The reactors used for Selective Catalytic Reduction (SCR) of NOx require low pressure
drop structured catalyst packing. Structured packings, such as ceramic foams, are gaining increasing
interest for application in low pressure drop reactors, membrane reactors and catalytic distillation
units. In this work, cobalt ion exchanged mordenite (Co-HMOR)-coated cordierite-based foams
produced by the replication method were evaluated for catalytic reduction of NOx with methane.
The addition of 0.3 wt.% Pd to 2 wt.% Co-HMOR leads to a material that can convert 50 % NOx to
N2 at 450 °C in a reaction mixture containing 2000 ppm CH4, 1000 ppm NOx, 5 % O2 and balance
helium, at GHSV=17000 h-1. Although in an early stage of development, an efficient coating
procedure was explored and different ways of exchange of Co and Pd cations into mordenite
(Si/Al=10) were studied. Additions of 2 wt.% fumed silica enhanced adhesion of the zeolite onto
the ceramic foam. Pd-exchanged Co-HMOR showed to be very sensitive to steam. A 50 % decrease
in NOx conversion to N2 was observed after Pd/Co-HMOR samples were exposed at 450 °C to a
reaction mixture containing 2 vol% H2O. Although further research is needed to ascertain the
mechanism of this deactivation behaviour, agglomeration of Pd forming PdO particles is envisaged.
Factors and Interactions that Influence the Pressure Drop Across An Air Volume Reducing Device on Low-Pressure Water Distribution Networks
