Hydrogen production from steam and oxidative steam reforming of liquefied petroleum gas over cerium and strontium doped LaNiO3 catalysts

This study investigated LaNiO3 doped with small amounts of cerium and strontium as catalyst precursors for LPG steam and oxidative reforming. La1-xCexNiO3 (x=0, 0.05, 0.1) and La1-xSrxNiO3 (x=0, 0.05, 0.1) perovskite-type oxides were prepared by precipitation. The characterization showed that samples doped with cerium had smaller nickel average particle size and higher oxygen storage capacities when compared to the samples containing strontium. All the samples were tested for LPG steam and oxidative steam reforming at 873 K. The LPG steam reforming results showed that all catalysts presented strong deactivation. The addition of a small amount of oxygen to the system (oxidative steam reform) leads to better catalytic performance for all samples. The La0.95Ce0.05NiO3 precursor stood out by presenting better performance for hydrogen production in all conditions. These results can be attributed to the presence of ceria and to smaller metallic nickel average crystallite sizes. The results of the in-situ X-ray diffraction analysis indicated that for the sample originated from La0.95Ce0.05NiO3, the reduced form of the material was preserved longer, thus justifying leading to greater stability in reaction conditions. In-situ XANES data collected during steam LPG reforming showed that the samples derived from La0.95Ce0.05NiO3 presented no significant change in the increase of the white line, which, in this case, would characterize the oxidation of the precursors. The same reforming reactions were conducted at higher temperatures using La0.95Ce0.05NiO3 precursor, and the results showed that at higher temperatures it is possible to maintain high activity, with stable hydrogen production. (C) 2016 Elsevier B.V. All rights reserved.