscopy, showed that the introduction of low loadings of yttrium lead to a smaller Ni degrees crystallite size, a decrease in reducibility of the nickel, and a decreased number of basic sites in the modified Ni/LDHs catalysts. The doping with 0.4wt% of Y improves catalytic activity resulting in higher CH4 and CO2 conversions at 700 degrees C, i.e., ca. 84% and ca. 87%, respectively with no clear deactivation observed after 5h run. The increase in CO2 conversion and a decrease of H-2/CO ratio indicates that side reactions occurs during DRM.