The adsorption and catalytic properties of Cu-ETS and Cu-ZSM molecular sieves in NO_x removal by reduction

摘要

In this work, the activity of various copper catalysts with low and high copper contents was studied in the reaction of NO rection by ethene in oxidizing atmosphere (NO-C_2H_4-O_2). The catalysts were prepared by depositing various copper amounts in different host microporous systems : a titanium silicate (ETS-10) and an alumino-silicate (ZSM-5). The differences in the character of the copper sites were mainly determined by the adsorption properties of the catalysts towards NO, CO and C_2H_4 probes. The corresponding adsorption energies were determined by microcalorimetry. The results are discussed in terms of relations between activity and adsorption properties of the copper sites. The samples presenting the best NO adsorption properties are also the most active in the NO reduction.