ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Study of the Catalytic Activity of Calcined Ni/Mg/Al (Mn) Hydrotalcites for N₂O Decomposition

L. Obalová, M. Valášková, F. Kovanda, Z. Lacný, and K. Kolinová

Department of Physical Chemistry and Theory of Technological Processes, Technical University of Ostrava, CZ-708 33 Ostrava

E-mail: lucie.obalova@vsb.cz

Received: 1 April 2003

Abstract: Mixed oxide-based catalysts prepared by thermal decomposition of Ni-(Mg)-M(III) hydrotalcite-like compounds (M(III) = Al, Mn) were used in catalytic decomposition of nitrous oxide in order to describe the catalytic activity of multicomponent catalysts and to study the effect of Mg²⁺ presence in the catalysts structure. Although the catalytic activity of prepared Ni-Al and Mg-Mn calcined hydrotalcites was high, the simultaneous presence of both transition metal cations Ni²⁺ and Mn³⁺ in the catalyst structure caused a decrease of N₂O conversion and specific surface area. The N₂O conversions decrease with increasing content of Mg in the Ni-Al system and increase in the Ni-Mn system. The rise of Mg content in the catalysts resulted in larger surface area and higher thermal stability of both Ni-(Mg)-Al and Ni-(Mg)-Mn samples. The prepared hydrotalcites as well as calcined products were characterized by the thermal analysis (TG/DTA), powder X-ray diraction (XRD), and BET surface area measurements.

Full paper in Portable Document Format: 581a33.pdf

Chemical Papers 58 (1) 33–40 (2004)