La1−x(Ce, Sr)xNiO3 perovskite-type oxides as catalyst precursors to syngas production through tri-reforming of methane. (26th August 2022)

• Record Type: Journal Article
• Authors: Bertoldi, Juliana; de Campos Roseno, Karina Tamião; Schmal, Martin; Lage, Vitor Duarte; Lenzi, Giane Gonçalves; Brackmann, Rodrigo
• Is Part Of: International journal of hydrogen energy. Volume 47:Number 73(2022)
• Page Start: 31279
• Page End: 31294
• Publication Date: 2022-08-26
• Subjects: Perovskite-type oxides -- Tri-reforming of methane -- Syngas production -- Hydrogen; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.07.053
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: LaNiO3 (LN), La0.95 Ce0.05 NiO3 (LCN) and La0.95 Sr0.05 NiO3 (LSN) perovskites were synthesized by the polymeric precursor method to act as catalyst precursors for the Tri-reforming of methane (TRM). The majority phase determined for the LCN perovskite was LaNiO3, whereas, for LN and LSN, it was La2 NiO4 . It was not possible to determine segregated strontium phases for LSN, but LCN presented a small amount of CeO2 . All the catalysts presented similar methane conversions (around 75%), however differed in CO2 conversion. LCN was the sample with the highest CO2 conversion (32%), while the values recorded for the LN and LSN samples were 21.9 and 17.1%, respectively. The partial substitution of La 3+ by Ce 4+ leads to a higher CO2 conversion due to the redox properties of cerium, which promotes CO2 disproportion at the oxygen vacancies generated by cerium, providing more oxygen species that oxidize the coke at the surface. The most active sample for CO2 conversion (LCN) was also the least selective for hydrogen, generating a synthesis gas with an H2 /CO ratio of 1.2, while the less active LN and LSN samples were more selective for hydrogen (H2 /CO = 1.5–1.6). Thus, it is possible to generate synthesis gas suitable for different applications depending on the metal incorporated into the LaNiO3 perovskite. Graphical abstract: Image 1 Highlights: LaNiO3 is the majority phase detected for all the catalysts. LCN is the catalyst that most rapidly reaches steady state in TRM. LSN provides interactions between strontium phases and coke. CO2 conversions are higher for La0.95 Ce0.05 NiO3 than for the other catalysts. H2 /CO molar ratio follows the order: LN ≈ LSN > LCN.