Ag-Al-MCM-41 catalysts used for toluene adsorption at low temperature

ASPROMONTE S., TISCORNIA I., MIRÓ E., BOIX, A.

Sorrento, Italia

Congreso; 16th International Zeolite Conference and 7th International Mesostructured Materials Symposium; 2010

Due to increasing regulations to control emissions of pollutants (nitrogen oxides [NOx], CO, hydrocarbons [HCs]) caused by fixed and mobile sources, the design of new technologies is essential for controlling emissions of unburned HCs in combustion processes and of NOx. In mobile sources, 80% of HCs emitted occurs between 60 and 90 seconds after starting the car engine [1]. Therefore, the purpose of this work is to trap HCs during the initial phase at low temperature and keep them up to normal operating temperature of the catalytic converter. Thus, the HC adsorbed on the solid can act as a reducing agent for NOx in real operating conditions. This alternative is a combined-effect solution which has not yet been explored in the open literature and which promotes the development of metal-zeolite catalysts [2]. The main disadvantage of the zeolites in adsorption processes is the fact that their limited pore size prevents the efficient processing of large molecules. Consequently, it is necessary to develop structured mesoporous catalysts able to combine the proposed alternative and solve the limitations on the pore size. This work presents the preparation of mesoporous MCM-41 and Al-MCM-41 catalysts with the addition of Ag, as well as the physicochemical characterization by techniques such as XRD, FTIR and SEM. It also presents a study of the behavior in the adsorption of toluene coupled to the selective catalytic reduction of NOx.