Catalytic purification of car exhausts over cobalt- and copper-based metal oxides promoted with platinum and rhodium
Artikel i vetenskaplig tidskrift, 1995

25 Alumina-and silica-supported oxide-based catalysts were prepared, with the overall metal composition La(0.45)Sr(0.15)Ce(0.35)Zr(0.05)M(1.0) (M=Co or Cu) and promoted with 0-0.5 mg Pt-Rh per gram catalyst. The catalysts were evaluated with respect to light-off temperatures and redox characteristics, using NO/CO/C3H6/O2/N2 gas mixtures to simulate car exhaust. The activities for complete oxidation of propene and carbon monoxide increased with increasing content of metal oxides and noble metals. The catalysts were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) combined with energy-dispersive spectroscopy (EDS) analysis, temperature-programmed reduction (TPR), and specific surface area measurements (BET). SEM/TEM/XRD revealed that the alumina-supported catalysts contained well dispersed oxides of the added elements, whereas the silica-supported catalysts contained significantly larger particles of the copper or cobalt oxides, The TPR peak for reduction of cobalt oxide shifted toward lower temperatures with increasing content of Pt-Rh, indicating hydrogen spill-over from the noble metals to the cobalt oxide. The catalytic activity of the Co-based oxides supported on alumina and promoted with 0.49 mg Pt-Rh per gram catalysts was comparable to the activity of a commercial three-way catalyst (TWC), containing more than 4 times as much Pt-Rh.

CARBON MONOXIDE OXIDATION

COBALT

RHODIUM

COPPER

EXHAUST GAS CATALYSIS

PLATINUM

PROPENE OXIDATION

Författare

Pei-yan Lin

Magnus Skoglundh

Institutionen för teknisk kemi

Lars Löwendahl

Institutionen för teknisk kemi

Jan-Erik Otterstedt

Institutionen för teknisk kemi

Leif Dahl

Kjell Jansson

Mats Nygren

Applied Catalysis B: Environmental

0926-3373 (ISSN) 1873-3883 (eISSN)

Vol. 6 237-319

Drivkrafter

Hållbar utveckling

Styrkeområden

Nanovetenskap och nanoteknik

Transport

Energi

Materialvetenskap

Ämneskategorier

Kemiteknik

DOI

10.1016/0926-3373(95)00008-9