Methanation at Very Low COx/H2 Ratio: Effect of Ce on Ni–Ce–Al Catalyst Properties and Empirical Kinetics

• Published in: Catalysis letters 2019-01, Vol.149 (1), p.338-346
• Main Authors: Michalska, Kamila, Kowalik, Paweł, Próchniak, Wiesław, Borowiecki, Tadeusz
• Format: Article
• Language: English
• Subjects: Activation energy; Aluminum; Carbon oxides; Catalysis; Catalysts; Cerium; Cerium oxides; Chemistry; Chemistry and Materials Science; Empirical equations; Exponents; Industrial Chemistry/Chemical Engineering; Methanation; Nickel; Organometallic Chemistry; Oxides; Physical Chemistry; Precipitation (Meteorology); Properties (attributes); Rare earth metal compounds; Reaction kinetics
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-018-2607-x

The effect of CeO 2 on catalytic properties of Ni–Al CO x methanation catalyst obtained by co-precipitation and thermal processing of hydroxycarbonate precursors was discussed. A series of model Ni–Ce–Al catalysts with variable content of cerium oxide were synthetized and the effect of modifier on physicochemical properties and on methanation rate was studied with regard to the temperature and the concentration of carbon oxides. Values of activation energy and turn-over frequencies and exponents in empirical kinetic power rate equations were determined. The analysis of exponents values provided information about probable changes of carbon oxides sorption. A higher activity of Ni–Al–Ce catalysts in methanation reaction was found as compared to reference Ni–Al catalyst. Ce modified Ni–Al catalysts also showed higher TOF values which proves the formation of more active centers. Graphical Abstract