Dechlorination of polychlorinated phenols on bimetallic Pd/Fe catalyst in a magnetically stabilized fluidized bed
نویسندگان
چکیده
Dechlorination of 2,4,6-trichlorophenol was performed within a magnetically stabilized fluidized bed (MSFB), containing a palladized iron (Pd/Fe) catalyst entrapped within alginate beads. Kinetic parameters of this multistep reaction yielding phenol as a final product were preliminarily defined in a batch system using four different intermediates as substrates for Pd/Fe catalyzed dechlorination. Further work using the fluidized bed reactor provided the basis for mathematical description of the full dechlorination process both with and without the assistance of an applied magnetic field. The resulting model includes convective mass transfer in the bulk media, diffusion within the alginate beads and reaction kinetics, including catalyst deactivation caused by passivation. Very good agreement was observed between experimental data and predictions of the model. These results confirmed the benefit of using MSFB reactors for more efficient dechlorination of toxic polychlorinated phenols, as compared to fluidized bed reactors without magnetic field stabilization.
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