Mathematical and Experimental Study of Selective Catalytic Reduction of NO by NH3 over V2O5/SiO2 Catalyst in Fixed and Fluidized-bed Reactors

The selective catalytic reduction (SCR) of nitric oxide by ammonia in the presence of oxygen on silicasupported vanadium oxide catalyst was studied in fixed and fluidized-bed reactors, and two different mathematical models were proposed for these types of reactors. The solution of the proposed models would result in the NO concentration profile through the reactors for different operating conditions. To evaluate the accuracy of the proposed models, an experimental apparatus was erected, and the obtained experimental data were compared with the values predicted by the models. A good agreement was observed between these values. Once the validity of the proposed models was verified, they were used to study the effects of inlet gas temperature, O2 and NO concentrations in the feed gas, and gas hourly space velocity on the conversion of NO for engineering application. The results for the employed catalyst showed that high NO conversion was occurred at temperatures of 280-300 oC, GHSV less than 2000 h-1, and O2 concentration greater than 15% v/v for fixed-bed operation and 10% v/v for fluidizedbed operation. These results clearly demonstrate the high potential for this catalyst to be applied commercially for the control of NOx emissions from flue gases of different sources.

Keywords:

Selective Catalytic Reduction (SCR) , Nitric oxide , Mathematical model , Fixed-bed reactor , Fluidized-bed reactor , V2O5/SiO2 catalyst