Honey-comb catalysts

Fig. 8 Honey comb catalyst in front of module. (View this art in color at www.dekker.com.)...

HIE) Hlavacek, V., Rathousky, J. Oscillatory Behavior of Metallic Honey Comb Catalysts,... 

The ceramic catalyst is a homogeneous mixture of all components. After mixing with binders, plastifiers, and glass fiber the mass is extruded to honey-comb-structured elements, which are dried and calcined (Fig. 10.1). 

FIGURE 10.1. DENOX catalyst The catalyst elements exhibit a honey-comb-like structure (upper photo) view into a reactor partly filled with catalyst modules (lower photo). By courtesy of Porzellanfabrik Frauenthal GmbH and Austrian Energy and Environment SGP Wagner-Biro GmbH, Austria. 

Fig. 6 shows the cross-sectional SEM micrograph of the film catalysts which were prepared at different condition. PMo-PSF-DMF(56V) was prepared by casting the solution at 56 % RH and by drying it in vacuum. PMo-PSF-DMF(85) was prepared by casting and drying the solution at 85 % RH. PMo-PSF-DMF(56V) had no micropores because all water vapor and DMF were evacuated as shown in Fig. 6. PMo-PSF-DMF(56V) was a non-porous film and it showed no measurable microporous properties. On the other hand, PMo-PSF-DMF(85) had well-developed micropores and honey comb type cells with an average pore diameter of 0.25 pm.

Its total pore area was about 25 m2/g. The blending of PMo with PSF is a physical one and PMo-PSF-DMF film can be regarded as a finely distributed PMo catalyst supported on PSF as described in Section 3.1. Most of PMo in the PMo-PSF-DMF(85) film catalyst Is presumed to exist on/near the surface of pore wall as an encapsulated and physisorbed state after the phase separation process. It is proposed that each of micropore and honey comb type cell acts as a micro-reactor having well distributed PMo on/near the wall. 

Commercial catalyst Honey comb structure made by Degussa AG., West Germany, and obtained from Volvo AB, Gothenburg, Sweden. 

Catalyst honey comb substrate permeated with precious metals... 

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