RELIABILITY OF PULSE-CHROMATOGRAPHIC NITROUS-OXIDE TITRATIONS OF THE COPPER SURFACE-AREA ON CU-ZNO-MEOX CATALYSTS IN CONNECTION WITH THE CHARACTERIZATION OF THEIR THERMOSTABILITY

The reactive chemisorption of nitrous oxide on copper surfaces has been used to characterize the thermostability of CuO-ZnO-MeOx catalysts (Me: Mn, Cr, Al) for the hydrogenation of carbon monoxide to alcohol mixtures. An enhanced consumption of nitrous oxide has been observed on catalysts treated in hydrogen above 573 K. Additional nitrous oxide was consumed for the reoxidation of the partially reduced surface of the oxides. A method to avoid an over determination of copper surface areas is demonstrated.