Catalyst Impregnation in Fluidized Beds

The process is affected by various apparatus and process variables, such as nozzle configuration, gas inlet temperature, and flow rate, as well as material properties such as contact angle and surface tension, liquid viscosity and the texture of the solid particles. However, as the mentioned authors state, the solute distribution in the porous particles is mainly controlled by the following two time constants  

Desportes et al. (2005) conducted experiments with coarse alumina particles (mean diameter 2.4 mm) to show that the homogeneity of solute distribution in the particles depends on the ratio between the two characteristic times tdry/twet- Two different experimental conditions that correspond to fast drying and to slow drying (low and high values of tdry/twet. respectively) were realized, as displayed in Tab. 7.4. Manganese nitrate was the precursor material. Material samples were removed after 

Process parameter Unit Fast drying Slow drying 

Additional measurements by Desportes et al. (2005) indicate that the pore size distribution pattern of the initial support is conserved during increasing catalyst penetration (transition from SI to S4 in Fig. 7.34). However, pore sizes are reduced, so that the specific surface area and the specific pore volume of the material gradually decrease (Tab. 7.5). 

It should be noted that the quality of the products discussed in this section is mainly defined by catalytic activity and catalyst pellet efficiency, the latter being a measure of mass transport limitations within the particle. Depending on the 

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