Affiliation: | aInstitute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, “Acad. G. Bonchev” str., bl. 11, 1113 Sofia, Bulgaria bLaboratory of Industrial Chemistry, Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, 20500 Åbo/Turku, Finland |
Abstract: | Single and bi-metallic silver modified ZSM-5 catalysts were synthesized using different methods of preparation, characterized by several techniques and tested in simulated diesel conditions. Additionally the catalytic behaviour of the most active catalyst, containing 5 wt.% Ag and prepared by impregnation (5Ag(Imp)-H-ZSM-5), was studied over a broad temperature range with two reducing agents (octane and propene). To correlate the catalytic activity of the prepared catalysts with preparation parameters the materials were characterized by XRD, SEM, N2-physisorption, octane/propene-TPD, EPR and ICP techniques. A dual bed system consisting of Ag/alumina and the most active zeolitic material (5Ag(Imp)-H-ZSM-5) was shown not only to substantially enhance the activity of Ag/alumina in the low temperature region, but also to completely oxidize the CO and unburned hydrocarbons. |